Vitamins - Why Do We Need Them? What Do They Do? How Do They Help?Share
Vitamins are fat-soluble or water-soluble organic compounds necessary for the healthy functioning of the body.
We are unable to make vitamins, therefore, we are required to get them from food or take them in an extracted form (1). Vitamins and minerals supply the body with the nutrients essential to promote normal cell growth.
There are 13 essential vitamins necessary for proper bodily functions like metabolism, as well as building bones, teeth, muscles, blood, and a number of tissues. Water-soluble vitamins are quickly eliminated from the body through urine, so we must consume them daily to replenish. These include B vitamins and vitamin C (2). Fat–soluble vitamins use the fats we consume to transport themselves throughout the body. Fat-soluble vitamins are also stored in fatty tissues in the body longer than water-soluble vitamins so daily consumption of some fat-soluble vitamins is not necessary like it is for water-soluble vitamins (3).
Vitamins help the body in a variety of ways. While we require them for overall optimal health, we more specifically need them for proper functioning of the cardiovascular system, bone health, immune function, and physical fitness. In terms of what vitamins specifically do for the body, this all depends on the vitamin. B2 or riboflavin, for example, aids in healthy skin, hair, and nail growth while aiding eyesight. Vitamin A or retinol also benefits eyesight while boosting immunity and promoting healthy appetite (4).
Vitamins A, C, and E are antioxidants that protect cells from being damaged. When we don't receive enough of these vitamins, we risk and increase in heart problems because the integrity of our blood cells can become compromised (5). Vitamin D plays an essential role in bone health because it promotes better absorption of calcium. Additionally, you can get vitamin D from sun exposure.
There are several vitamins crucial to proper immune function. A healthy immune system ensures that we are able to properly fight viral and bacterial infection, deal with inflammation and stress, effectively digest food, and heal. Vitamin A aids in skin repair while also building and fortifying mucus membranes (mouth lining, gut lining, etc.) (6). Without enough vitamin A, the immune system is unable to defend the body. Additionally, vitamin C is important in immunity because it synthesizes collagen. Wounds cannot fully heal without collagen. B vitamins like thiamin, riboflavin, and niacin are important for fueling the body during workouts. Vitamin C aids in the repairing of muscles and the building of new muscle tissue (7).
Although supplementation has become a popular method by which to obtain essential vitamins, the preferred method is still through diet and nutrition. According to the American Cancer Society, eating a variety of fruits and vegetables remains the best source of essential vitamins and minerals (8). The plant compounds and other nutrients found in fruits and vegetables add additional benefits - like phytonutrients and fiber, for example. Commercial produce in the United States has diminished nutritional value due to the overuse of inorganic nitrogen fertilizers, and other farming practices that leave the soil depleted (9). Food grown in nutrient deficient soil lacks the nutrients needed for optimal health. Research shows that the nutritional values of food have declined substantially over the last several decades due to mineral depletion of the soil (10). This makes organic practices the preferred method by which to replenish soil and increase nutritional value.
Consuming a variety of different foods helps to guarantee the body gets what it needs without having to supplement. Still, sometimes this can pose challenges, especially for those with food allergies. When taking supplements, be sure to choose high quality brands that are free from heavy metals because, like organic vs. non-organic food, not all supplements are created equal.
References:(1, 3) Fairfield, K. M., & Fletcher, R. H. (2002). Vitamins for chronic disease prevention in adults: scientific review. Jama, 287(23), 3116-3126.
(2) Kennedy, D. O., & Haskell, C. F. (2011). Vitamins and cognition. Drugs, 71(15), 1957-1971.
(4, 6) Fitzpatrick, T. B., Basset, G. J., Borel, P., Carrari, F., DellaPenna, D., Fraser, P. D., ... & Fernie, A. R. (2012). Vitamin deficiencies in humans: can plant science help?. The Plant Cell Online, 24(2), 395-414.
(5, 7) Guimaraes, R., Barros, L., Carvalho, A. M., Sousa, M. J., Morais, J. S., & Ferreira, I. C. (2009). Aromatic plants as a source of important phytochemicals: Vitamins, sugars and fatty acids in and Eucalyptus gunnii leaves. Industrial Crops and Products, 30(3), 427-430.
(8) Byers, T., Nestle, M., McTiernan, A., Doyle, C., Currie-Williams, A., Gansler, T., & Thun, M. (2002). American Cancer Society guidelines on nutrition and physical activity for cancer prevention: reducing the risk of cancer with healthy food choices and physical activity. CA: A Cancer Journal for Clinicians, 52(2), 92-119.
(9, 10) Brandt, K., & Molgaard, J. P. (2001). Organic agriculture: does it enhance or reduce the nutritional value of plant foods?. Journal of the Science of Food and Agriculture, 81(9), 924-931.