Whole flaxseeds but not sunflower seeds in rye bread reduce apparent digestibility of fat in healthy volunteers.
OBJECTIVE
The aim of this study was to measure the apparent digestibility of fat and the transit time upon addition of whole sunflower seeds (SU) or flaxseeds (FL) to rye breads consumed as part of a whole diet.


METHODS
In a randomized crossover study, gross intake and faecal excretion of fat and energy were measured in 11 young healthy men aged 24.6+/-2.7 years. During each 7 days intervention periods, the subjects received a basal diet plus 300 g of one of four rye breads: (1) rye bread; (2) rye bread with SU; (3) rye bread with FL; (4) low extraction rate rye bread with SU and FL. Fat binding properties of rye breads (1) and (3) were determined by in vitro digestion.


RESULTS
Addition of whole SU or FL to breads increased daily gross intake of fat and energy (P<0.001). The amounts of apparently digested fat (g/day) and energy were lowered when subjects consumed the SU or FL rye bread (P<0.001). The effect on energy digestibility of FL was more pronounced than that of SU. The in vitro fat digestibility of rye breads and whole diets show fat-binding properties of FL when compared to the rye bread diet (P<0.05).


CONCLUSIONS
Enrichment of bread with whole FL does not appear to result in increased fat and energy intake when added to breads, but the results rather indicate an impairment of nutrient utilization.
Kristensen
M
M
Department of Human Nutrition/Centre for Advanced Food Studies, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark.
Damgaard
T W
TW
Sørensen
A D
AD
Raben
A
A
Lindeløv
T S
TS
Thomsen
A D
AD
Bjergegaard
C
C
Sørensen
H
H
Astrup
A
A
Tetens
I
I
D001939:Bread / Q000032:analysis; D018592:Cross-Over Studies; D004041:Dietary Fats / Q000008:administration & dosage / Q000378:metabolism*; D004063:Digestion; D002149:Energy Intake / Q000502:physiology*; D005243:Feces / Q000737:chemistry; D019597:Flax / Q000378:metabolism*; D005772:Gastrointestinal Transit / Q000502:physiology*; D006368:Helianthus; D006801:Humans; D008297:Male; D009765:Obesity / Q000517:prevention & control; D019518:Postprandial Period; D012434:Secale; D012639:Seeds; D055815:Young Adult
D004041:Dietary Fats