Why Take a Multivitamin?

April 22, 2021 by Joel Fuhrman, MD


Dr. Fuhrman’s Guide to Smart Supplementation

The Nutritarian diet is designed to fuel our bodies with high-nutrient plant foods and super-charge our immune defenses. This helps us reach our ideal weight, reverse and protect against chronic diseases, and age slowly. This eating style emphasizes colorful plant foods that provide us with thousands of beneficial phytochemicals while avoiding foods that may harm us. It is a diet designed to give us the happiest life possible. Scientific studies suggest that those who eat more whole plant foods live longer.1-5

As we increase the proportion of these life-protective plant foods and reduce animal products we slow aging and get further healthy life expectancy; however, the reduction and elimination of most animal-sourced foods reduce our exposure to certain beneficial nutrients such as zinc, B12, DHA, iodine and a few others.  With the high plastic contamination of seafood and carcinogenic effects of meats, it is a more logical, earth sustainable and healthier option to optimize levels of these nutrients with supplements. With smart supplementation, we do not need to add animal products to our diets for these valuable nutrients. 

This means that the ideal diet for longevity is so plant-rich that it requires only conservative and judicious supplementation to make it 100% effective and protective. Supplementation is a more sensible choice compared to trying to add enough seafood or meat to source these nutrients. 

Deficiencies, even mild insufficiencies, of B12, zinc, iodine and DHA, can undermine our health. However, with the right supplementation, we can ensure we are using the advances in nutrition science and the ability of testing to optimize nutrient levels in the body to assure we not only protect against nutritional deficiencies, but achieve the optimal levels for maximizing our health, performance and longevity.

Vitamin deficiencies and insufficiencies increase the risk of chronic diseases. Inadequate vitamin and mineral intake is also common in the general population, even in those eating more animal products.6 

In contrast, consuming an nutrient rich, plant-based diet with the appropriate amounts of vitamins and selected minerals has the potential to extend lifespan dramatically. Recent research concluded multivitamin use is associated with longer telomere length, which is an indicator of a slower rate of biological aging.7

Of course, do not forget that conventional multivitamins use cheap synthetic ingredients and contain vitamins that can increase cancer risk, such as folic acid and synthetic Vitamin A derivatives, so which multi you take can be a matter of life or death.   

Action Item:
General Supplement Guidelines

Sources:
Ten years of life: Is it a matter of choice?
Does Nut Consumption Reduce Mortality and/or Risk of Cardiometabolic Disease? An Updated Review Based on Meta-Analyses 
Plant-Based Diets Are Associated With a Lower Risk of Incident Cardiovascular Disease, Cardiovascular Disease Mortality, and All-Cause Mortality in a General Population of Middle-Aged Adults 
Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality-a systematic review and dose-response meta-analysis of prospective studies 
Legumes: the most important dietary predictor of survival in older people of different ethnicities
Foods, fortificants, and supplements: Where do Americans get their nutrients?
Multivitamin use and telomere length in women

5 Vital Vitamins and Minerals

We cannot be sure that we are getting the precise and optimal amounts of vitamins and minerals every day from our diet, since absorption efficiency and utilization of nutrients varies from person to person. A high-quality multivitamin can fill these gaps, ensuring that we get adequate amounts of essential micronutrients. 

The following vitamins should be found in your multivitamins in optimal amounts:

Vitamin B12

Vitamin B12 is required for important biological functions like red blood cell production, nervous system function, and DNA synthesis. Deficiency in B12 can cause a variety of health problems, including anemia, depression, confusion, fatigue, digestive issues, and nerve damage.8 Insufficient B12 levels increase homocysteine – a risk factor for cardiovascular disease, also associated with cognitive decline and dementia,9 and are also associated with increased risk of Alzheimer’s disease.10

Vitamin B12 is made only by microorganisms. Because our produce is washed and often transported much before we eat it (soil contains B12-producing microorganisms), most of us are unable to get B12 from plant foods. B12 deficiency is common, especially in vegans who don’t supplement and in the elderly, since absorption efficiency decreases with age. Our ability to absorb B12 decreases with age, and about 20 percent of adults over the age of 60 are either insufficient or deficient in vitamin B12.11 Supplementation with vitamin B12 is likely important for most people, since research suggests we absorb only a small proportion of B12 ingested, and absolutely required for most vegans.12,13 I recommend approximately 75 mcg B12 daily for most healthy people. 

