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


CONCLUSIONS
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.
Patenaude
A
A
[1] Cell Biology Laboratory, Canadian Centre for Agri-food Research in Health and Medicine (CCARM), St Boniface Hospital Research Centre [2] Department of Physiology, Faculties of Medicine and Pharmacy, University of Manitoba, Winnipeg, MB, Canada.
Rodriguez-Leyva
D
D
Edel
A L
AL
Dibrov
E
E
Dupasquier
C M C
CM
Austria
J A
JA
Richard
M N
MN
Chahine
M N
MN
Malcolmson
L J
LJ
Pierce
G N
GN
D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001682:Biological Availability; D004032:Diet; D004041:Dietary Fats / Q000493:pharmacokinetics*; D004311:Double-Blind Method; D015118:Eicosapentaenoic Acid / Q000097:blood*; D019597:Flax; D006801:Humans; D007408:Intestinal Absorption; D008875:Middle Aged; D028321:Plant Preparations / Q000737:chemistry / Q000493:pharmacokinetics*; D012639:Seeds; D014280:Triglycerides / Q000097:blood; D055815:Young Adult; D017962:alpha-Linolenic Acid / Q000097:blood / Q000493:pharmacokinetics*
D004041:Dietary Fats; D028321:Plant Preparations; D014280:Triglycerides; D017962:alpha-Linolenic Acid; D015118:Eicosapentaenoic Acid