This is part five of a five-part series:
1) Understanding Micronutrient and Essential Nutrient Categories
2) Understanding Nutrient Targets
3) Considerations for Micronutrient Tracking: Precision and Difficulty
4) Which Micronutrients Are Worth Monitoring?
5) Micronutrients are Important, But They Aren’t Everything

Our Knowledge Base also has an archive of additional information about each nutrient you can track in MacroFactor, including what the nutrient actually does, the likelihood of insufficient or excessive intake, and good food sources for each nutrient.

With that out of the way, let’s dive in!

Beware of Micronutrient Reductionism

To wrap up this series, I think it’s worth cautioning against something I like to refer to as micronutrient reductionism.

Humans have a tendency to like numerical targets that they can treat as proxies for outcomes that matter to them. In this case, I think there’s a tendency to operationally define a “healthy diet” as “a diet that contains the recommended amounts of all essential nutrients.”

In a vacuum, there’s nothing wrong with that. If you try to eat a variety of minimally processed foods that allow you to meet all of your nutrient targets, I think you’d have a hard time not eating a generally healthy diet.

However, it can become problematic when the targets themselves become your only goal and metric for success. In other words, you might run into problems when a proxy for your goal (in this case, meeting your micronutrient targets) replaces the actual goal itself (eating a diet that generally promotes good health).

When the focus shifts excessively toward numerical targets, you might start making choices that are optimized for the pursuit of those targets instead of the pursuit of the actual goal. Just as one example, consuming preformed vitamin A (retinol) is a more efficient way to meet your vitamin A targets than consuming carotenoids that can be converted to vitamin A. So, you might “realize” that you’re better off consuming one serving of liver per week, instead of consuming a variety of fruits and vegetables that are rich in carotenoids. But, the effects of foods aren’t reducible to their macro- and micronutrient composition, so by going this route, you’d be missing out on a host of other benefits that come from fruits and vegetables.

Or, for a more extreme example, you might realize that there’s an incredibly simple “hack” for meeting your micronutrient targets – just take a multivitamin. Then, with your micronutrient needs taken care of, your diet is already de facto “healthy,” so your other food choices are effectively irrelevant. 

However, micronutrients aren’t everything. Adequate micronutrient intake is necessary for maximizing the general healthiness of a diet, but it’s not sufficient. In other words, adequate micronutrient intake helps you avoid certain disease states that can result from micronutrient deficiencies, but if you “just” meet your micronutrient targets, you’re not capturing all of the benefits that can come from a healthy diet.

There are plenty of health-promoting bioactive compounds (mostly in fruits and vegetables) that aren’t classified as essential nutrients. Not consuming these compounds doesn’t cause any known diseases, but these compounds do still bring unique benefits.

Two examples are polyphenols and isothiocyanates.

Polyphenols are found in a variety of fruits and vegetables – most notably berries, cherries, pomegranate seeds, and certain spices (like turmeric). Polyphenols have positive effects on neurodegenerative disease risk, inflammation, cancer risk, cardiovascular health, type II diabetes risk and management, and obesity risk via a surprisingly wide array of mechanisms.

If you were simply optimizing for micronutrient intake, you might reasonably eschew most of the foods that are high in polyphenols, because most of them aren’t micronutrient powerhouses. For example, blueberries have exceptionally high concentrations of a class of polyphenols called anthocyanins, but blueberries aren’t particularly rich in most vitamins or minerals. They’re a decent source of vitamin K and manganese (though there are plenty of foods with much higher concentrations of both nutrients), and they’re an alright source of vitamin C (though they pale in comparison to citrus fruits), but that’s about it. The micronutrient profile of cherries gives you even less to be excited about.

Isothiocyanates are a class of compounds primarily found in cruciferous vegetables (broccoli, brussels sprouts, cabbage, mustard greens, kale, etc.). They have potent antioxidant, anti-inflammatory, anticancer, and antibacterial effects. Much like polyphenols, they exert these effects via a surprisingly wide array of mechanisms.

In terms of micronutrients, cruciferous vegetables fare a bit better than polyphenol-rich fruits, but you still probably wouldn’t pick them out of a lineup. They’re pretty good sources of vitamins C and K, but they probably wouldn’t be your first choice if you were optimizing your food choices exclusively for micronutrient content.

The fact of the matter is that you can’t reduce the overall “healthiness” of a diet to its micronutrient content. If you could, the humble multivitamin would be a wonder drug, but it’s not. The same applies to supplementation of individual vitamins that tend to be under-consumed (like vitamins A and D).

So, if you track your micronutrient intake, just make sure you don’t miss the forest for the trees. Micronutrient intake is important, but don’t let the pursuit of micronutrient targets come at the expense of (or take the place of) consuming a generally healthy diet. Eat your protein, eat your fiber, don’t go overboard with added oils and sugars, and make sure you’re consuming a variety of fruits and vegetables. A healthy diet will generally be a micronutrient-rich diet, but don’t assume that micronutrient completeness will necessarily guarantee that your diet is optimized for health. It might just be optimized for micronutrient completeness. 

The post Micronutrients Are Important, But They Aren’t Everything appeared first on MacroFactor.

This is part four of a five-part series:
1) Understanding Micronutrient and Essential Nutrient Categories
2) Understanding Nutrient Targets
3) Considerations for Micronutrient Tracking: Precision and Difficulty
4) Which Micronutrients Are Worth Monitoring?
5) Micronutrients are Important, But They Aren’t Everything

Our Knowledge Base also has an archive of additional information about each nutrient you can track in MacroFactor, including what the nutrient actually does, the likelihood of insufficient or excessive intake, and good food sources for each nutrient.

With that out of the way, let’s dive in!

Which micronutrients should you monitor?

All micronutrients are important for human health and development, but not all micronutrients are equally worth monitoring. In developed countries, micronutrient deficiencies are very uncommon. Micronutrient intake scales with total energy intake, so micronutrient deficiencies are more common in parts of the world with greater food scarcity. Similarly, insufficient micronutrient intake is less likely when you have access to a greater variety of foods. In parts of the world where a single crop accounts for a disproportionate fraction of total energy intake (for example, parts of southeast Asia where rice accounts for the vast majority of total food consumption), micronutrient insufficiency is more common. Furthermore, targeted food fortification programs have done a lot to reduce rates of insufficient intake for key micronutrients that may be challenging to consume in adequate quantities from a normal varied diet.

