Niacin deficiency affects the skin, mucous membranes, gastrointestinal tract, and nervous system. You may experience mild symptoms such as angular cheilitis, loss of appetite, anxiety, and fatigue due to lack of cellular energy.

Pellagra, a skin disease known as niacin deficiency, causes inflammation such as redness and dryness of the face and hands and feet that are exposed to the sun. When it gets worse, gastrointestinal disorders, diarrhea, neurological disorders such as headaches, depression, and dementia will occur, and in the case of children, growth failure will occur. In Central and South America, the intake of foods containing niacin is low, and the staple food, corn, is low in tryptophan, so pellagra is still seen today.

Considering the current dietary habits in Japan, there is no need to worry about niacin deficiency, but in the case of alcoholics, niacin deficiency may occur. This is because if you don’t eat enough and drink a lot of alcohol, you will be deficient in niacin. Minor deficiencies such as decreased appetite, angular cheilitis, and anxiety may occur.

Excessive intake of niacin in your daily diet is unlikely to cause any health hazards. Ingesting large amounts of niacin can cause your skin to become inflamed, itchy, and sore. However, this is temporary and has no adverse health effects. If it gets worse, gastrointestinal symptoms such as vomiting, diarrhea, and constipation, and liver damage such as decreased liver function and fulminant hepatitis will occur.