Encyclopedia of Behavioral Medicine

Living Edition
| Editors: Marc Gellman

Fatty Acids, Free

  • Manjunath HarlapurEmail author
  • Daichi Shimbo
Living reference work entry
DOI: https://doi.org/10.1007/978-1-4614-6439-6_1261-2



Free fatty acids are unesterified, long-chain carboxylic acids. After esterification, fatty acids are found in the complex molecules like triacylglycerols. Usually, low levels of free fatty acids are seen in all tissues, but the substantial increase in the plasma is seen during fasting state. Free fatty acids are transported by albumin. Free fatty acids are oxidized mainly in the liver and muscle cells to provide energy. Fatty acids are also structural components of membrane lipids such as glycolipids and phospholipids. Fatty acids are also the precursor of prostaglandins. After esterification, fatty acids are stored as triacylglycerol in the adipose tissue, and this serves as a major reservoir of energy during fasting.

Fatty acids are called as “unsaturated” if they have at least one double bond in their chemical structure and “saturated” if they have none. Humans can only produce few unsaturated fatty acids in the body, and remaining fatty acids are obtained from the dietary intake, and these are called essential fatty acids. Two important essential fatty acids are linolenic and linoleic acids.

Omega numbering system is used for unsaturated fatty acids, and it depicts the position of double bond relative to the end of chain. Dietary intake of omega-3 fatty acids (e.g., linolenic acid) in the diet is associated with a reduced risk of cardiovascular disease events.


References and Further Reading

  1. Harvey, R. A., & Ferrier, D. R. (2008). Chapter 16: Lippincott’s illustrated reviews: Biochemistry (Lippincott’s illustrated reviews series) (4th ed., pp. 181–200). Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins.Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Center of Behavioral Cardiovascular Health, Division of General MedicineColumbia UniversityNew YorkUSA
  2. 2.Center for Behavioral Cardiovascular HealthColumbia UniversityNew YorkUSA

Section editors and affiliations

  • Linda C. Baumann
    • 1
  1. 1.School of NursingUniversity of Wisconsin-MadisonMadisonUSA