Vitamins: Who needs them?
Each week a nutritionist from the University of Maryland Medical Center will provide a guest post on healthy eating. Have questions or ideas for future topics? Email firstname.lastname@example.org. This week, Amanda Tauber weighs in on vitamins.
Minerals, vitamins and supplements are a huge market in the United States. With nearly 50 percent of all Americans regularly taking a vitamin each day, it is a business worth over $3 billion, according to the General Conference Nutrition Council. A vitamin is defined as "any of a group of organic substances essential in small quantities for normal metabolism, found in minute amounts in natural foodstuffs or sometimes produced synthetically; deficiencies of vitamins produce specific disorders." But what if you get enough nutrients from the food you eat? Do you still need to take a vitamin?
For a person who eats a well-balanced diet, a multi-vitamin may not be necessary since you are receiving all of your nutrients from your food. However, the average American diet is high in protein and fat sources, but tends to be lower in fruit and vegetable sources and thus has overall lower nutritional quality since many key nutrients are found in fruits and vegetables. Other instances where a multi-vitamin may be necessary are during pregnancy, in someone who has chronic poor appetite leading to decreased food consumption, and/or when certain food groups are restricted or eliminated.
Vitamins A, C, E are key antioxidants that our body relies on to fight off illness and infection. Liver is the most common source of vitamin A, followed by sweet potatoes, carrots and mangoes. Although not a problem in the United States, vitamin A deficiency is the world's leading cause of blindness in children. According the World Health Organization, deficiencies in this nutrient “increase the risk of disease and death from severe infections” and for pregnant women can cause night blindness and increased maternal mortality.
Vitamin C is another important antioxidant found mostly in fruits and vegetables. People who smoke tend to be at an increased risk of being vitamin C deficient since the free radicals from cigarette smoke deplete vitamin C, so these individuals may want to either eat more food sources of the nutrient or take a vitamin C supplement. Also, your body only uses what vitamin C it needs to function with excess nutrient being excreted from the body Some good sources of vitamin C include citrus fruits, strawberries, tomatoes, broccoli and green peppers.
Vitamin E deficiency is rare deficiency. Good food sources are nuts, vegetable oil and green leafy veggies.
Vitamin D has gotten a lot of publicity lately, since many Americans tend to be deficient. Vitamin D is synthesized by the sun's rays hitting our skin, but during the winter months when we're bundled up, how much exposure does our skin get? Vitamin D also has very few food sources, such as fatty fish, fortified milk and egg yolk. The Recommended Daily Allowance for vitamin D is 600 IU/day for adults and 800 IU/day for seniors older than 70. Individuals with kidney concerns may need additional vitamin D as seen fit by their doctors. Some multi-vitamins may not contain the total recommended amount for vitamin D, so extra supplementation may not be a bad idea.
Other nutrients commonly found in a standard multi-vitamin are iron, folic acid and calcium. Iron is important for oxygen transport throughout the body and is found mostly in chicken liver, oysters and beef. Iron supplementation is especially important in pregnant women, menstruating women and individuals on dialysis. Folic acid or folate is a complex-B vitamin that our body uses to create new cells and is needed during periods of rapid cell division (pregnancy and infancy). Due to its importance for prevention of birth defects like spina bifida and other neural tube defects, folic acid has been added to many breakfast cereals. Pregnant and lactating women should strive to make sure they eat enough food sources of folic acid or supplement their diet.
Calcium is important for overall bone health, and deficiencies throughout life can lead to issues like osteoporosis. Milk and dairy products are great sources, so supplementation may be needed only if enough of these products are not adequately consumed.
Although Americans can be known for eating large amounts of food, the types of foods that we choose to eat may not be full of nutrients are body needs to function properly. Some important nutrients to pay attention to are vitamin C for smokers, vitamin D for those of us not getting a lot of sun, and folic acid and iron especially for pregnant women. As with any new health regimen, be sure to talk to your doctor since some nutrients may interfere with certain drugs. Remember, eating a well-balanced diet can also help you achieve results of having an adequately nourished body.