However, some micronutrients are still regularly consumed in insufficient quantities, even in developed countries. So, if you track your micronutrient intake, it’s probably worth paying closer attention to the nutrients that many people struggle to consume in adequate quantities.

In the US, more than 25% of adults consume insufficient amounts (less than the EAR) of vitamins A, C, D, E, and K, along with calcium, magnesium, and potassium, and more than 10% of adults consume insufficient amounts of folate, vitamin B6, and zinc. In Europe, vitamin C, vitamin D, folate, calcium, selenium, and iodine are consumed in insufficient quantities by at least 20% of adults. 

Similarly, insufficient omega-3 EPA and DHA intake is pretty common. The recommended combined intake of EPA and DHA is 250mg/day, but adults in the US only consume about 90mg/day, on average. Fiber intake is a similar story: Americans average 10-15g of fiber per day, while the recommended intake is 25g for women and 38g for men. Choline intake is also below the recommended levels; the USDA recommends 425mg/day for women 550mg/day for men, while the average intakes are about 275mg/day for women and 400mg/day for men.

On the flip side, many people in developed countries consume more sugar and saturated fat than nutrition researchers and health officials recommend.

The table below roughly summarizes how much attention is warranted for each nutrient you can track in MacroFactor (not just micronutrients). Of note, it’s summarizing the relative likelihood of insufficient or excessive intake – not the magnitude of the risk posed by insufficient or excessive intake of each nutrient.

Keep in mind, the table above roughly summarizes population-level rates of insufficient or excessive intake for each nutrient. The probability that you’ll have insufficient or excessive intake of any particular nutrient depends on a variety of factors. If you have a varied diet largely composed of minimally processed nutrient-dense foods, the likelihood that you’ll have insufficient intake for most nutrients will be lower. Conversely, if you consume a less varied diet (i.e. if you’re a bodybuilder who just consumes chicken, rice, and broccoli, or if you only eat chicken nuggets), the likelihood of insufficient or excessive intake of certain nutrients will increase. The same applies if you consume more “empty calories” from added oils or sugars. Similarly, the likelihood of insufficient micronutrient intake is higher when you’re in a very large energy deficit than when you’re at energetic maintenance or in an energy surplus, simply due to the amount of food you’re consuming. Certain health conditions can affect your micronutrient needs as well.

In short, take the table above in its proper context – it’s meant to provide a starting point for most people, but the list of micronutrients you might benefit from monitoring may be different. It might be a longer list, a shorter list, or a different list altogether, depending on your lifestyle, dietary patterns, life circumstances, and potential disease states.

Of note, insufficient intake shouldn’t be confused with deficient intake. The effects of insufficient intake may be small or even imperceptible on an individual level, while still being associated with slightly worse population-level effects. For instance, insufficient calcium intake is associated with about a 10% increase in osteoporosis risk, but a 10% increase in risk is far from a guarantee that you’ll develop osteoporosis. Full-on calcium deficiency, on the other hand, can cause muscle spasms, kidney damage, severe neurological symptoms, seizures, and congestive heart failure.

If you’re concerned that you might be deficient in a particular micronutrient, or that you might be suffering ill effects from insufficient or excessive intake of a particular nutrient, you should discuss those concerns with a medical doctor or a registered dietician.

The post Which Micronutrients Are Worth Monitoring? appeared first on MacroFactor.

This is part three of a five-part series:
1) Understanding Micronutrient and Essential Nutrient Categories
2) Understanding Nutrient Targets
3) Considerations for Micronutrient Tracking: Precision and Difficulty
4) Which Micronutrients Are Worth Monitoring?
5) Micronutrients are Important, But They Aren’t Everything

Our Knowledge Base also has an archive of additional information about each nutrient you can track in MacroFactor, including what the nutrient actually does, the likelihood of insufficient or excessive intake, and good food sources for each nutrient.

With that out of the way, let’s dive in!

The (im)precision of micronutrient tracking

If you want to track your micronutrient intake, you should be aware that estimates of micronutrient intake based on food tracking data are far more imprecise than estimates of macronutrient or energy intake based on food tracking data.

By law, the calories and macronutrients listed on a food label (typically) must be within 20% of the actual values. That’s a feasible regulation to enforce, and food-level errors of that magnitude produce considerably smaller errors in daily, weekly, and monthly calorie and macronutrient counts.

Micronutrient labeling and reporting, on the other hand, is typically based on the micronutrient content of standard reference foods. It’s simply not feasible to expect food manufacturers to do a full vitamin and mineral assay on all of the foods they produce. So, if a food contains 60g of spinach per serving, and a standard reference database says that spinach has 16.8mg of vitamin C per 60g, the food is assumed to have 16.8mg of vitamin C per serving.

However, actual micronutrient content can vary considerably within a single food product.

For example, a 2018 study testing different batches of baby spinach at different times of the year found that baby spinach contained anywhere from 5.6-39.6mg of vitamin C per 60g serving. And, unlike calorie and macronutrient content, errors in label claims may not wash out over relatively short time scales, because vitamin C content significantly varied by season. In the winter, spinach averaged 26.16mg of vitamin C per 60g serving; in the summer, it averaged just 10.74mg of vitamin C per 60g serving. So, for multiple months at a time, your actual intake of vitamin C from spinach would be 35-40% lower than you thought it was (based on your food tracking data), and for multiple months at a time, your actual intake would be ~135% higher than you thought it was.

Now, I’ll readily admit that I cherry-picked a particularly extreme example to illustrate my point. Most foods don’t have micronutrient contents that vary to that large of an extent, and not all foods have micronutrient concentrations that exhibit significant seasonal variability. But, micronutrient tracking is inherently a bit fuzzier than calorie and macronutrient tracking. Calorie and macronutrient content may differ from label claims by up to 20%, but micronutrient content can easily differ from label claims by 50% or more, due to seasonal differences, regional differences (for instance, despite being next-door neighbors, scientists tend to report higher vitamin A and vitamin C levels in German produce than in Dutch produce), and variations in soil health and farming practices. 

