A daily multivitamin is a good nutrition insurance policy. Some extra vitamin D may add an extra health boost.

5 Quick Tips Getting the Right Vitamins

1. Eat a healthy diet. A multivitamin provides some insurance against deficiencies but is far less important for health than the healthy food patterns described on this website. Choose a diet rich in fruits, vegetables, whole grains, nuts and healthy oils, and low in red meat and unhealthy fats—let the Healthy Eating Pyramid and Healthy Eating Plate be your guides.

2. Choose a daily multivitamin. A daily multivitamin is an inexpensive nutrition insurance policy, and for most people, the benefits seem to outweigh the risks. Try to take one every day.

3. Think about D. In addition to its bone health benefits, there’s growing evidence that getting some extra vitamin D can help lower the risk of colon and breast cancer. Aim for getting 800 to 1,000 IU of vitamin D per day—this likely will require an extra vitamin D pill, in addition to your multivitamin. Many people may need 2,000 IU per day (or more) for adequate blood levels of vitamin D, particularly if they have darker skin, spend winters at higher latitudes (such as the northern U.S.), or spend little time in the sun. If you fall into one of these groups, which would include most of the U.S. population, taking 2,000 IU is reasonable and well within the safe range. As always, it’s a good idea to discuss use of supplements with your doctor, and he or she may want to order a vitamin D blood test. For more information, see the vitamin D section of The Nutrition Source.

4. Say no to “megas.” In general, avoid mega-dose vitamins and mega-fortified foods. Vitamin D is an exception, as many people need more than the Recommended Dietary Allowance (RDA). A standard multivitamin also has a day’s worth of folic acid, so you should avoid foods that have high amounts of folic acid added to them.

5. Avoid “super” supplements. Don’t be swayed by the wild health claims of the many health supplements advertised on TV and the Internet. If they sound too good to be true, you can be sure they are. Save your money for healthy food and a good vacation.

http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/vitamins/index.html