Sources:
The metabolism and significance of homocysteine in nutrition and health 
Cognitive impairment and vitamin B12: a review 
How common is vitamin B-12 deficiency? 
Vitamin B12 in health and disease

Vitamin D

When exposed to the sun, our skin makes vitamin D. Once thought to be important only for bone health, scientists have now found that vitamin D has important actions throughout the body, and low vitamin D levels are associated with diminished immune function, several cancers, diabetes, cardiovascular disease, and autoimmune diseases.14,15

Related: Vitamin D is Crucial to Overall Health

Insufficient vitamin D levels are also very common.14 Since many of us live in cool climates and work indoors, and because of the potential risks of skin damage and skin cancer from too much sun exposure, supplementing is the best choice for achieving adequate vitamin D levels. In my experience, 2000 IU (50 mcg) has been an appropriate dose to bring most people into the favorable blood 25(OH)D range of 30-45 ng/ml (I also recommend getting a blood test to confirm adequate levels). For extra assurance, I also utilize (vegan) vitamin D3 in my multivitamins because of its high biological value. It is the most effective form for raising 25(OH)D levels.16

Sources:
Vitamin D: Update 2013: From rickets prophylaxis to general preventive healthcare
Vitamin D for skeletal and non-skeletal health: What we should know
Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis

Vitamin K2

There are two forms of vitamin K: K1 and K2. Vitamin K1 is abundant in leafy green vegetables, so those who follow a healthful diet do not need to supplement with K1. Vitamin K2 – which is produced by microorganisms and is low in plant foods – is more important to supplement on a Nutritarian diet. Vitamin K is important for blood coagulation, cardiovascular health, and bone health.17 Vitamin K2 supplementation may also offer additional health benefits beyond those of K1 alone.18,19 

Related: What is vitamin K? Do I need both K1 and K2?

Vitamin K2 supplementation reduced the risk of fracture, reduced bone loss, and increased bone mineral density in studies on adults with osteoporosis.20-24

In the cardiovascular system, vitamin K helps prevent coronary artery calcification.25 In several studies, vitamin K2 intake was associated with reduced risk of heart disease. Some evidence suggests K2 is more protective than K2, but this issue remains unclear.18,26,27 The human body can synthesize some K2 from K1, and intestinal bacteria can produce some usable K2, but these are very small amounts.28 Therefore, it is likely important to supplement with K2. There is no recommended daily allowance for vitamin K2 specifically; a reasonable daily dose is likely 30-40 mcg, which would represent about one-third of the recommended daily vitamin K intake. 

Sources:
The role of menaquinones (vitamin K(2)) in human health
Vitamin K2 Needs an RDI Separate from Vitamin K1
Vitamin K intake and the risk of fractures: A meta-analysis
Does vitamin K2 play a role in the prevention and treatment of osteoporosis for postmenopausal women: a meta-analysis of randomized controlled trials
Quantifying dietary vitamin K and its link to cardiovascular health: a narrative review

Iodine

Iodine is required by the body to make thyroid hormones. A vegan or near-vegan diet, especially one that avoids table salt, may be low in iodine.29,30

Most plant foods are low in iodine. An exception is kelp, a sea vegetable that is a good source of iodine, but kelp is not commonly eaten on a regular basis and may actually provide excessive amounts of iodine. The chief source of iodine in the typical American diet is iodized salt. Since added salt should be avoided to prevent elevated blood pressure, arterial stiffness, and other negative effects, it is important to supplement with iodine for the optimal amounts, approximately 150 mcg/day.