Much like calorie and macronutrient tracking, daily errors in micronutrient tracking should be smaller than the errors present in individual foods. Calorie counts for individual products may be off by up to 20%, but your daily tracking error should generally be smaller than 10%. The same principle should apply to micronutrient tracking: the errors for individual foods can be very large, but the error for a full day (or full week, or full month) of tracking should generally be smaller. Unfortunately, we can’t model out the size of expected daily or weekly errors because there’s not a comprehensive reference documenting the difference between labeled and actual micronutrient contents for a representative set of food products. But, given the data presented here, I think you can reasonably expect your actual daily micronutrient intake to differ from your logged micronutrient intake by up to ~25%.

So, if you log 1000mg of calcium intake, it’s very unlikely that you actually consumed exactly 1000mg, but there’s a pretty decent chance that you actually consumed somewhere between 750 and 1250mg of calcium.

However, there’s another major complication when it comes to tracking micronutrients: most branded food items don’t report the content of most micronutrients.

How to track micronutrients

If you want to track your micronutrient intake, you should make a point of primarily logging “common foods” in MacroFactor.

Government agencies don’t require food manufacturers to list all of the nutrients contained in a food, and for good reason. The point of nutrition labels is to inform consumers about the content of nutrients that are most likely to impact consumers’ health. If every nutrient was listed on every nutrition label, the sheer size of the list would divert attention away from higher-impact nutrients.

So, in most countries, food manufacturers are required to report energy content, macronutrient content, sugar content, saturated fat content, fiber content, salt (or sodium) content, and the content of micronutrients added specifically for the purpose of food fortification (i.e. iron in many wheat-based products, or iodine in table salt). Beyond that, some countries require food manufacturers to report the content of a small handful of additional vitamins and minerals. For instance, the USDA requires US food manufacturers to report iron, calcium, vitamin D, and potassium content.

All other nutrient labeling is voluntary, and most food manufacturers don’t go beyond the bare minimum requirements.

For instance, a recent study reported on the frequency at which most nutrients were reported on food labels in the UK. See if you can guess which nutrients are required to be listed on UK nutrition labels, and which nutrients are only reported on a voluntary basis.

To give a real-world example, here’s a photo of a nutrition label for a can of chickpeas from my pantry:

The nutrients listed on the nutrition label are the nutrients mandated by the US government, and nothing more.

Conversely, here’s a link to the same product in the USDA food database, which reports full micronutrient content for thousands of foods. It shows that chickpeas also have non-zero amounts of magnesium, phosphorus, zinc, copper, manganese, selenium, vitamin A, all B vitamins except for B-12, vitamin C, vitamin E, vitamin K, and choline.

So, if I wanted to closely track my micronutrient intake, logging a serving of chickpeas by scanning the nutrition label of this product would result in undercounting of most micronutrients. Instead, I’d need to:

1. Calculate the energy content of my serving of chickpeas
2. Select the “common foods” entry for chickpeas
3. Adjust the serving size of the “common foods” chickpea entry to match the energy content of my serving of chickpeas
4. Log the “common foods” serving of chickpeas

The “common foods” in MacroFactor come from research-grade databases (like the USDA database and the NCCDB) with robust micronutrient reporting. So, if you want to track your micronutrient intake, you’ll need to make a point of logging common foods, instead of branded foods. If you primarily log branded foods, you’ll underestimate your intake of most micronutrients.

When you search for foods in MacroFactor, history items (items you’ve logged previously) will show up at the top of your search results, followed by custom foods you’ve created, followed by common foods, with branded foods at the bottom.

To help with common food logging, make sure to expand the list of common food results by tapping the “+15” arrow beside the “common” label. By default, your search results will show you the 5 common foods that best match your search query (based on a combination of text matching, and the frequency with which each food is logged). However, the specific item you’d like to log may not show up in the top 5 results; expanding the list to 20 foods by tapping the “+15” arrow will increase the probability of finding the common food you’d like to log. You can see an example in the video below:

For more complex foods, you might need to log individual common food ingredients that roughly match the energy and macronutrient content of the food you’d like to log. For instance, if you’re trying to log a branded egg and cheese sandwich in a way that will allow for full micronutrient reporting, you might need to log common food entries for bread, eggs, and cheese in amounts that roughly match the energy and macronutrient content of the particular branded sandwich you’re consuming.

Conversely, if you do want to primarily log branded foods due to convenience, or because you don’t care too much about closely monitoring your micronutrient intake, don’t stress out if it looks like you’re under-consuming most micronutrients. You’re probably not. You’re just logging foods that don’t have robust micronutrient reporting.

Since exclusively logging common foods is considerably more time-consuming and less convenient than tracking branded food items, you might want to consider spot-checking your micronutrient intake from time to time. For a week, make a point of exclusively (or almost exclusively) logging common foods, while consuming your normal diet. That will capture most of the upside associated with micronutrient tracking (letting you see which nutrients you might be under- or over-consuming) while minimizing most of the downside (the ongoing time cost of logging common foods instead of branded foods). As with most things in life, micronutrient tracking doesn’t need to be approached with an all-or-nothing attitude.

Of course, if monitoring your micronutrient intake matters deeply to you, and you don’t mind primarily logging common food items, there’s certainly nothing wrong with continuing to track mostly common foods so that you can monitor your micronutrient intake on an ongoing basis.

Rebecca laid out four general archetypes of micronutrient loggers in our announcement of the new micronutrient features in MacroFactor. Most people will generally conform to one of these four archetypes most of the time:

1. The Scale Shifter. This group will make no changes to their logging style because logging anything at all, even exclusively Quick Adds, is enough to take advantage of MacroFactor’s diet coaching systems, and to reach their exclusively body composition-related goals.
2. The Generalist. This group will have some additional health-related goals that involve common nutrients that are often found on nutrition labels, such as: fiber, saturated fat, sugar, or sodium. This group would be best served to avoid Quick Adds where possible, and spot check commonly consumed branded products every once in a while.
3. The Optimizer. This group will have an interest in “optimizing” their diet for micronutrient density, and will want to reference their nutrition intake versus almost every micronutrient range we have. When possible, this group will need to rely exclusively on common foods and break down multi-ingredient branded products into their common food constituent parts.
4. The Auditor. This group will oscillate between periods of rigorous micronutrient tracking to impact changes on their nutrition and periods of relaxed logging with emphasis on reaching their caloric targets. This group will be best served with using common foods exclusively during their nutrition audits and defaulting to using a combination of common foods, Quick Adds, and branded products during the majority of their app use.

Of note, it’s totally fine to be a Scale Shifter, Generalist, or Auditor. Most people don’t need to closely monitor all of their micronutrients, all of the time. But, if you do want to closely monitor your micronutrient intake, try to make a point of almost exclusively logging “common foods.”

