PABA is the shortened name for para-aminobenzoic acid that is often thought of as only an ingredient used in sunscreens, while it is in actual fact a nutritional ingredient as well. Since it is a moiety of PGA, a form of folic acid, some health professionals do not consider it a vitamin, but only a B-complex factor.

Para-aminobenzoic acid (PABA), a component of pteroylglutamate, was once considered a vitamin and named vitamin B-x because it serves as a provitamin for some bacteria. Later studies in humans demonstrated that it does not have vitamin activity because humans lack the ability to synthesize folate from PABA. This biochemical is very useful in other ways and has been extensively utilized as a sunscreen in topical lotions to protect the skin from harmful ultraviolet radiation upon exposure to the sun. It is also effective in the treatment of vitiligo, a condition that causes discoloration of the skin.

PABA is used to improve the protein used in the body. It relates to red blood cell formation, as well as assists in the manufacture of folic acid in the intestines. Para-aminobenzoic acid is used in sunscreen preparations since it can help protect the skin against ultra-violet radiation. It has been linked to hair growth as well as reversing the graying of hair, but these results are disappointing. People suffering from vitiligo, over-pigmentation of skin, or without pigment in some spots, have reported an improvement of the skin after more PABA was ingested. PABA also assists with breaking down of protein, the formation of red blood cells and maintaining intestinal flora.

When PABA is in short supply fatigue, irritability, nervousness and depression might manifest itself, as well as constipation. Weeping eczema has also been noted in people with PABA deficiency, as well as patchy areas on the skin.

When higher than factor (SPF) 8 sunscreens are used, the manufacture of vitamin D in the body may be reduced. Nausea, skin rashes and vomiting might be indicative of PABA taken in excess. Excessive levels of PABA are stored in the body and may cause liver damage.

Long term antibiotic use may require more PABA from the body, but take note of PABA affecting the ability of sulfa drugs. Although not documented in medical terms, some women having problems becoming pregnant claim conceiving after increasing PABA in their diet.

PABA is found in liver, kidney, brewer's yeast, molasses, whole grains, mushrooms and spinach, and can be made by intestinal bacteria.