Long-chain omega-3 fatty acids and cancer: any cause for concern?

Curr Opin Clin Nutr Metab Care. 2018 Mar;21(2):83-89. doi: 10.1097/MCO.0000000000000439.

Abstract

Purpose of review: Recently, concerns have been raised with regard to the recommended doses of marine long-chain omega-3 polyunsaturated fatty acids (LC-omega-3 PUFAs) especially in relation to cancer risk and treatment. There is urgent need to clarify this point. This review considers the most recent evidence related to the potential risk of developing cancer with high LC-omega-3 PUFA intakes, and possible research strategies to better elucidate this matter.

Recent findings: The latest published recommendations have still highlighted the usefulness of an increased dietary intake of LC-omega-3 PUFAs for the prevention of some cardiovascular diseases. However, LC-omega-3 PUFAs have been related to the potential development and progression of cancer, and considerable debate exists on this issue.

Summary: The use of biomarkers reflecting the intake of LC-omega-3 PUFAs as cancer risk markers is discussed, as well as the possibility that the reported beneficial/deleterious effects may be confined to specific subpopulations on the basis of genetic, metabolic, and nutritional characteristics. Recent advances on new strategies for a safer intake of LC-omega-3 PUFAs will be considered, as their dietary sources may be contaminated by toxic/carcinogenic compounds. Potentially future directions in this important research area are also discussed.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Biomarkers, Tumor / blood
  • Diet
  • Dietary Supplements
  • Docosahexaenoic Acids / administration & dosage
  • Docosahexaenoic Acids / adverse effects
  • Docosahexaenoic Acids / blood
  • Eicosapentaenoic Acid / administration & dosage
  • Eicosapentaenoic Acid / adverse effects
  • Eicosapentaenoic Acid / blood
  • Fatty Acids, Omega-3 / administration & dosage
  • Fatty Acids, Omega-3 / adverse effects*
  • Fatty Acids, Omega-3 / blood
  • Humans
  • Neoplasms / blood*
  • Neoplasms / etiology
  • Risk Factors
  • alpha-Linolenic Acid / administration & dosage
  • alpha-Linolenic Acid / adverse effects
  • alpha-Linolenic Acid / blood

Substances

  • Biomarkers, Tumor
  • Fatty Acids, Omega-3
  • alpha-Linolenic Acid
  • Docosahexaenoic Acids
  • Eicosapentaenoic Acid