Niacin is also known as vitamin B3 and nicotinic acid. It is of the essential human nutrients.
All B vitamins help the body to convert food (carbohydrates) into fuel (glucose), which is used to produce energy. These B vitamins, often referred to as B complex vitamins, also help the body use fats and protein. B complex vitamins are needed for healthy skin, hair, eyes, and liver. They also help the nervous system function properly.
All the B vitamins are water-soluble, meaning that the body does not store them.
Not enough niacin in the diet can cause nausea, skin and mouth lesions, anemia, headaches, and tiredness. Chronic Niacin deficiency leads to a disease called pellagra. The lack of niacin may also be observed in pandemic deficiency disease which is caused by a lack of five crucial vitamins: niacin, vitamin C, thiamin, vitamin D and vitamin A, and is usually found in areas of widespread poverty and malnutrition.
You can meet all of your body's needs for Vitamin B3 through diet. It is rare for anyone in the developed world to have a B3 deficiency. alcoholism is the main cause of vitamin B3 deficiency.
Niacin deficiency is generally treated with a nutritionally balanced diet and niacin supplements. Niacin deficiency also causes burning in the mouth and a swollen, bright red tongue.
Very high doses of B3, available by prescription, have been studied to prevent or improve symptoms of the following conditions. However, at high doses niacin can be toxic. You should not take doses higher than the Recommended Daily Allowance except under your doctor's supervision. Researchers are trying to determine if inositol hexanicotinate has similar benefits without serious side effects, but so far results are preliminary.
Food sources
Niacin is found in variety of foods, including liver, chicken, beef, fish, cereal, peanuts and legumes, and is also synthesized from tryptophan, an essential amino acid found in most forms of protein.
Animal products:
liver, heart and kidney (9 – 15 mg niacin per 100 grams)
chicken, chicken breast (6.5 mg)
beef (5 – 6 mg)
fish: tuna, salmon, halibut (2.5 – 13 mg)
eggs (0.1 mg)venison (8.43 mg)
Fruits and vegetables:
avocados (1 mg niacin per 100 grams)
dates (2 mg)
tomatoes (0.7 mg)
leaf vegetables (0.3 - 0.4 mg)
broccoli (0.6 mg)
carrots (0.3 - 0.6 mg)
sweet potatoes (0.5 - 0.6 mg)asparagus (0.4 mg)
Seeds:
nuts (2 mg niacin per 100 grams)
whole grain products (4 - 29.5 mg)
legumes (0.4 – 16 mg)
saltbush seeds
Fungi:
mushrooms, shiitake mushrooms (3.5 – 4 mg niacin per 100 grams)
brewer's yeast (36 mg)
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