Why taking a daily multivitamin is necessary
July 21, 2011

multivitamin

 

The usefulness of multivitamin supplementation has been debated for many years. Studies, predominantly retrospective in nature, have suggested a benefit for those taking certain supplements. Thus, vitamin supplementation has grown in popularity among consumers over the past decade. A Canadian study from 2002 clearly demonstrates that taking a multi-nutrient formulation may actually be the only way the average person can reach the recommended daily intake of nutrients. The recommendations outlined in the new Dietary Reference Intakes (DRIs) are, for several nutrients significantly different to the previous Recommended Dietary Allowances (RDAs).

The new recommendations aim to define nutritional adequacy as that which not only prevents deficiency but also maintains wellbeing and promotes health by optimizing nutrient intake for the prevention of heart disease, birth defects, certain forms of cancer, and other diseases. Using random sampling, a study of 1530 adults found that taking a daily multi-nutrient formulation is associated with an increase chance of obtaining the Recommended Daily Allowance (RDA) of certain nutrients. Supplement users had dietary intakes from their food similar to non-users with mean intakes in some age/sex groups below the RDA/AI for iron, calcium and folate but this was corrected by taking multi-nutrient supplementation.

The study found that multi-nutrient users have higher total intakes of folate, iron, calcium and iron.   In women aged 19-50, only 19% of the women who did not take nutrient supplements attained RDA levels versus 80% of women who did. A similar difference can be seen for both men and women in terms of having below Estimate Average Requirements (EARs). For folate and calcium the difference is even more extreme in both men and women.

The study also confirms that the addition of Vitamin D is essential for reaching AI for Calcium (see tables below). Only 28% of the multi-nutrient formulations reported in the study contained zinc, so mean total intake levels were not significantly higher than dietary intake among multi-nutrient users as a group. A properly designed multi-nutrient formulation should of course contain adequate levels of this important mineral. Special groups with special needs Children & adolescents Adequate consumption of vitamins and minerals is essential for the optimal performance of a host of physiological processes that have both direct and indirect effects on brain function, yet the modern diets of children and adolescents predispose individuals to deficiencies in one or more micronutrients. And supplementation may be the only way to guarantee that a child receives its daily nutrient requirement.

The cognitive and mood enhancing effects of a daily multi-nutrient formulation were recently tested in children. 96 school children received a supplement containing a selection of vitamins and mineral or matched placebo for 12 weeks. Cognitive performance was assessed using a variety of tests. Results showed that, compared to placebo, participants in the active group performed better on the attention tasks throughout the assessments. There were, however, no significant changes on measures of mood or fatigue. Women The majority of patients presenting to their medical practitioners in Australia have one or more nutritional deficiencies. Prescribed medication can compound these deficiencies and therefore contribute to many degenerative diseases. Women taking contraceptive pill for example have lower zinc, folate, B1, B2, B6, B12, vitamin C and E levels. Folate supplementation in contraceptive pill users with normal blood folate can result in improved cervical cytology.

Pregnancy & lactation International studies indicate that there are widespread nutritional deficiencies across the developed world. Particular concern surrounds the minerals zinc, iron, calcium, magnesium and iodine, and the vitamins folate, B6, beta-carotene, A and C. Micronutrient deficiencies adversely affect pregnancy outcomes, impair child development and increase the risk of infectious and chronic, degenerative disease. Multivitamin and mineral supplementation has been shown to reduce the risk of low birth weight, infant morbidity and mortality. A sevenfold reduction in risk of very low birth weight has been demonstrated with supplementation from the 1st trimester.  Periconceptional multivitamin use (from 3 months prior through to 3 months of pregnancy) has been associated with a 25% reduced risk of cardiac defects in the offspring. Elderly Multivitamin and mineral supplementation in the elderly has been shown to decrease marginal or subclinical deficiency status and improve micronutrients to levels associated with immunocompetance and reduced risk for several chronic diseases. A large proportion of the elderly also do not meet the current RDA’s for a range of nutrients.

A survey of 686 elderly people found that the percentage of subjects who consumed less than two thirds of the RDA for various nutrients were as follows: B6 70%, folate 65%, vitamin D 60%, zinc 50%, calcium 31%, magnesium 25%, B12 25% and vitamin C 6%.   More recent studies indicate that more than 60% of older adults are vitamin D, E, folate and calcium deficient  and a high proportion of elderly people may have deficiencies of riboflavin, B6 and iron, despite apparently adequate dietary intakes. These percentages are worrying considering the strong evidence for the prevention of degenerative diseases, cancer, cardiovascular disease and cataracts by the antioxidant vitamins A, C, E and carotenoids, that immune function is associated with B6, Zn and vitamin C and E status, B6, folate and B12 are important for reducing homocysteine levels, and vitamin D, calcium and magnesium are essential for musculoskeletal functioning in osteoporosis and joint disease. Zinc and selenium deficiency risk increases with age, correlating with declining health in the elderly. Levels may be a useful index that may represent an early sign of disease.

