Depression, irritability, mental confusion and even indigestion can be signs that you are low on vitamin B-3.
The B vitamins are what helps the body convert carbohydrates into energy, and to metabolize fats and protein. Since the B vitamins are water-soluble, our bodies do not store what we don't immediately use and we must continuously replenish the supply.
The best foods for supplying B-3 are pork, poultry, beets, brewer's yeast, sunflower seeds, peanuts and dried beans, plus oily fish like salmon that also supply omega-3. Breads and cereals are often fortified with niacin, a form of B-3, ans niacin helps improve circulation and reduce cholesterol levels.