In food and the body
Palmitoylethanolamide was first identified in 1957 in egg yolk, soybean and peanut oil. It was found in mammalian tissues in 1965.
Amounts measured in foods
The amounts are small. These figures are from Rankin and Fowler 2020.
- Soy lecithin: 950 micrograms per gram
- Roasted coffee: 7.2 micrograms per gram
- Black-eyed peas: 0.14 micrograms per gram
- Apples, lentils and potatoes: under 10 nanograms per gram of dry weight
- Human breast milk: about 0.1 to 3 nanomolar
For scale, published human trials used 300 to 1,200 milligrams a day. A gram of soy lecithin, the richest food listed, holds less than one milligram.
How the body makes it
- An enzyme moves a fatty acid onto a membrane fat called phosphatidylethanolamine. This forms an N-acylphosphatidylethanolamine, or NAPE.
- A second enzyme, NAPE-PLD, cuts the NAPE and releases palmitoylethanolamide.
There is at least one other route. Mice without NAPE-PLD still have about 60% of the normal level in the brain.
How the body clears it
Two enzymes, FAAH and NAAA, split it into palmitic acid and ethanolamine. Both are ordinary substances in the body. See Breakdown: FAAH and NAAA.