High physical activity Exercise training is known to increase free radical production potentially leading to muscle injury. Athletes can use ten times the amount of oxygen during activity, so the oxidative stress on their body is immense. Vitamins C and E are well known antioxidants that may prevent muscle cell damage. A pilot study has found that vitamin C and E supplementation in soccer players may reduce lipid peroxidation and muscle damage during high intensity efforts (p<0.05).   For best results consider a flavonoids and vitamin C combination powder. Studies have shown that antioxidants should never be used in isolation and specific antioxidants including vitamins A, C and E, selenium, lycopene and lipoic acid are best prescribed in combination. Because exercise stresses metabolic pathways that depend on thiamine, riboflavin, and vitamin B6, the requirements for these vitamins may be increased in athletes and active individuals. Theoretically, exercise could increase the need for these micronutrients in several ways: through decreased absorption of the nutrients; by increased turnover, metabolism, or loss of the nutrients; through biochemical adaptation as a result of training that increases nutrient needs; by an increase in mitochondrial enzymes that require the nutrients; or through an increased need for the nutrients for tissue maintenance and repair. Exercise appears to decrease nutrient status even further in active individuals with pre-existing marginal vitamin intakes or marginal body stores. Chronic disease and convalescence Four of the ten leading causes of death (heart disease, cancer, stroke and diabetes), accounting for approximately two thirds of all deaths, have their pathology rooted in dietary problems.

In a Medical Journal of Australia report it was acknowledged that marginal deficiencies are more widespread than previously appreciated and that genetic factors and conditioning agents contribute to a number of trace element deficiencies in apparently w
ell nourished communities. These agents could include states of stress, ill health and pollution exposure. In a recent review on vitamins for chronic disease prevention it was concluded that inadequate intake has been linked to chronic diseases, including coronary heart disease, cancer and osteoporosis. Considering the enormous impact of these conditions on society, it has been estimated that huge cost savings could be made with some simple multi-nutrient supplementation. Findings from a large study indicate that use of multivitamin supplements may aid in the primary prevention of myocardial infarction (MI). The results are based on data from a case-control study of 45–70 year olds residing in Sweden, a country in which consumption of fruits and vegetables is relatively low and foods are not fortified with folic acid. After adjustment for major cardiovascular risk factors, the Odds Ratio of myocardial infarction comparing regular users of supplements with nonusers was 0.79 for men and 0.66 for women. An odds ratio of 1 would have indicated that MI was equally likely in both groups (users versus non-users). This association was not modified by such healthy lifestyle habits as consumption of fruits and vegetables, intake of dietary fibre, smoking habits and level of physical activity, although never smoking appeared to outweigh the association in women.

The study shows that use of low dose multivitamin supplements is associated with a substantially lower risk of nonfatal myocardial infarction. In a post hoc analysis of a randomised, double-blind, placebo-controlled study, multivitamin use was shown to be associated with lower C-reactive protein levels. C-reactive protein is a plasma protein and its levels rise dramatically during inflammatory processes occurring in the body. Patients with elevated levels of C-reactive protein are at an increased risk for diabetes, hypertension and cardiovascular disease. The study analysed the effects of the supplementation in 87 patients who did not have an inflammatory condition at baseline; and who were not hospitalized, taking antibiotics, smoking, or starting statin therapy during the study. C-reactive protein and plasma vitamin levels were measured at baseline and 6 months. At 6 months, C-reactive protein levels were significantly lower in the multivitamin group than in the placebo group (P= 0.005). The reduction in C-reactive protein levels was most evident in patients who had elevated at baseline. Of the six vitamins measured (C, E, B6, B12, folate, and beta carotene), only vitamin B6 ( P= 0.003) and vitamin C (P= 0.02) were inversely associated with C-reactive protein level. Compromised immunity Moderate deficiencies of nutrients, especially Zn, Fe, Se, vitamin A, B6, C and E, have been associated with poor immune function and supplementation has been shown to improve immune response.

