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Mead acid

Mead acid
IUPAC name (5Z,8Z,11Z)-Eicosa-5,8,11-trienoic acid
CAS number 20590-32-3
PubChem 5312531
Molecular formula C20H34O2
Molar mass 306.48276
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Mead acid is an omega-9 fatty acid, first characterized by James F. Mead.[1] Mead acid is the only polyunsaturated fatty acid that the body can make de novum. Its elevated presence in the blood is an indication of essential fatty acid deficiency.



Chemically, Mead acid is a carboxylic acid with a 20-carbon chain and three methylene-interrupted cis double bonds. The first double bond is located at the ninth carbon from the omega end. In physiological literature, it is given the name 20:3(n-9). In the presence of lipoxygenase, Mead acid can form various hydroxy products (HETE).[2]


Humans and other mammals require essential fatty acids (EFA). During dietary EFA insufficiency—especially arachidonic acid deficiency—the body will make Mead acid by the elongation and desaturation of oleic acid.[3] [4] [5] Mead acid thus serves as an indicator of EFA deficiency. One study examined patients with intestinal fat malabsorption and suspected EFA deficiency. They were found to have blood-levels of Mead acid 1263% higher than reference subjects.[6]

Alternative views

The biologist Ray Peat suggests that the term essential fatty acid is a misnomer and that the human body can make eicosanoid-equivalents from Mead acid.[7] This view is disputed.[1]


  1. ^ a b Mary Enig (Spring, 2005). "A Reply to Ray Peat on Essential Fatty Acid Deficiency". Wise Traditions in Food, Farming and the Healing Arts. Retrieved on 2007-10-22.
  2. ^ Cyberlipid Center. PROSTAGLANDINS AND RELATED COMPOUNDS. Retrieved on 2007-10-24.
  3. ^ Phinney, SD, RS Odin, SB Johnson and RT Holman (1990). Reduced arachidonate in serum phospholipids and cholesteryl esters associated with vegetarian diets in humans. Retrieved on February 11, 2006. (reference is to 20:3n–9)
  4. ^ Lipomics. Mead acid. Retrieved on February 14, 2006.
  5. ^ Gerard Hornstra (September 2007). "Essential Polyunsaturated Fatty Acids and Early Human Development". Fats of Life Newsletter. Retrieved on 2007-10-23.
  6. ^ EN Siguel, KM Chee, JX Gong and EJ Schaefer (1987). "Criteria for essential fatty acid deficiency in plasma as assessed by capillary column gas-liquid chromatography". Clinical Chemistry 33: 1869-1873. Retrieved on 2007-10-24.
  7. ^ Peat, Ray (2006). Aspirin, brain, and cancer. Retrieved on 2007-10-22.

See also

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Mead_acid". A list of authors is available in Wikipedia.
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