The table below summarizes the mandatory nutrient reporting requirements in the US, Canada, Australia, and the EU. It will serve as a handy reference for which nutrients you can easily track by scanning barcodes and searching for branded foods, and which nutrients will require you to primarily log “common foods” if you’d like to monitor your intake. If a nutrient is only reported on a voluntary basis where you live, you’ll probably need to mostly log “common foods” if you’d like to accurately track your intake of that nutrient.

The post Considerations for Micronutrient Tracking: Precision and Difficulty appeared first on MacroFactor.

This is part two of a five-part series:
1) Understanding Micronutrient and Essential Nutrient Categories
2) Understanding Nutrient Targets
3) Considerations for Micronutrient Tracking: Precision and Difficulty
4) Which Micronutrients Are Worth Monitoring?
5) Micronutrients are Important, But They Aren’t Everything

Our Knowledge Base also has an archive of additional information about each nutrient you can track in MacroFactor, including what the nutrient actually does, the likelihood of insufficient or excessive intake, and good food sources for each nutrient.

With that out of the way, let’s dive in!

What do all of the Micronutrient Targets Actually Mean?

When you start reading about micronutrients, you’ll encounter a number of acronyms associated with nutrient targets: DRI, DRV, RDA, EAR, AR, PRI, UL, and AI. So, let’s briefly discuss what these acronyms mean, and where micronutrient targets come from.

DRI: Dietary Reference Intake

DRIs refer to all scientifically derived reference values for various nutrients. In other words, “DRI” is the general term to describe all of the other nutrient targets discussed below.

DRV: Dietary Reference Value

DRVs are identical to DRIs. In a trend that will continue below, American health agencies (primarily the United States Department of Agriculture – USDA) and European health agencies (primarily the European Food Safety Authority – EFSA) follow the same basic processes when creating nutrient targets, but they use slightly different terminology.

RDA: Recommended Dietary Allowance

Almost everyone (in the US, at least) has at least a passing familiarity with RDAs. Standard food labels present micronutrients in reference to their RDAs.

You can think of an RDA as a “better safe than sorry” micronutrient target. RDAs are designed to meet the needs of 97-98% of the population. In other words, most people can get away with consuming a bit less than the RDA for each nutrient, and very few people will need to consume more than the RDA.

PRI: Population Reference Intake

PRIs are the European version of RDAs. Much like DRIs and DRVs, RDAs and PRIs are identical concepts, communicating the same information.

EAR: Estimated Average Requirement

EARs are pretty self-explanatory. The EAR is the … estimated average requirement for a particular nutrient. For each nutrient, about half of individuals need to consume a bit more than the EAR for optimal health, and about half of individuals can get away with consuming a bit less than the EAR (assuming that intake needs for each nutrient are normally distributed).

For what it’s worth, I suspect a lot of people think about RDAs or PRIs in the manner they should think about EARs. In other words, I think a lot of people believe that RDAs are the average requirement for each nutrient, but you should really aim to exceed the RDAs. In actuality, EARs are the average requirement. So, if you want to make sure you’re covering your bases, you might want to ensure you exceed the EAR for micronutrients (in case your micronutrient requirements are a bit higher than average), but reaching the RDA or PRI means you’re probably comfortably in the clear.

AR: Average Requirement

ARs communicate the same information as EARs. Once again, this is just a difference in terminology between the US and Europe. EAR is the USDA’s term, and AR is the EFSA’s term.

AI: Adequate Intake

Americans and Europeans finally agree on an acronym!

AIs are similar to RDAs, PRIs, EARs, and ARs, but they’re a bit less scientifically rigorous. Basically, if you see an RDA, PRI, EAR, or AR, that means that there’s enough research to confidently determine population-level intake requirements for a particular nutrient. If you see an AI, that means that health agencies are confident that the nutrient is necessary for optimal health, but there’s not sufficient research to confidently determine population-level intake requirements for that particular nutrient.

So, to determine an AI, researchers will study the dietary patterns of people who are apparently healthy, and who aren’t experiencing the negative effects that should result from inadequate intake of a particular nutrient.

From there, an AI may be determined in a variety of different ways. Generally, the AI is the average intake of the nutrient in an apparently healthy population. However, AIs are sometimes based on the lowest observed intake at which no signs of insufficiency are observed in a population. Other times, they’re defined against some external standard; for instance, the AI for calcium intake in infants is based on the typical calcium intake infants would achieve if they were exclusively breastfed.

In other words, the exact information being communicated by an AI varies from nutrient to nutrient, but the functional takeaway is the same: if you reach the AI for a particular nutrient, there’s a very good chance that you’re consuming enough of that particular nutrient.

UL: Tolerable Upper Intake Level

Often, there are no known drawbacks of consuming “too much” of a particular nutrient. For some nutrients, however, excessive intake can cause problems that range from mild to severe.

For example, excess vitamin C intake generally just causes a bit of nausea and diarrhea, whereas grossly excessive vitamin A intake can be lethal.

ULs communicate “the maximum daily intake levels at which no risk of adverse health effects is expected for almost all individuals in the general population – including sensitive individuals – when the nutrient is consumed over long periods of time.” (source)

In other words, ULs are quite conservative. They’re determined based on:

1. The highest continuous intake at which no adverse effects are observed (no observed adverse effect level – NOAEL) or the lowest continuous intake at which rare adverse effects start to be observed (lowest observed adverse effect level – LOAEL)
2. The severity of the consequences of an excessive intake. ULs are more conservative when the result of excessive intake is more severe (death or long-term damage), and less conservative when the result of excessive intake is less severe (a bit of diarrhea, for instance).
3. The amount, type, and strength of the evidence used to determine the NOAEL or LOAEL. ULs will be more conservative when the NOAEL or LOAEL is extrapolated from animal research or based on a small handful of case studies, and less conservative when there’s a lot of high-quality human data to confidently establish a firm NOAEL or LOAEL.

So, you’ll probably be fine if you exceed the UL for a particular nutrient from time to time, but you probably shouldn’t make a habit of it.

Just to illustrate, 100g of raw beef liver contains about 5000mcg of vitamin A, and the UL is just 3000mcg/day. However, acute toxicity generally requires a single dose in excess of 100-times the RDA. The RDA is 900mcg for men and 700mcg for women, so an acute toxic dose is typically at least 70,000-90,000mcg of vitamin A. Furthermore, chronic toxicity generally doesn’t occur unless people consume at least 10-times the RDA (7000-9000mcg/day) consistently for a period of months-to-years (source).