Human intervention studies have found that important immune responses, such as increased lymphocyte proliferation and NK cell activity, improve when vitamin C, E or beta-carotene are consumed in amounts greater than the RDA. A large African study has found that multivitamin supplements delay the progression of HIV disease and provide an effective, low-cost means of delaying the initiation of antiretroviral therapy in HIV-infected women. 1078 pregnant women infected with HIV participated in a double-blind, placebo-controlled trial in Dar es Salaam, Tanzania, to examine the effects of daily supplements of vitamin A (vitamin A and beta carotene), multivitamins (vitamins B, C, and E), or both on progression of HIV disease, using survival models. Of 271 women who received multivitamins, 67 had progression to World Health Organization stage 4 disease or died as compared with 83 of 267 women who received placebo (24.7 percent vs. 31.1 percent; relative risk, 0.71; 95 percent confidence interval, 0.51 to 0.98; P=0.04). Multivitamin usage was also associated with reductions in the relative risk of death related to the acquired immunodeficiency syndrome (P=0.09), progression to WHO stage 4 (P=0.02), or progression to stage 3 or higher (P=0.003). Multivitamins also resulted in significantly higher CD4+ and CD8+ cell counts and significantly lower viral loads. The effects of receiving vitamin A alone were smaller and for the most part not significantly different from those produced by placebo.

 

References 1.

Troppmann L, Gray-Donald K, Johns T. Journal of the American Dietetic Association. 2002;102(6):818-825 2. Kennedy DO, Jackson PA,  Elliott JM et a. An evaluation of the cognitive and mood effects of administration with a multivitamin and mineral supplement for 12 weeks in schoolchildren Appetite 2008;50( 2-3):561 3. Butterworth CE. Effect of folate on cervical cancer- synergism among risk factors Annals NY Acad Sci 1997; 293-99 4. Zimmerman MB., Shane B. Supplemental folic acid. Am J Clin Nutr 1993;58:127-8 5. Combs GF. Food system-based approaches to improving micronutrient nutrition: the case for selenium. Biofactors 2000;12(1-4):39-43 6. Scholl TO et al. Prenatal multivitamin and mineral supplements reduce preterm delivery, low birth weight, infant morbidity and mortality Am J Epidemiol 1997;146:134-41 7. Occurrence of Congenital Heart Defects in Relation to Maternal Multivitamin Use – Botto LD, Mulinare J, Erickson JD. Am J Epidemiology 2000;151(9):878-884 8. Wood RJ et al. Mineral requirements of elderly people. Am J Clin Nutr 1995;62:493-505 9. de Jong N et al. Nutrient-dense foods and exercise in frail elderly: effects of B vitamins, homocysteine, methymalonic acid and neurological functioning. Am J Clin Nutr 2001;73(2):338-46 10. McKay DL et al. The effects of a multivitamin/mineral supplement on micronutrient status, antioxidant capacity and cytokine production in healthy older adults consuming a fortified diet. J Am Coll Nutr 2000;19(5):613-21 11. Tucker K. Micronutrient status and aging. Nutr Rev 1995;53(9):S9-15 12. Foote JA et al. Older adults need guidance to meet nutritional recommendations. J Am Coll Nutr 2000;19(5):628-40 13. Madigan SM et al. Riboflavin and B6 intakes and status and biochemical response to 14. Savarino L et al. Serum concentrations of zinc and selenium in elderly people: results in healthy nonagenarians/centenarians. Exp Gerontol 2001;36(2):327-39 15. Zoppi CC, Hohl R, Silva FC, Lazarim FL, Antunes Neto JMF, Stancanneli M and Macedo DV. Vitamin C and E Supplementation Effects in Professional Soccer Players Under Regular Training Journal of the International Society of Sports Nutrition. 3(2): 37-44, 2006. Available http://www.jissn.com/content/3/2/37. Accessed 02/09/2008 16. Manore MM.Effect of physical activity on thiamine, riboflavin, and vitamin B-6 requirements.m J Clin Nutr. 2000 Aug;72(2 Suppl):598S-606S 17. Percival M. The importance of optimal nutrition. Clin Nutr Ins 1997;5(3):1-6 18. Fairfield KM, Fletcher RH. Vitamins for Chronic Disease Prevention in Adults. JAMA 2002;287:3116-3126 19. Holmquist C, Larsson S, Wolk A, de Faire U.Multivitamin supplements are inversely associated with risk of myocardial infarction in men and women–Stockholm Heart Epidemiology Program (SHEEP). J Nutr. 2003 Aug;133(8):2650-4. 20. Church TS, Earnest CP, Wood KA, Kampert JB. Reduction of C-reactive protein levels through use of a multivitamin. Am J Med. 2003 Dec 15;115(9):702-7 21. Chandra RK. Nutrition and immunology: from the clinic to cellular biology and back again. Proc Nutr Soc 1999;58(3):681-3 22. Kelley DS, Bendich A. Essential nutrients and immunologic functions. Am J Clin Nutr 1996;63:994S-996S 23. Schroecksnadel K., Zangerle R., Fuchs D., Fawzi W. W., Msamanga G. I., Hunter D. J. Multivitamin Supplements and HIV Disease Progression N Engl J Med 2004; 351:1353-1354, Sep 23, 2004

 

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