A person who has a niacin deficiency may develop symptoms that affect his skin, mucous membranes, gastrointestinal system, and even his central nervous system. Those who develop skin symptoms because of a niacin deficiency may develop rashes and lesions. Often, the mouth is affected, and people may develop reddened, painful, ulcerated areas in the mouth as well as an increase in saliva production. A person with a niacin deficiency may also develop abdominal discomfort, constipation, and even bloody diarrhea. Women may also experience pain and redness in the vaginal area. Severe cases may result in psychological changes and dementia as well.
When a person has a niacin deficiency, he often develops signs that affect his skin. For example, he may develop lesions and rashes at pressure points on his body as well as in places that are exposed to the sun. When the face is affected, a butterfly-like rash may form or the person may develop a necklace-like ring around his neck. Lesions may also form in a glove-like pattern on the patient's hands or a boot-like pattern on his feet and legs. The lesions that develop when a person has a deficiency of niacin often form on both sides of the patient’s body.
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Signs of deficiency that affect the mucous membranes are often found inside a person's mouth. They may also, however, affect a person’s vagina and urethra, which is the tube that carries urine to the outside of a person’s body. A person with this deficiency may develop swelling of the tongue, redness, and pain inside the mouth. Mouth ulcers may develop as well, and many patients with signs of this deficiency experience increased salivation.
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A person who is deficient in niacin may also develop symptoms that affect his pharynx, which is a section of the throat, and his esophagus, which passes food from the pharynx to the stomach. He may experience burning in both of these areas. In many cases, abdominal swelling and pain is present as well. Constipation, diarrhea, nausea, and vomiting may also develop as signs of a deficiency in niacin.
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In some cases, central nervous system changes may develop as signs of niacin deficiency. For example, a person may develop psychosis with this condition. Dementia may be a sign of deficiency as well. In some cases, a patient with a niacin deficiency may even experience an altered consciousness.
It is important to note that a niacin deficiency is less likely to develop in people who live in developed countries. This does not mean, however, that it cannot develop. For this reason, a person who develops symptoms that seem to indicate a niacin deficiency should see his doctor for diagnosis and treatment. In most cases, people with this deficiency can be treated with diet supplementation.