Published on January 17, 2021

Which nutrients are you most at risk of not getting enough of, and how does that risk change with weight?

Several previous posts have discussed how body weight or body mass index (BMI) affects your vitamin D level – those with a higher BMI tend to need more vitamin D and be at a greater risk for vitamin D deficiency. In fact, an analysis of GrassrootsHealth data showed that the amount of vitamin D needed on a daily basis to achieve a vitamin D level of 40 ng/ml (100 nmol/L) can vary by as much as 3 times the amount, depending on BMI.

With BMI having such an effect on the vitamin D dose response, it makes sense that suggesting the same daily intake of vitamin D for all adults simply will not work. If this is true of vitamin D, is it also true for other nutrients? Are there other nutrients that overweight and obese individuals are at risk of being deficient in?

Greater Risk of Nutrient Inadequacies with Higher BMI

A cross-sectional study by Jun et al. published in 2020 evaluated nutrient levels and intakes of adults ages 60 years and older in the United States (n=2969) using the National Health and Nutrition Examination Survey (NHANES) 2011-2014 data based on BMI – they compared intakes between overweight or obese individuals and individuals of a healthy weight. Nutrients evaluated were those identified as “under-consumed nutrients” by the Dietary Guidelines for Americans or those of increased risk for inadequacy in adults, which consisted of calcium, magnesium, zinc, vitamin A, folate, vitamin B6, vitamin B12, vitamin C, vitamin D, and vitamin E. Intake from both diet and supplements was evaluated, and blood levels were measured for folate, vitamin B12, and vitamin D.

Which Nutrients Were At Greatest Risk of Inadequacy?

The study found that overall, among older adults who were 60 years of age or older with a BMI of at least 18.5 (which includes all weight groups except those who were underweight), all were at risk of not getting enough calcium, magnesium, vitamin C and vitamin D on a daily basis, from both diet and supplements. Those who were obese were at even greater risk of not getting enough of each nutrient examined, especially among women.

Looking at diet alone, compared to healthy weight individuals, those who were obese were at greater risk of not getting enough magnesium, calcium, vitamin B6, and vitamin D. Men were more likely to not get enough vitamins C and E, while women were more likely to not get enough vitamins B6 and D. When including nutrient intake from supplements, a substantial proportion were still at risk of inadequate amounts of calcium, magnesium, vitamin C and vitamin D.

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In terms of blood levels of vitamin D, obese women were twice as likely to have a level below 16 ng/ml or 40 nmol/L (12%) compared to healthy-weight women (6%). Average vitamin D levels were significantly lower in obese overall compared to both overweight and healthy weight older adults. The risk of folate deficiency and vitamin B12 deficiency was low across all groups.

Nutrients Important for Immune Function

The findings presented above are similar to those found in a previously reviewed paper, which looked at intakes of vitamins A, C, D, E and zinc among adults in the general population (ages 19 and older), due to their well-known roles in immune function. They found that intakes of certain nutrients, such as vitamin C, vitamin D, and zinc, are much lower than expected from previous reports.

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The chart above shows the inadequate intakes for each nutrient, based on intake from food alone and from food plus dietary supplements. While supplements do help bridge the gap for some, many are still left with inadequate intake of several key nutrients, especially vitamin D.

As quoted by the authors:

“Micronutrients are a fundamental part of the immune system and require optimal levels for effective immune function. Nutrient insufficiency/deficiency of one nutrient can adversely affect immune health, while multiple inadequacies may put the immune system at a bigger deficit.”

Make sure you are getting enough vitamin D and other important nutrients!

By joining the GrassrootsHealth projects, you are not only contributing valuable information to our study, but you are also gaining knowledge about how you could improve your own health through measuring and tracking your nutrient status, and educating yourself on how to improve it. Do you know what your status of vitamin D, omega-3s, and other essential nutrients is? Could your levels be improved? Test now to find out!