So, a single serving of liver will probably put you above the UL for vitamin A, but that doesn’t mean that eating a single serving of liver will cause problems for most people. Furthermore, if you’re not at elevated risk for hypervitaminosis A, a daily serving of liver will probably never cause any problems. However, if you are at elevated risk for hypervitaminosis A, and you ate 100g of liver every day, that might cause problems over a period of months-to-years.

Basically, you probably don’t need to call poison control if you slightly exceed the UL for certain micronutrients from time to time. But, if you’re regularly exceeding the UL for a particular micronutrient, it would probably be a good idea to modify your diet so that your normal consumption of the particular nutrient falls below the UL.

LTI: Lower Threshold Intake

LTIs are essentially the inverse of RDAs. Assuming the intake needs for most nutrients are normally distributed, the EAR is right in the middle of the distribution, and RDA is two standard deviations above the mean, and the LTI is two standard deviations below the mean. So, about 95% of individuals will have intake requirements between the LTI and the RDA. If you’re meeting or exceeding the RDA of a particular nutrient, there’s a very small chance that your intake is insufficient. Conversely, if you’re barely meeting or falling short of the LTI, there’s a very small chance that your intake is sufficient – only 2-3% of individuals will have nutrient needs below the LTI.

Just as a general note before moving on, I’ll mostly be sticking with the American acronyms (RDA, EAR, and DRI) for the rest of this article and this series – using both sets just got unnecessarily wordy and confusing. So, if you’re a European reading this article, just interpret RDA as PRI, EAR as AR, and DRI as DRV.

How RDAs, EARs, and LTIs are determined

If you really want to get into the weeds, a 2010 publication from the EFSA discusses how DRIs are determined in detail. It’s dense, but surprisingly readable. However, most readers probably don’t need to know all of the ins-and-outs of determining DRIs, so I’ll just walk you through the basic steps of the process, using calcium as a model example.

Step 1: Determine the analytical endpoint

To start with, authors decide what endpoint(s) to assess, and the type(s) of evidence that can be used to evaluate the impact of nutrient intake on the relevant endpoint(s).

With calcium, the primary concern is with maintaining bone health. So, you might think that determining intake requirements for calcium would be as simple as looking for research reporting both calcium intake and measures of bone health (bone mineral density, bone mineral content, rates of osteoporosis, etc.), and identifying the level of intake associated with generally positive bone-related outcomes.

However, there are a few problems with that approach. That type of research would only give you a snapshot of a single point in time – bone-related measures typically change very slowly over a period of years, so you’d need to know people’s calcium intake over the entire period in which their bone health was changing. Furthermore, there are numerous confounders. For example, whether or not dietary calcium can be incorporated into your bones depends heavily on vitamin D levels – if you eat a ton of calcium, but you’re deficient in vitamin D, you may still have poor bone health. Similarly, exercise is the main stimulus for bone remodeling – if you consume enough calcium and have sufficient vitamin D levels, but you have a very sedentary lifestyle, you may still have poor bone health.

So, the authors opted to focus on calcium balance studies, where researchers rigorously monitor calcium intake and calcium excretion under controlled conditions. Since the goal of (adult) calcium targets is the maintenance of bone calcium levels, and this type of research can precisely determine the level of calcium intake required to achieve calcium balance (i.e. the point at which the total calcium in the body neither increases nor decreases), it was selected as the primary basis for determining calcium targets.

Step 2: Analyze the data

As mentioned previously, calcium balance studies work by rigorously monitoring calcium intake and excretion. Monitoring calcium intake is simple enough – you monitor the food and beverages subjects consume, and as long as you know the calcium concentrations in all of those foods and beverages, you know how much calcium individuals are consuming.

Monitoring calcium excretion is somewhat gross, but it’s also pretty straightforward. When you consume calcium, your body won’t absorb all of it as it passes through your digestive tract. Some will wind up in your feces. Once absorbed, your body will also excrete excess calcium in your urine. So, to monitor calcium excretion, you need to collect subjects’ urine and feces, and analyze the calcium content in the excrement.

When calcium intake is low, excretion will generally exceed intake. As calcium intake increases, calcium excretion increases, but not quite as fast as calcium intake. So, at some point, excretion will match intake, resulting in neutral calcium balance. However, the point at which excretion matches intake won’t necessarily occur at the exact same level of calcium intake for all individuals – some people may achieve neutral calcium balance at an intake of 600mg/day, while other people may achieve neutral calcium balance at an intake of 900mg/day.

So, to initially determine the EAR, researchers just need to identify the point at which intake matches excretion on average. From there, they calculate the variability in calcium excretion (i.e. they calculate the standard deviation for calcium excretion), and add a margin for safety to accommodate people who excrete more calcium than normal, relative to their intake. That margin for safety is equal to two standard deviations from the mean, to accommodate 95% of individuals in the population. When you add that margin for safety to the EAR you have an initial determination of the RDA and LTI.

Here’s how the calcium balance data looks when graphed out:

Points above the red line are individuals in negative calcium balance, and points below the red line are individuals in positive calcium balance. As you can see, at intakes around 715mg/day (the EAR), about half of the individuals are in positive calcium balance, and about half are in negative calcium balance. Conversely, at intakes above 904mg/day (the RDA), the vast majority of individuals are in neutral-to-positive calcium balance, and only a handful are in negative calcium balance.

Step 3: Final adjustments and rounding

Calcium balance studies have one major blind spot that’s relatively easy to account for. Your body primarily excretes calcium via urine and feces, but you also lose a bit of calcium in your sweat. It’s relatively easy to collect subjects’ urine and feces, but it’s rarely worth worrying about collecting every drop of sweat a subject generates, so calcium balance studies don’t directly monitor calcium losses via sweat. However, the typical calcium loss via sweat is only about 40mg/day. So, the authors of the calcium guidelines compensated for this blind spot in the research by adding 40mg to the intake targets: an EAR of 745mg/day, and an RDA of 944mg/day.

However, humans generally like nice, round numbers. So, the EFSA rounded those figures to an EAR of 750mg/day, and an RDA of 950mg/day. The LTI is the same distance from the mean in the opposite direction, meaning the LTI is 550mg/day.