Sources:
Office of Dietary Supplements, National Institutes of Health. Dietary Supplement Fact Sheet: Iodine 
Vegans, Vegetarians, and Omnivores: How Does Dietary Choice Influence Iodine Intake? A Systematic Review 

Zinc

Zinc is essential for immune function, growth, and reproduction, and supports hundreds of chemical reactions. Zinc is abundant in whole plant foods, but is not readily absorbed. Beans, whole grains, nuts, and seeds contain zinc, but also contain substances that inhibit zinc absorption. Zinc intake and circulating zinc levels are lower in vegetarians and vegans,31,32 and zinc requirements for those on a completely plant-based diet are estimated to be about 50 percent higher than the standard recommendations.33-35

Zinc adequacy is especially important for men, because it is concentrated in the prostate where it has protective effects against prostate enlargement and prostate cancer.36  A reasonable supplemental dose to complement a Nutritarian diet is 7.5-10 mg zinc daily.

Sources:
Effect of vegetarian diets on zinc status: a systematic review and meta-analysis of studies in humans
The role of zinc in life: a review
Zinc Deficiency in Men Over 50 and Its Implications in Prostate Disorders

An Important Note on DHA/EPA

In this article, I am highlighting important information regarding multivitamins, but I wanted to take a moment to speak about the importance of DHA and EPA. 

The long-chain omega-3 fatty acids DHA and EPA are associated with many aspects of brain health. I recommend supplementing with these beneficial fats, since most modern diets are low in DHA and EPA unless fish is consumed regularly. Research confirms that vegans tend to have a low omega-3 index.37 

No matter what your age, maintaining adequate omega-3 stores is crucial for the current and future functionality of your brain and life health. A Nutritarian diet provides many nutrients that benefit brain health, but is low in pre-formed DHA and EPA since frequent fish consumption is discouraged. Algae-based supplements are preferable to fish, to avoid excess animal protein and pollutants, such as dioxin and mercury, present in fish.  

Related: Omega-3 fatty acids, DHA and EPA, are crucial for brain health through all stages of life 

Action Item:
Shop DHA+EPA Purity

Choosing the right multivitamin

Although I recommend a multivitamin to fill some nutritional gaps, it is important to choose the right one. Just as it is important to make sure we are getting important nutrients that are lacking, it is equally important to avoid consuming excessively high levels of certain nutrients. There are even ingredients to steer clear of completely because  they may do more harm than good. 

3 ingredients you don’t want in your multivitamin 

Do not take a multivitamin containing folic acid, vitamin A, or beta carotene.

Folic Acid

Synthetic folic acid found in many supplements and food products is not the same as natural folate, which is found in high concentrations in green vegetables and other plant foods. Luckily, Nutritarians have their fill of green vegetables and do not need to worry about obtaining folate as it is plentiful in plants. Folate is especially important for women of childbearing age, to prevent against birth defects, and adequate folate intake helps protect against cancers. However, there is evidence that synthetic folic acid, due to its higher bioavailability, may have cancer-promoting effects.38-40 

Sources:
Is folic acid good for everyone?
Folate and cancer prevention: a closer look at a complex picture

Vitamin A and Beta-Carotene

There is no need to supplement with beta-carotene or vitamin A on a Nutritarian diet, since beta-carotene and other provitamin A carotenoids are plentiful in orange, yellow, and green vegetables and fruits. Research suggests vitamin A and beta-carotene in supplement form increase the risk of cancers, possibly by interfering with the absorption of other carotenoids with anti-cancer properties.41 Studies also suggest vitamin A supplementation contributes to osteoporotic fractures,42 may have cancer-promoting effects,43 and especially at higher doses, both vitamin A and beta-carotene are associated with an increase in risk of premature death.43, 44 

