Palmitic acid

Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is one of the most common saturated fatty acids found in animals and plants. As its name indicates, it is a major component of the oil from palm trees (palm oil and palm kernel oil). The word palmitic is from the French "palmitique", the pith of the palm tree. Butter, cheese, milk and meat also contain this fatty acid.

Palmitate is a term for the salts or esters of palmitic acid. The palmitate anion is the observed form of palmitic acid at physiological pH.

Biochemistry
Palmitic acid is the first fatty acid produced during lipogenesis (fatty acid synthesis) and from which longer fatty acids can be produced. Palmitate negatively feeds back on acetyl-CoA carboxylase (ACC) which is responsible for converting acetyl-ACP to malonyl-ACP on the growing acyl chain, thus preventing further palmitate generation.

Reduction of palmitic acid yields cetyl alcohol.

Uses
Palmitate is an antioxidant and a vitamin A compound added to low fat milk to replace the vitamin content lost through the removal of milk fat. Palmitate is attached to the alcohol form of vitamin A, retinol, in order to make vitamin A stable in milk.

Derivatives of palmitic acid were used in combination with naphtha during World War II to produce napalm (naphthenic and palmitic acids).

The WHO reports "convincing" evidence that dietary intake of palmitic acid increases risk of developing cardiovascular diseases. However, possibly less-disinterested studies have shown no ill effect, or even a favorable effect, of dietary consumption of palmitic acid on blood lipids and cardiovascular disease, so that the WHO finding may be deemed controversial. The controversy may be resolved by a study showing palmitic acid to have no hypercholesterolaemic effect if intake of linoleic acid was greater than 4.5% of energy, but that if the diet contained trans fatty acids, the health effects would be unfavorable (with an LDL cholesterol increase and HDL cholesterol decrease).