This is a three-part series focusing on the role vitamin and mineral supplements can play in supplementing essential vitamins and minerals Americans may not be getting from diet alone.
Part 1 of this series described the debate over the role vitamin and mineral supplements (VMS) may play in reducing the risks for various chronic diseases and how many health care professionals and consumers may have lost sight of the main function of vitamins and minerals as essential nutrients. Here in Part 2, we examine the basis for the Dietary Reference Intakes (DRIs), specific functions of the “gap” nutrients and the possible health consequences of insufficient intakes.
In the past, the recommended nutrient intakes from the Institute of Medicine (IOM) [the Recommended Dietary Allowances (RDA) in the United States and Recommended Nutrient Intakes (RNI) values in Canada] focused primarily on preventing nutritional deficiencies. In 1994, the scope changed and went beyond just reducing the incidence of diseases of nutritional deficiency to helping individuals optimize their health, prevent disease, and avoid consuming too much of a nutrient. [1] These new nutrient intake recommendations are called Dietary Reference Intakes, or DRIs, which include: [1]
- Estimated Average Requirements (EARs), the average intake level estimated to meet the requirements of half of the healthy individuals in a group (based on life stage and gender)
- Recommended Dietary Allowances (RDAs), the average intake level sufficient to meet the requirements of nearly all (97-98 percent) of healthy individuals in a group
- Adequate Intakes (AIs), the recommended average intake level based on approximations or estimates of intake by a group or groups of healthy people and that are assumed to be adequate; used when an RDA has not been determined
- Tolerable Upper Intake Levels (ULs), the highest average daily nutrient intake likely to pose no risk of adverse effects to almost all individuals in the general population
An analysis of 2007-2010 data from the National Health and Nutrition Examination Survey (NHANES) of more than 16,000 Americans 4 or more years of age showed that up to 90% obtained less than the EAR for one or more vitamins and minerals from foods alone (i.e., did not take vitamin or mineral supplements) (See Figure). [2]
Additionally, while less than 10% of the overall U.S. population has nutrition deficiencies, the prevalence of deficiencies varies considerably by age, gender, or race/ethnicity and is as high as nearly one third of certain population groups. The following are several examples from the Center for Disease Control’s (CDC) Second National Report on Biochemical Indicators of Diet and Nutrition: [3]
A Deep-dive Into Specialty Pharma
A specialty drug is a class of prescription medications used to treat complex, chronic or rare medical conditions. Although this classification was originally intended to define the treatment of rare, also termed “orphan” diseases, affecting fewer than 200,000 people in the US, more recently, specialty drugs have emerged as the cornerstone of treatment for chronic and complex diseases such as cancer, autoimmune conditions, diabetes, hepatitis C, and HIV/AIDS.
- 30 million Americans (10.5%) have a vitamin B6 deficiency, with higher rates among non-Hispanic blacks (15.7%) and those 60 years and older (16%). [3] Vitamin B6 deficiency is associated with microcytic anemia, dermatitis (scaling on the lips and cracks at the corners of the mouth) and glossitis (swollen tongue), depression and confusion, and weakened immune function. [4], [5] Individuals with borderline vitamin B6 concentrations or mild deficiency might have no deficiency signs or symptoms for months or even years.
- 23 million Americans (8.1%) have severe vitamin D deficiency.* Non-Hispanic black (31.1%) and Mexican-American (11.3%) people were more likely to be vitamin D deficient compared to non-Hispanic white people (3.6%). [3] Few foods contain vitamin D and people get it from exposure to sunlight. However, its synthesis is reduced in darkly pigmented skin and with sunscreen use. The potential effects of vitamin D deficiency include rickets (children), osteomalacia and osteoporosis (adults), muscle weakness and compromised immune function. [6]
- 5 million women age 12-49 years (9.5% of that group) have low body iron status, with higher rates among Mexican Americans (13.2%) and non-Hispanic blacks (16.2%). Iron is needed for the formation of hemoglobin. Iron deficiency is linked to reduced physical capacity, poor pregnancy outcomes, and can progress to anemia if not treated. [3]
- Approximately one-third of pregnant women in the United States are marginally iodine deficient. [7] Iodine is an essential component of thyroid hormones which play a key role in normal growth and development. These hormones regulate critical enzymes and metabolic processes. Iodine deficiency disorders include mental retardation, hypothyroidism and varying degrees of growth and developmental abnormalities in children. [1]
Research has proven that vitamins and minerals play a critical role in supporting health, including major discoveries of their roles in preventing rare, but serious vitamin deficiency diseases in the U.S.
The functions of other nutrients low in many Americans’ diets (Figure) are shown in the Table below.
* The scientific/medical literature is inconsistent in defining vitamin D deficiency. Here “severe vitamin D deficiency” is defined as a 25-hydroxyvitamin D serum level < 30 nmol/L; the cut-off used by the Institute of Medicine (IOM) as the criterion for increased risk for rickets. However, the IOM also defined < 50 nmol/L as “insufficient” to maintain bone health, and some scientific reports interpret values below this cut-off as ‘deficient.’ Based on a 50 nmol/L cutoff, the CDC report shows that nearly 90 million Americans (31.7%) have vitamin D deficiency/insufficiency, with higher rates in non-Hispanic blacks (70.6%) and Mexican-Americans (44.2%). [3]
Additional research is needed to determine the long-term health impact of low vitamin and mineral intakes. On the other hand, the nutritional functions and required intake levels of vitamins and minerals are well established, and there is no evidence that supplements providing approximately 100% of the recommended levels of vitamins and minerals are harmful. Given the evidence, VMS can be recommended as a reasonable way, in conjunction with improving diet quality, to help many Americans get adequate amounts of vitamins and minerals.
The Campaign for Essential Nutrients is comprised of Bayer HealthCare LLC, DSM Nutritional Products, PHARMAVITE LLC. and Pfizer Inc.
References
- Otten JJ, Hellwig JP, Meyers LD, eds. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press; 2006. Available at http://www.nal.usda.gov/fnic/DRI/Essential_Guide/DRIEssentialGuideNutReq.pdf. Accessed December 22, 2015.
- Wallace TC, McBurney M, Fulgoni VL 3rd. Multivitamin/mineral supplement contribution to micronutrient intakes in the United States, 2007-2010. J Am Coll Nutr. 2014;33(2):94-102.
- Centers for Disease Control. Second National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population. Available at http://www.cdc.gov/nutritionreport/pdf/4Page_%202nd%20Nutrition%20Report_508_032912.pdf. Accessed November 30, 2015.
- Ross CA, Caballero B, Cousins RJ, Tucker KL, Ziegler TR, eds. Modern Nutrition in Health and Disease. 11th Baltimore, MD: Lippincott Williams & Wilkins; 2014.
- Oregon State University. Linus Pauling Institute. Micronutrient Information Center. Available at: http://lpi.oregonstate.edu/mic. Accessed November 3, 2015.
- Holick MF. Vitamin D Deficiency. New England Journal of Medicine 357;3:266-281, 2007.
- American Academy of Pediatrics Council on Environmental Health, Rogan WJ, Paulson JA, et al. Policy Statement: Iodine deficiency, pollutant chemicals, and the thyroid: new information on an old problem. Pediatrics. 2014 Jun;133(6):1163-6.