Of note, those DRIs are for adults over 25 years old. Since younger adults have a greater capacity to gain (not just maintain) bone mass, the authors performed further adjustments to reflect that fact and generate targets consistent with achieving positive calcium balance. For other nutrients, there are additional adjustments for sex, pregnancy status, lactation status.

I realize that the last section may have been a bit overkill, but I think it’s useful for illustrating a few things about micronutrient targets:

1) Nutrient needs differ

DRIs are based on population data, but you’re an individual, not a population. As you can see in the graph above, some folks were in slight positive calcium balance while consuming 600mg/day, while others were in slight negative calcium balance while consuming 1200mg/day. By the very nature of how DRIs work, about half of individuals could consume a bit less than the EAR and be just fine, whereas 2-3% of people would need to consume more than the RDA to ensure their needs are met.

2) The data used to generate DRIs is often relatively imprecise.

Look at the graph above, and try to ignore the blue and red lines. Would an EAR or RDA jump off the screen at you? 

Probably not.

And, for what it’s worth, nutrition researchers will readily admit that the extant data could be used to credibly argue for higher or lower nutrient targets, that “expert opinion” can play a major role in determining the intake targets for some nutrients that lack robust data, and that major judgment calls need to be made for determining the endpoint that guidelines optimize for (i.e. net balance of a particular nutrient vs. blood levels of a nutrient or biomarker vs. clinical endpoints resulting for nutrient deficiency or inadequacy).

I selected calcium for the example above because it’s a nutrient that does have a robust body of research to lean on when generating nutrient recommendations. For nutrients that just have AIs (instead of RDAs), the data is much less robust. In fact, the USDA and EFSA have some disagreements about which nutrients do actually have enough data to warrant RDAs. For instance, the USDA has defined EARs and RDAs for vitamin E and magnesium, but the EFSA has only issued AIs, suggesting that American scientists believe that there is sufficient data to estimate population-level requirements for these nutrients, whereas European scientists believe the data is not yet sufficient to quantify average vitamin E and magnesium intake requirements.

Beyond that, DRIs provide clean numbers that conceal a lot of messiness regarding nutrient sources, bioavailability, and the context of an individual’s diet. For instance, your body absorbs heme iron (the iron present in animal products) much more efficiently than non-heme iron (the iron present in plants), so you could credibly argue DRIs for iron should be higher for vegetarians and vegans than for omnivores. But, for DRIs to be useful public health tools, they need to be simple enough to serve as an easy reference for most individuals in a population. If people needed to go through a multi-step decision tree to figure out their DRIs for most nutrients, very few people would actually bother in the first place. So, having a smaller number of less exact DRIs that do a pretty good job of describing nutrient needs for most individuals is ultimately more useful than having a larger number of more exact DRIs that do a marginally better job of describing nutrient needs in smaller and smaller subpopulations. But, by the same token, there are any number of reasons why your particular micronutrient needs might be higher or lower than the EAR or RDA.

Basically, estimating micronutrient needs and quantifying micronutrient intake targets is a science, but it’s a relatively inexact science.

For a bit of fun reading, you might enjoy this in-depth summary of a conference that served as a retrospective look at the process of developing the US’s DRIs. It covers the decisions researchers made when determining DRIs (and when deciding how to determine DRIs in the first place), debates and disagreements regarding those decisions, and ideas for how the process of determining DRIs could improve in the future.

3) Nutrient guidelines are predicated on cost/benefit analyses, so we should think in terms of ranges rather than exact targets.

No single DRI should be interpreted as the single number to aim for. In fact, the very concept of EARs, RDAs, and LTIs is predicated on the assumption that nutrient needs vary between individuals:

Furthermore, DRIs are based on fundamental concepts of population-level risk assessment and cost-benefit analysis. RDAs are both a) higher than the nutrient needs for most individuals, and b) the lowest targets that ensure that the vast, vast majority of individuals won’t develop nutrient deficiencies (if they meet the RDAs). So, they maximize the benefits for most individuals (avoiding nutrient deficiencies), while minimizing the cost (the literal cost of purchasing and consuming foods that provide way more of a particular nutrient than you actually need). Similarly, as discussed previously, ULs are the highest intake of a particular nutrient that still minimizes risks of an adverse event, but most people can occasionally exceed the UL for a particular nutrient without experiencing any negative effects.

So, instead of looking at the RDA for a particular nutrient and treating it as the single number to aim for, it’s more useful to think of DRIs as sets of numbers that define a range of intake targets.

It’s very likely that you do need to consume more than the LTI, but there’s a pretty decent chance that intakes between the LTI and RDA will be sufficient (with the probability of positive outcomes increasing as you get closer to the RDA or PRI). Similarly, any intake between the RDA and the UL is very likely to have positive effects, and very unlikely to have negative effects, without the probability of positive and negative outcomes significantly varying within that range. In other words, if the RDA for a particular nutrient is 100mg, and the UL is 2000mg, the net effect of consuming 150mg and the net effect of consuming 1500mg should be pretty similar.

Understanding Nutrient Targets and Ranges in MacroFactor

Micronutrient goals in MacroFactor are defined by a range consisting of a floor, a target, and a ceiling.

The floor is typically the LTI, the target is typically the RDA or AI, and the ceiling (if there is a ceiling) is typically the UL.

To generate these ranges, we consulted the DRIs published by the US Food and Nutrition Board, and the DRVs published by the European Food Safety Authority. We wanted the ranges to be as forgiving as they could justifiably be, so when US and European food authorities had slightly different ranges, we typically selected the lower of the two LTIs as the floor, and the higher of the two ULs as the ceiling. But, in the spirit of RDAs and PRIs functioning as “better safe than sorry” intake targets, we typically selected the higher of the two values to serve as the actual target.

To illustrate, here are the American and European DRIs and DRVs for vitamin C:

The American LTIs are lower, so they define the floor of the vitamin C target range in MacroFactor (60mg for men, and 45mg for women). The European PRI is higher than the American RDA, so it serves as the target in MacroFactor (110mg for men, and 95mg for women). Finally, the EFSA hasn’t defined a UL for vitamin C, so the American UL serves as the ceiling in MacroFactor (2000mg for everyone).

When a nutrient has an AI instead of an RDA, that means the LTI isn’t known. In the absence of sufficient data to calculate an EAR and RDA, health authorities typically assume that individual needs vary within a ±20% range. So, we use that assumption for calculating nutrient floors for nutrients that only have AIs.

