Maintaining adequate levels of essential vitamins and minerals is extremely crucial for good health. This has also been highlighted by Havard School of Public Health in their Food Pyramid. It is common in the general population, especially the elderly to have suboptimal intake of some vitamins which is a risk factor for chronic diseases. On top of it, micronutrient adequacy has the potential to extend lifespan – recent research has found that multivitamin use is associated with longer telomere length in women (an indicator of a slower rate of aging) and this has also been highlighted in my previous article.
Of course, in addition to vitamins and minerals, a diet full of colorful natural plant foods is still needed because multivitamins cannot and will not replace your daily intake of healthy natural food. But the truth is that there are some nutrients that are lacking even in an ideal diet and deficiencies in certain nutrients can undermine your health causing various chronic diseases. On top of that, we cannot be sure that we are getting the precise optimal amounts of vitamins and minerals from our diet everyday – especially since absorption efficiency and utilisation of nutrients varies from person to person. For example, someone who has gastrointestinal issues like inflammatory bowel disease (IBD) will have decrease absorption of nutrients, so just having a healthy diet will not be sufficient. A high quality multivitamin can fill these gaps, ensuring that we get adequate amounts of essential micronutrients.
Some vitamins and minerals are often lacking even in a healthy diet:
Vitamin D is definitely at the top of the list. It was once thought to be important only for bone health, now scientists have found that Vitamin D has important actions in almost every cell in the human body, regulating the expression of over 200 different genes, including the ones related to apoptosis and immune modulation (1). Insufficient vitamin D levels are associated with several cancers, diabetes, cardiovascular disease, depression, and autoimmune diseases. Today, a lot of people suffer from insufficient Vitamin D levels with nearly 1/3 of Australian adults suffering Vitamin D deficiency according to a recent study by Deakin University. Since many of us live in cool climates and work indoors, and because of the potential risks of skin damage and skin cancer with sun exposure, supplementing is the best choice for achieving adequate vitamin D levels. In my experience, 2000 IU has been an appropriate dose to bring most people into the favorable blood 25(OH)D range of 50-75nmol/L. For extra assurance, I’ve also utilized Vitamin D3 because of its high biological value, the most effective form for raising 25(OH)D levels (2).
Vitamin B12 is required for important biological functions like red blood cell production, nervous system function, and DNA synthesis. Insufficient B12 levels are also associated with increased risk of Alzheimer’s disease (3). Deficiency in B12 can cause a variety of health problems including elevated homocysteine (a cardiovascular risk factor), anemia, depression, confusion, fatigue, digestive issues, and nerve damage (4).
Vitamin B12 is unique in that it is made only by microorganisms. Today, we live in a sterile polluted environment where our food is scrubbed (generally with chemicals) ‘clean’ of any soil and B12 possibility and due to the fact that our produce is washed and often transported far before we eat it (soil contains B12-producing microorganisms), most of us are unable to get sufficient B12 from plant foods alone. B12 deficiency is common, especially in vegans who don’t supplement and in the elderly (ability to absorb B12 decreases with age) and about 20% of adults over the age of 60 are either insufficient or deficient in vitamin B12 (5). Supplementation with vitamin B12 is important for most people, and absolutely required for most vegans to achieve sufficient B12 levels.
Iodine is required by the body to make thyroid hormones. A recent study of vegans estimated that only about 40% of the daily requirement for iodine was commonly met on a vegetarian or vegan diet (6). Another study concluded that 80% of vegans, 25% of vegetarians, and 9% of conventional eaters are iodine-deficient (7). Most plant foods are low in iodine due to soil depletion. The chief source of iodine in the typical diet is iodised salt. Since salt should be avoided for general good health, it is important to supplement with iodine to maintain adequacy.
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 (8). A recent study of vegetarians found a high prevalence of zinc deficiency, and zinc requirements for those on a completely plant-based diet are estimated to be about 50% higher than the US RDI (9).
1: Hyppönen E. Vitamin D and increasing incidence of type 1 diabetes-evidence for an association? Diabetes Obes Metab. 2010 Sep;12(9):737-43. doi: 10.1111/j.1463-1326.2010.01211.x.
2: Tripkovic L, Lambert H, Hart K, Smith CP, Bucca G, Penson S, Chope G, Hyppönen E, Berry J, Vieth R, Lanham-New S. Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. Am J Clin Nutr. 2012 Jun;95(6):1357-64. doi:10.3945/ajcn.111.031070. Epub 2012 May 2.
3. Hooshmand B, Solomon A, Kåreholt I, Leiviskä J, Rusanen M, Ahtiluoto S, Winblad B, Laatikainen T, Soininen H, Kivipelto M. Homocysteine and holotranscobalamin and the risk of Alzheimer disease: a longitudinal study. Neurology. 2010 Oct 19;75(16):1408-14. doi: 10.1212/WNL.0b013e3181f88162.
4. Office of Dietary Supplements, National Institutes of Health. Dietary Supplement Fact Sheet: Vitamin B12
5. Allen LH. How common is vitamin B-12 deficiency? Am J Clin Nutr. 2009 Feb;89(2):693S-6S. doi: 10.3945/ajcn.2008.26947A. Epub 2008 Dec 30.
6.:Waldmann A, Koschizke JW, Leitzmann C, Hahn A. Dietary intakes and lifestyle factors of a vegan population in Germany: results from the German Vegan Study. Eur J Clin Nutr. 2003 Aug;57(8):947-55.
7. Krajcovicová-Kudlácková M, Bucková K, Klimes I, Seboková E. Iodine deficiency in vegetarians and vegans. Ann Nutr Metab. 2003;47(5):183-5.
8. Hunt JR. Bioavailability of iron, zinc, and other trace minerals from vegetarian diets. Am J Clin Nutr 2003;78(suppl):633S–9S.
9. de Bortoli MC, Cozzolino SM. Zinc and selenium nutritional status in vegetarians. Biol Trace Elem Res. 2009 Mar;127(3):228-33. doi:
10.1007/s12011-008-8245-1. Epub 2008 Oct 25.
Dr Nicole Ng (MBBS) is a medical doctor with a passion in women's health and medical research