Many people take vitamins because of their supposed anti-aging properties, but it's a fact that you need to supplement your vitamins as you get older. The anti-oxidant properties of Vitamins C and E are documented and help to counteract cell deterioration.

Vitamin B12 is one of the vitamins that many older people can be lacking. B12 is one of the vitamins that our body produces by chemical actions inside our stomachs. Some people don't absorb B12 properly and need to get their vitamins supplemented. Over the age of 50, up to 30 percent of the population will have some problem with B12 absorption. Sometimes taking B12 vitamins by mouth can help. However, if the problem is that the stomach cannot absorb B12 vitamins, it may be necessary to get B12 shots, which introduces the vitamins directly into the bloodstream. Your doctor can do blood tests to check your B12 levels.

As we get older, our ability to produce vitamin D also declines. While sun exposure alone is enough to trigger adequate production of D vitamins in most people, by the time we reach age 70 our skin only produces one-quarter the D vitamins it did from the same amount of sun exposure when we were 25. Seniors who are housebound, who live in the northern parts of North America, or who cannot go outside without sunscreen are likely to need to get their D vitamins from supplements.

Certain medications can also interfere with the body's ability to use the vitamins we normally get from food. Be honest with your doctor about your diet and lifestyle and ask what supplementary vitamins you should be taking.