By Dr Julia lee, For The Guardian

erica@nasguard.com

In a nutshell, "No". Supplements, while often beneficial, cannot take the place of nutrient-rich fruits, vegetables, and whole grains. Dietary supplements are meant to . . . well, supplement the diet. They are not meant to be food substitutes. Whole foods offer three main benefits over dietary supplements:

Greater nutrition - Whole foods provide a combination of nutrients. For example, a fresh orange provides not only vitamin C but also calcium, beta carotene, and other healthy nutrients that may not even have been identified yet. The combination of nutrients found in nature are absorbed better, more efficient and more beneficial to the body than vitamin C in a pill form. Fibre - Whole foods provide fibre which help prevent certain diseases and improve bowel health.

Protective substances - Whole foods contain natural substances called "phytochemicals" that help protect you from certain diseases and antioxidants that slow down tissue damage.

The key lifestyle message is - eating a diet rich in fruits, vegetables, and whole grains is one of the best ways to improve your overall health.

For some people who cannot or don't eat enough, including those on restrictive diets, dietary supplements can provide vitamins and minerals their diets lack. For example, a regular multivitamin-mineral supplement containing vitamin B-12 would be recommended for a vegan (a vegetarian who does not eat any dairy).

Women in child-bearing years should consider taking a daily multivitamin supplement to ensure adequate folic acid (400 micrograms) to prevent certain neural tube birth defects in the event of pregnancy.

A multivitamin with iron can help match iron lost in menstruation.

For bone health, a combined approach of exercise, vitamin D (which can be made by the body with sun exposure) and adequate calcium is needed. Calcium supplement pills can be very helpful in providing the daily need for calcium.

A daily multivitamin can be helpful for persons who may have inadequate nutrition due to chewing and swallowing problems, depression, chronic illness or medication use, and poor digestion. These problems are often seen in the elderly.

If you decide to take a supplement, avoid those that provide "megadoses". It is also not necessary to choose expensive so-called "natural" vitamin or those with added herbs, enzymes, or amino acids. Higher costs of particular brands don't necessarily mean higher quality. Be aware that some herbs can interact negatively with certain medications. A standard multivitamin-mineral that provides 100% of the Daily Value (DV) of all vitamins and minerals (except calcium, which would make the pill too large) is recommended.

For specific help with diet and nutrition, consult with a nutrition professional such as a registered dietitian.

Julia Lee, RD, MS

Registered Dietitian

Doctors Hospital