Sources:
Beta-carotene, carotenoids, and disease prevention in humans
Vitamin A intake and osteoporosis: a clinical review
Dietary Supplements and Risk of Cause-Specific Death, Cardiovascular Disease, and Cancer: A Systematic Review and Meta-Analysis of Primary Prevention Trials 

Caution: vitamin E, selenium, iron, and copper

Vitamin E in its many forms is plentiful in nuts and seeds. However, supplementation with alpha-tocopherol only (the primary supplemental form of vitamin E) in high doses is linked to increased mortality risk.44 We need sufficient but not excessive amounts of selenium (which is present in nuts, beans, and whole grains); selenium levels that are too high are linked to diabetes, elevated cholesterol, prostate cancer, cardiovascular disease, and impaired immune and thyroid function.45-50 Iron and copper are essential for the proper function of many chemical reactions in several of the body’s cells and tissues. However, as we age, excess amounts of these metals may build up and become toxic, contributing to oxidative stress that promotes cardiovascular disease and neurodegenerative diseases.51-53 Iron should only be taken in the case of deficiency or an increased biological requirement, such as in pregnancy.54,55   

Related: Iron recommendations for pregnant women

Sources:
Meta-regression analyses, meta-analyses, and trial sequential analyses of the effects of supplementation with beta-carotene, vitamin A, and vitamin E singly or in different combinations on all-cause mortality: do we have evidence for lack of harm?
Adverse health effects of selenium in humans 
Metal Toxicity Links to Alzheimer's Disease and Neuroinflammation
New insights into the role of iron in inflammation and atherosclerosis 
Iron status during pregnancy: setting the stage for mother and infant 

Takeaway

These surprising scientific findings mean that most conventional multivitamins act as a double-edged sword, containing both helpful and harmful elements. Use the latest advance in nutritional research to your advantage by understanding the ingredients found in your multivitamin and making sure that they are present in optimal amounts. It is this reason I created my own multivitamins for my patients to ensure that they supplement wisely.  

Action Item:
Shop Multivitamins

 

 
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Joel Fuhrman, M.D. is a board-certified family physician, seven-time New York Times bestselling author and internationally recognized expert on nutrition and natural healing, who specializes in preventing and reversing disease through nutritional methods. Dr. Fuhrman coined the term “Nutritarian” to describe his longevity-promoting, nutrient dense, plant-rich eating style.
 
For over 25 years, Dr. Fuhrman has shown that it is possible to achieve sustainable weight loss and reverse heart disease, diabetes and many other illnesses using smart nutrition. In his medical practice, and through his books and PBS television specials, he continues to bring this life-saving message to hundreds of thousands of people around the world.

 

Comments (0):

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Jill Gaffney

04/27/2021 03:25 PM

I have been on your nutritarian diet for over two years and am so grateful for your guidance. I have lost weight and lowered my cholesterol but my plasma levels are very low around 120. Can you recommend a supplement or foods to eat or avoid?

Jenna F. replies:

04/28/2021 10:35 AM

If you're looking for the proper supplements, click here for the Vitamin Advisor!  That will help :)

ronalexander

05/06/2021 09:53 AM

You say that we used to get the needed B12 from soil or water, but not anymore. But there is not a reference for this. Was the B12 in soil really a sufficient source in preindustrial times? Or did we use to get really the majority of B12 from insects and small animals instead? 

 

This comment was last edited on 05/06/2021 09:54 AM

Dr. Ferreri replies:

05/06/2021 04:32 PM

It was likely a combination, since there were probably no or few early humans eating only plants. Bacteria in the digestive tract also produce some B12, and this is a major source for some herbivorous animals. The point is that early humans would have gotten some B12 from bacteria present on edible plants, but humans today generally won't; plants themselves do not produce B12 and neither do animals, only microorganisms do. We've updated the wording to be more clear. 

Some more info: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5788147/