Bioavailability of alpha-linolenic acid from flaxseed diets as a function of the age of the subject

Eur J Clin Nutr. 2009 Sep;63(9):1123-9. doi: 10.1038/ejcn.2009.41. Epub 2009 Jul 8.


Background: Dietary flaxseed may have beneficial cardiovascular effects. An aged population has a higher incidence of cardiovascular disease, but they may react differently to flaxseed in the diet.

Objective: To investigate the response, over a period of 4 weeks, of subjects aged 18-29 or 45-69 years to a diet containing the same amount of alpha-linolenic acid (ALA) (6 g) introduced in the form of ground flaxseed (30 g) or flaxseed oil.

Results: All subjects who received flaxseed oil showed a significant increase in plasma ALA and eicosapentaenoic acid (EPA) concentrations over the course of this study. Subjects who received ground flaxseed in the 18-29-year-old group showed a statistically significant increase in their plasma ALA levels, and although there was a trend in the same direction for the 45-69-year-old subjects, this did not achieve statistical significance. The diets induced no major changes in platelet aggregation, plasma total cholesterol, low-density lipoprotein or high-density lipoprotein cholesterol levels in any of the groups. Younger subjects showed a decrease in triglyceride (TG) values compared with older subjects. There were no significant side effects that caused compliancy issues.

Conclusion: Subject age does not seem to be a major determining factor in influencing ALA absorption from a flaxseed-supplemented diet nor in the metabolism of ALA to EPA in the groups fed flaxseed oil. Concerns about side effects in older subjects administered a higher fiber load in a flaxseed-supplemented diet are not justified. However, younger but not older subjects showed a beneficial decrease in circulating TGs due to flaxseed supplementation.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aging / physiology*
  • Biological Availability
  • Diet
  • Dietary Fats / pharmacokinetics*
  • Double-Blind Method
  • Eicosapentaenoic Acid / blood*
  • Flax*
  • Humans
  • Intestinal Absorption*
  • Middle Aged
  • Plant Preparations / chemistry
  • Plant Preparations / pharmacokinetics*
  • Seeds
  • Triglycerides / blood
  • Young Adult
  • alpha-Linolenic Acid / blood
  • alpha-Linolenic Acid / pharmacokinetics*


  • Dietary Fats
  • Plant Preparations
  • Triglycerides
  • alpha-Linolenic Acid
  • Eicosapentaenoic Acid