Good Fats versus Bad Fats: A Comparison of Fatty Acids in the Promotion of Insulin Resistance, Inflammation, and Obesity

Mo Med. Jul-Aug 2017;114(4):303-307.


Recently, debate has erupted in both the scientific community and throughout the lay public around whether a low-fat or low-carbohydrate diet is better for weight loss. In other words, is it better to cut fat or cut carbohydrate for weight loss. However, going beyond this debate (fat versus carbohydrate), are questions around whether certain fatty acids are worse for promoting insulin resistance, inflammation, and obesity. The overall evidence in the literature suggests that medium-chain saturated fats (such as lauric acid, found in coconut oil) and monounsaturated fat (oleic acid, found in olive oil) are less likely to promote insulin resistance, inflammation, and fat storage compared to long-chain saturated fatty acids (such as stearic acid found in large quantities in butter, but particularly palmitic acid found in palm oil) especially when consumed on top of a diet moderate in refined carbohydrates. Compared to long-chain saturated fats, lauric acid and oleic acid have an increased fatty acid oxidation rate, are more likely to be burned for energy and less likely to be stored in adipose tissue, and thus promote increased energy expenditure. Omega-6 polyunsaturated fatty acids (PUFAs), such as linoleic acid, as found in vegetable oils may contribute to obesity, whereas omega-3 PUFA may be protective. Importantly, both olive oil as part of a Mediterranean diet, and omega-3 from fish and fish oil have been proven to reduce risk of cardiovascular (CV) events.

Publication types

  • Comparative Study

MeSH terms

  • Adipose Tissue / cytology
  • Adipose Tissue / metabolism
  • Cardiovascular Diseases / epidemiology
  • Cardiovascular Diseases / prevention & control
  • Diet / methods
  • Diet / statistics & numerical data
  • Energy Metabolism / physiology
  • Fatty Acids / adverse effects
  • Fatty Acids / metabolism*
  • Fatty Acids, Omega-3 / adverse effects
  • Fatty Acids, Omega-3 / metabolism
  • Female
  • Fish Oils / administration & dosage
  • Fish Oils / adverse effects
  • Humans
  • Inflammation / metabolism*
  • Insulin Resistance / physiology*
  • Lauric Acids / adverse effects
  • Lauric Acids / metabolism
  • Linoleic Acid / adverse effects
  • Linoleic Acid / metabolism
  • Lipid Metabolism / physiology
  • Male
  • Obesity / metabolism*
  • Oleic Acid / adverse effects
  • Oleic Acid / metabolism
  • Olive Oil / administration & dosage
  • Olive Oil / adverse effects
  • Stearic Acids / adverse effects
  • Stearic Acids / metabolism


  • Fatty Acids
  • Fatty Acids, Omega-3
  • Fish Oils
  • Lauric Acids
  • Olive Oil
  • Stearic Acids
  • lauric acid
  • Oleic Acid
  • stearic acid
  • Linoleic Acid