PABA

PABA is also known as Paraaminobenzoic acid.

What does PABA do?

PABA is the abbreviation for paraaminobenzoic acid, a compound that is an essential nutrient for microorganisms and some animals, but has not yet been shown to be essential for people. PABA is loosely considered by some to be a member of the vitamin B-complex, though its actions differ widely from other B vitamins. PABA has been reported to enhance the effects of cortisone. It may also prevent or even reverse accumulation of abnormal fibrous tissue.

An isolated trial published in 1942 reported that twelve of sixteen infertile women were able to become pregnant after supplementing with 100 mg of PABA taken four times per day for three to seven months. The effect of PABA on fertility has not been studied in modern research.

Researchers have attempted to discover whether large amounts of PABA would be helpful in various connective tissue disorders. Although uncontrolled studies have reported that PABA (12 grams per day) was helpful to people with scleroderma, a placebo-controlled trial found PABA supplements did not lead to improvement.

Older published reports of uncontrolled investigations suggest that PABA may be helpful in a variety of conditions, including dermatomyositis, Peyronie’s disease (accumulation of abnormal fibrous tissue in the penis), pemphigus (a severe blistering disease) and vitiligo (a disorder in which patches of skin lose their pigmentation). However, PABA was reported to cause vitiligo in one report.

Older preliminary reports found that PABA darkened gray hair in a minority of elderly (but not younger) individuals. In these trials between 200 and 600 mg of PABA was taken per day for several months, in some cases accompanied by other B vitamins. At least one study failed to show any effect of PABA on darkening gray hair. Therefore, the evidence supporting the use of PABA as a way to return gray hair to its original color remains very weak.

Where is PABA found?

PABA is found in grains and foods of animal origin.

Who is likely to be deficient?

Deficiencies of PABA have not been described in humans, and most nutritionists do not consider it an essential nutrient.

How much PABA is usually taken?

Small amounts of PABA are present in some B-complex vitamins and multi-vitamin formulas. The amount of PABA used for the conditions described above ranges from 300 mg per day and up to 12 grams per day for autoimmune, connective tissue, or skin disorders. Anyone taking more than 400 mg of PABA per day should consult a nutritionally oriented physician.

Are there any side effects or interactions?

No serious side effects have been reported with 300–400 mg per day. Larger amounts (such as 8 grams per day or more) may cause low blood sugar, rash, fever, and (on rare occasions) liver damage. One report exists of vitiligo appearing after ingestion of large amounts of PABA, and use of amounts over 20 grams per day in small children has resulted in deaths.