To illustrate, here are the American and European AIs and implied pseudo-LTIs for potassium:

The European AIs are higher, so they serve as the target in MacroFactor (3500mg for both men and women). The “LTIs” implied by the American AIs are lower, so they serve as the floor (2720mg for men, and 2080mg for women). Neither health agency has put forth a UL for potassium, so there’s no potassium ceiling in MacroFactor.

As one final consideration, both American and European health authorities have set ULs exclusively for synthetic/supplemental forms of some nutrients. For instance, health agencies on both sides of the Atlantic haven’t set a UL for total folate consumption from natural food sources, but they have set a UL of 1000μg/d of synthetic folate coming from supplements or fortified foods. In these instances, the ceiling in MacroFactor is equal to the RDA + the UL for supplemental intake. So, sticking with the folate example, the American RDA (400μg/d) is higher than the European PRI (330μg/d), so the RDA serves as the target. Since the UL for supplemental folate is 1000μg/d, the folate ceiling in MacroFactor is 400 + 1000 = 1400μg/d.

If you’d like to define different nutrient floors, targets, and ceilings for yourself (perhaps you want to stick with exclusively American DRIs or Europeans DRVs, or you have a medical condition that necessitates higher or lower intakes of a particular nutrient), you can adjust those values for yourself in MacroFactor. This knowledge base entry explains how it’s done.

The post Understanding Nutrient Targets appeared first on MacroFactor.

This is part one of a five-part series:
1) Understanding Micronutrient and Essential Nutrient Categories
2) Understanding Nutrient Targets
3) Considerations for Micronutrient Tracking: Precision and Difficulty
4) Which Micronutrients Are Worth Monitoring?
5) Micronutrients are Important, But They Aren’t Everything

Our Knowledge Base also has an archive of additional information about each nutrient you can track in MacroFactor, including what the nutrient actually does, the likelihood of insufficient or excessive intake, and good food sources for each nutrient.

With that out of the way, let’s dive in!

What are Micronutrients?

Micronutrients are elements, chemicals, or substances that are needed for healthy growth and development. But, as the “micro-” prefix implies, micronutrients are substances you don’t need to consume in large quantities. Whereas you’d generally consume dozens or hundreds of grams of each macronutrient (carbohydrates, fats, and proteins) each day, intake requirements for micronutrients are generally measured in milligrams or micrograms.

Most micronutrients are classified as either vitamins or minerals. Vitamins are organic molecules that either can’t be synthesized by the body (like Vitamin C), or can’t be synthesized in sufficient quantities for optimal health (like niacin). Minerals are inorganic elements the body needs from external sources, like calcium, iron, and magnesium.

Vitamins can be further subdivided into water-soluble and lipid-soluble vitamins. Water-soluble vitamins can typically be easily absorbed and readily excreted. Fat-soluble vitamins, on the other hand, are typically absorbed better when consumed along with some dietary fat, and they can typically be stored in the body’s tissues. So, if you consumed a lot of a water-soluble vitamin today, like vitamin C, your vitamin C levels won’t stay elevated for weeks into the future. However, a large dose of a fat-soluble vitamin (like vitamin D) might have effects for weeks (or even months) after consumption.

Water-soluble Vitamins

There are nine water-soluble vitamins:

1. Thiamin (vitamin B1)
2. Riboflavin (vitamin B2)
3. Niacin/Nicotinic Acid (vitamin B3)
4. Pantothenic Acid (vitamin B5)
5. Vitamin B6 (pyridoxal, pyridoxine, and pyridoxamine)
6. Biotin (vitamin B7)
7. Folate/Folic Acid (vitamin B9)
8. Vitamin B12 (various cobalamins)
9. Vitamin C (ascorbic acid). 

All water-soluble vitamins primarily function as important coenzymes, cofactors, or biological precursors to coenzymes or cofactors (substances that make it significantly easier for specific chemical reactions to occur). For example, vitamin C facilitates important chemical reactions involved in building collagen proteins. 

Fat-soluble Vitamins

There are four fat-soluble vitamins:

1. Vitamin A (various retin- compounds, along with provitamin carotenoids)
2. Vitamin D (various calciferols)
3. Vitamin E (various tocopherols and tocotrienols)
4. Vitamin K (various phylloquinones and menaquinones).

Unlike the water-soluble vitamins (which are all cofactors or coenzymes), it’s impossible to broadly classify the function of the fat-soluble vitamins. For example, Vitamin K is broadly similar to the water-soluble vitamins – it primarily functions as a cofactor, and it doesn’t readily accumulate in your body. Vitamin D, on the other hand, is a steroid hormone that can influence gene expression in any cell type with nuclear Vitamin D receptors. Vitamin E primarily functions as an antioxidant, while also regulating an enzyme that influences smooth muscle development.

Minerals

Minerals are a bit trickier to classify than vitamins. Minerals are inorganic elements, rather than organic compounds. We generally consider “minerals” to be elements that are essential for normal health and development, excluding the four major elements found in most organic compounds: carbon, hydrogen, oxygen, and nitrogen.

Of the remaining elements, we know that some are essential for good health (for example, calcium and magnesium), but there’s scientific debate about others (for example, the USDA considered chromium to be an essential element, whereas the EFSA does not). Furthermore, the body seems to be adept at handling even more elements (for example, lithium and boron) in a way that suggests that they may have important biological functions, despite no critical function being identified yet.

So, we know there are at least 15 elements that are essential for human health

1. Sodium
2. Magnesium
3. Phosphorus
4. Sulfur
5. Chlorine
6. Potassium
7. Calcium
8. Manganese
9. Iron
10. Cobalt
11. Copper
12. Zinc
13. Selenium
14. Molybdenum
15. Iodine.

Of those 15, only 14 are generally considered to be “minerals.” Cobalt is incorporated into vitamin B12 (which is an essential vitamin), but there are no known (human) functions of elemental cobalt.

As previously mentioned, there’s not yet a scientific consensus about whether chromium is an essential element – it would be considered a mineral by health authorities in the US, but not in Europe.

Furthermore, there are circumstantial reasons to believe that lithium, boron, fluorine, silicon, vanadium, nickel, bromine, and strontium may be essential elements (in which case, they’d be classified as “minerals”). Basically, your body has tidy ways of handling and excreting these elements, which is generally the case for elements that serve important biological functions, but not for elements that don’t serve important biological functions.

