Pellagra is the old-fashioned name for sun damaged skin, with dermatitis and ulcers. It is usually associated with a deficiency in Vitamin B3 (niacin). A painful, swollen tongue, anxiety, depression, loss of appetite or diarrhoea may also occur.
An article in The New England Journal of Medicine (Damian, 2015) reported that the risk of developing skin cancers can be reduced by increasing intake of vitamin B3 (nicotinamide) in high risk patients.
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