Para-aminobenzoic acid, commonly known as PABA, is a food or nutritional supplement that is available from both natural and synthetic sources. It is not considered an essential nutrient, so there is no documentation for a nutritional deficiency. There is, however, documentation of the various ways in which it contributes to the maintenance of good health.
A person's skin can easily suffer damage when exposed to ultraviolet radiation such as the light that reaches Earth from the sun. PABA has been proven to help to shield the skin against ultraviolet radiation when applied topically as a chemical-based sunscreen would be. Sunburns and eczema are among the other skin disorders that show great improvement or that are eliminated when para-aminobenzoic acid is used topically. Its effectiveness in the treatment of skin disorders and other health problems when taken internally is disputed, but some people have noticed improvement in a variety of conditions after taking para-aminobenzoic acid as a nutritional supplement.
Among the other health conditions that para-aminobenzoic acid is believed to treat, cure or improve are arthritis, unexplained hair loss, anemia, vitiligo and headaches. These benefits of taking the supplements are considered unproved. Para-aminobenzoic acid is even said to help to restore graying or white hair to the color it was in the person's youth. Folic acid, a vitamin that is an essential nutrient, can be produced by intestinal bacteria. Such stimulation, however, is produced by para-aminobenzoic acid, so it does play an important part in essential nutrition. Folic acid, in turn, aids in the production of yet another essential nutrient, vitamin B5, also known as pantothenic acid.
Toxicity has been noted in cases of overdose of para-aminobenzoic acid. Jaundice, a liver disease evidenced by vomiting and yellow skin and eyes, could be present after taking a toxic dose of this supplement. Nausea and diarrhea are adverse reactions or side effects that have been noted in individuals taking the supplements, but these symptoms usually disappear if their use is discontinued immediately.
The interaction of this supplement with other substances should be considered by anyone planning to take this supplement. Interactions can be adverse or beneficial. For example, PABA helps to increase the effectiveness of vitamin C and the B-complex vitamins. Adverse interactions include interference with some antibiotics and sulfa drugs. It is best to obtain para-aminobenzoic acid naturally from food sources such as brown rice, yogurt, molasses and heirloom grain products, such as those made with spelt.