Zinc is a nutritionally essential mineral needed for catalytic, structural, and regulatory functions in the body.
The RDA (recommended daily allowance) for adult women and men is 8 mg a day and 11 mg a day of zinc, respectively.
Severe zinc deficiency is a rare, genetic or acquired condition. Dietary zinc deficiency, often called marginal zinc deficiency, is quite common in the developing world, affecting an estimated 2 billion people. Zinc deficiency can cause impaired growth and development in children, pregnancy complications, immune dysfunction, and increased susceptibility to infections. Long-term consumption of zinc in excess of the tolerable upper intake level of 40 mg a day for adults can result in copper deficiency.
Zinc bioavailability is relatively high in meat, eggs, and seafood. Zinc is less bioavailable from whole grains and legumes due to the inhibitory effects of phytic acid on absorption of the mineral.
Vitamin B3, Niacin, nicotinic acid, helps to convert food into energy and is essential for healthy skin, blood cells, brain, and nervous system. It is one of 8 B vitamins. It is water-soluble, which means it is not stored in the body. It has 2 other forms, niacinamide (nicotinamide) and inositol hexanicotinate, which have different effects.
Niacin occurs naturally in food and can also be made by your body from the amino acid tryptophan, with the help of B6.
It is rare for anyone in the developed world to have a Vitamin B3 deficiency; alcoholism is the main cause of it in the US.
Recommended daily amount: 14 - 16 mg.
Example sources: whole grains, mushrooms, peanuts and other legumes.