We now have a NEW GIFTING SERVICE that allows you to quickly send ‘Gift Cards’ to friends, family and coworkers who you consider might need immediate access to testing, and to Claim the Joy of Your Health TODAY. Give the gift today!

What does the Research Say about Vitamin D & COVID-19?

It’s TIME to start saving lives! If you can help PREVENT the majority of the death, it’s time! What’s it costing you/us not to take action NOW?

There is much published research that supports a clear link between vitamin D and COVID-19 showing that higher vitamin D levels are related to:

a decreased risk of testing positive for COVID-19

increased viral SARS-CoV-2 RNA clearance

better clinical outcomes among patients with COVID-19

less severe COVID-19 disease

decreased risk of death due to COVID-19

Be sure to educate yourself on the benefits and importance of vitamin D for immune health, and take steps to ensure you and your loved ones are getting enough.

You can review all of the COVID-19 and immune health information we have shared on this page.

What Does it Take YOU to Get Your D to 40 ng/ml (100 nmol/L)?

Did you know your health could be greatly affected by making sure you have a vitamin D level of at least 40 ng/ml (100 nmol/L)? Help us help you.

STEP 1 - Do you know what your vitamin D level is? If not, be sure to test today to find out.

STEP 2 – Determine your target level. Are you at your target level? Experts recommend a level of at least 40-60 ng/ml (100-150 nmol/L).

STEP 3 – Need to boost your level? Use the D*calculator to see how much vitamin D it may take to reach your target. Opt for the Loading Dose for a quicker boost.

STEP 4 – Optimize how your body absorbs and utilizes vitamin D with co-nutrients and these simple steps.

STEP 5 – Re-Test! This is an important step to make sure you have reached your target level, and to ensure you are not taking too much! Re-testing after 3-4 months is recommended.

STEP 6 – Adjust, Repeat…

Give your immune system the nutrients it needs to support a healthy you and protect yourself from unnecessary diseases, especially COVID-19.


The first Randomized Controlled Trial on vitamin D and COVID-19 has shown a 96% lower risk of ICU admission for those receiving vitamin D (as 25(OH)D to quickly boost vitamin D blood levels) along with the standard treatment, compared to those receiving standard treatment alone.

These results support many previous observational studies showing a relationship between vitamin D levels and intake and COVID-19 severity.

Review the Latest Nutrient Research for COVID-19

GrassrootsHealth Nutrient Research Institute has launched the new Immune Boost project with the use of our myData-myAnswers nutrient health system that nearly 15,000 people are already using for their health. Specific markers that influence immune health are suggested for testing as part of this project including:

  • Vitamin D
  • Omega-3 Index
  • Essential elements magnesium, selenium, and zinc
  • hsCRP

Our goal is to demonstrate how one can use the Nutrient Research Model established by Dr. Robert Heaney to show the effect of vitamin D serum levels of at least 40 ng/ml (100 nmol/L) on risk reduction for all ethnicities in the population. Status and intake of other nutrients will also be analyzed for any type of relationship to immune status and symptom severity. Join the project today!

Please let us know if you're interested in helping sponsor this project.

CLICK HERE for updates and new information about the project.

Through GrassrootsHealth Nutrient Research Institute, you can also test your essential elements magnesium, copper, zinc and selenium, toxins such as lead, mercury and cadmium, as well as your omega-3 levels, inflammation levels and thyroid stimulating hormone (TSH) level. Find out your levels today! Log on to the test selection page (click the link below) to get your tests and see for yourself if your levels can be improved.

Make sure you track your results before and after, about every 6 months!

Click Here to Access the Test Page

How can I track my nutrient intake and levels over time?

To help you track your supplement use and nutrient levels, GrassrootsHealth has created the Personal Health Nutrient Decision System called

For each specific supplement, you can track what days you take it, how much, and many other details.  This will help you know your true supplemental intake and what patterns of use work for you to reach and maintain optimum nutrient levels. Check it out today!