However, specific critical purposes for these elements have not been identified in humans, so it’s possible that these elements were critical for one of our distant ancestors, and that the biological pathways associated with handling these elements have simply been preserved to the present day, despite these elements no longer playing important roles in human health and development. It’s also possible that the body can efficiently handle these elements because they’re chemically similar to other elements the body regularly works with – for example, lithium is in the same column of the periodic table as sodium and potassium, and strontium is in the same column as magnesium and calcium.

So, we don’t actually have a tidy list of elements that should be classified as minerals. There are 14 sure bets, with another 9 “maybes.”

Much like fat-soluble vitamins, minerals serve a variety of different purposes. For example, calcium is necessary for bone health, and is also critical for allowing muscles to contract. Sodium and potassium are necessary for maintaining a bioelectrical potential across the membranes of nerve and skeletal muscle cells. Chlorine is critical for digestion, as a necessary component of stomach acid. Iron is an important component of hemoglobin and myoglobin, which your body uses to transport oxygen. Many other minerals function as cofactors for various chemical reactions.

Other essential nutrients

While vitamins and minerals get most of the attention, there are several other nutrients that play vital roles in health and development.

Essential fatty acids are types of fat that are necessary for optimal health and normal physical functioning, but that the body can’t manufacture. In that way, they’re functionally similar to vitamins. These essential fatty acids are classified as omega-3 (EPA, DHA, and ALA) and omega-6 (linoleic acid) fatty acids. They have a wide array of functions in the body, but are primarily implicated in regulating and influencing pro- and anti-inflammatory processes.

Essential amino acids are amino acids (building blocks of proteins) that the body can’t produce on its own, meaning they need to be consumed from food sources. Of the 20 amino acids used to build proteins in the body, 9 are considered essential:

1. Histidine
2. Isoleucine
3. Leucine
4. Lysine
5. Methionine
6. Phenylalanine
7. Threonine
8. Tryptophan
9. Valine

Furthermore, six other amino acids are considered conditionally essential – the body can usually synthesize these amino acids in sufficient quantities, but there are situations where it may not be able to (for example, due to advanced age or certain liver conditions). The conditionally essential amino acids are:

1. Arginine
2. Cysteine
3. Glutamine
4. Tyrosine
5. Glycine
6. Proline

Insufficient intake of essential amino acids will prevent your body from being able to build or repair certain proteins. For example, rice protein is very low in lysine, so lysine deficiencies are reasonably common in parts of the world that rely almost exclusively on rice to meet people’s energy needs. Lysine is necessary for collagen synthesis, so a lysine deficiency can lead to connective tissue disorders. Lysine is also used to create proteins that are necessary for fatty acid metabolism, so a lysine deficiency can lead to liver damage.

Essential fatty acids and amino acids must be consumed via diet because the body isn’t capable of synthesizing them. However, there are a few other molecules that the body can synthesize, but which it may not synthesize in sufficient quantities for optimal health.

Choline: the “other” essential nutrient

Choline exists in a state of limbo. It’s basically a vitamin, though medical and scientific organizations haven’t classified it as such. Your body can produce choline in the liver, but it doesn’t produce enough for optimal health (much like niacin). So, despite not fitting neatly into any of the other “essential nutrient” categories (vitamins, minerals, essential fatty acids, essential amino acids), choline is still considered an essential nutrient.

Choline is required to produce two different phospholipids that help preserve the structural integrity of cell membranes. Choline is also the core component of acetylcholine – one of the most abundant neurotransmitters.

Other nutrients that may be “conditionally essential”

Essential nutrients (like vitamins, minerals, essential amino acids, and essential fatty acids) are nutrients the body either can’t produce on its own, or nutrients that the body can’t produce in adequate quantities for optimal health. However, that’s a hazy boundary. As seen previously, some amino acids are “conditionally essential,” meaning that the body can generally produce those amino acids in sufficient quantities for optimal health, but that it can’t always produce those amino acids in sufficient quantities for optimal health.

With that in mind, there are other nutrients that may be conditionally essential – your body can produce these nutrients, but may not always produce them in sufficient quantities for optimal health.

Choline used to fall under this umbrella, until it was re-classified as an essential nutrient in 1998.

Creatine and carnitine are two nutrients that fall under this umbrella today. Both serve important purposes in the body (creatine helps maintain cells’ energy supply, and carnitine helps with fatty acid metabolism), both can be produced by the body, but the body may not always produce sufficient quantities of both of these nutrients for optimal health.

For example, low creatine intake is associated with an elevated risk of depression. Furthermore, early data suggest that creatine supplementation may help alleviate depressive symptoms (which would further suggest that the association between creatine intake and depression is indicative of a causal link, rather than being a mere association). However, most people with low creatine intake don’t exhibit depressive symptoms, thus suggesting that creatine may be a conditionally essential nutrient. For even more arguments in favor of creatine being considered a conditionally essential nutrient, you may enjoy a 2022 review from Ostojic and Forbes.

Carnitine is already firmly “conditionally essential,” but only in very specific situations. For example, some kidney diseases increase carnitine excretion, so people with those specific kidney diseases need to take supplemental carnitine. However, an argument could be made that carnitine is also conditionally essential for individuals with conditions (like metabolic syndrome and type 2 diabetes) that cause mitochondrial dysfunction. Multiple meta-analyses have found that carnitine supplementation can help improve insulin resistance and blood glucose regulation in individuals with obesity, type 2 diabetes, and insulin resistance. So, it’s possible that these individuals don’t produce enough carnitine for optimal health, and carnitine may eventually be classified as conditionally essential within those populations.

To be clear, this isn’t an exhaustive list, and I’m also not claiming that creatine and carnitine have been misclassified by the scientific bodies that designate nutrients to be essential or conditionally essential. I’m merely noting that micronutrient research is still an active concern, and the list of nutrients considered to be essential or conditionally essential can change over time. As mentioned previously, the US and Europe currently disagree about how to classify chromium. Furthermore, choline was only added to the list of essential nutrients in 1998. So, it’s entirely possible that other nutrients will be added to these lists over time.

The next article in this series will discuss nutrient targets: where they come from, what they mean, and how to think about them.

The post Understanding Micronutrient and Essential Nutrient Categories appeared first on MacroFactor.