By Mark A. Kelley, MD |2/15/18
Founder, HealthWeb Navigator
Vitamins and other over-the-counter supplements are extremely popular in the United States. In fact, it’s estimated that Americans spend $21 billion on these products every year—a few billion dollars more than NASA’s entire annual budget.
Over the last century, there has been extensive research to understand the importance of vitamins and minerals in maintaining good health. Essential vitamins and minerals are chemicals that our bodies cannot manufacture on their own. Usually they’re introduced to our bodies by the food we eat.
There are some great stories surrounding the discovery of certain vitamins and minerals. Three centuries ago, sailors on long voyages often became very ill, many of whom died. The cause was lack of vitamin C in their diet, a condition known as scurvy. To provide vitamin C, these sailors were given limes to eat on the voyage. Miraculously the condition disappeared.
Another example comes from the early twentieth century, when patients were mysteriously dying from anemia despite an adequate diet. Studies showed that they lacked a protein that is necessary to absorb vitamin B12. When the patients were given vitamin B12 by injection, their anemia vanished.
Over time medical science has learned much more about how vitamins and minerals keep us healthy. Yet even in this era of health supplements, the average person still wonders, “What should I be doing to maintain good health?”
Below, we’ll look at a few of the consensus recommendations for vitamin use based on clinical studies to date.
Are Vitamins and Supplements Necessary?
For a healthy person, a well-balanced diet will supply the necessary minerals and vitamins. A balanced diet should include fruits, grains, vegetables, protein, and some dairy products. These foods have the right nutrients that our bodies are designed to absorb to keep us healthy.
Folic acid supplement during pregnancy has been shown to reduce neural tube (spinal) defects in infants. This major advance may save many infants from a lifetime of disability.
Strict vegans may need vitamin supplements. A completely vegetarian diet may lack vitamins B12 and D, and the patient may require oral supplements to correct these deficiencies. The same approach applies to anyone on a poor or restricted diet.
Vitamin D may require some supplement. Vitamin D is necessary for bone growth and strength and comes from two sources. The first is from food, and the second from our skin, which produces vitamin D in response to sunlight. Low vitamin D levels can be seen in patients whose diets are poor or who rarely go out in the sun. For this reason, many experts advise oral vitamin D supplements for older patients who may be at risk for osteoporosis or bone fracture.
Multivitamins are safe, but usually aren’t necessary. Patients with poor diets or digestion may benefit from multivitamins or other supplements. However, for an average person, the consensus is that these products are unnecessary. Nonetheless, multivitamin doses are generally modest and likely won’t harm healthy patients who want to use them within the usual recommended doses.
Beware of high doses of certain vitamins. High doses of the following vitamins can cause lasting damage to your health:
• Vitamin A: Birth defects, osteoporosis, increased cardiac mortality
• Beta-Carotene: Lung cancer
• Vitamin C: Kidney stones
Based on current research, there is no evidence that supplemental vitamins or antioxidants prevent or improve the outcomes of cancer or cardiac disease.
Vitamin and mineral supplements can sometimes be helpful. But for those of us who take prescription medications, they can also cause dangerous interferences. This field is complex, and the science behind it is constantly evolving. Before taking any supplements, it is wise to consult your physician and discuss what is best for you.
An internist and pulmonologist, Dr. Kelley is a faculty member at Massachusetts General Hospital and Harvard Medical School.