Effect of cow milk on food folate bioavailability in young women.
BACKGROUND
The findings of animal and human studies suggest that a certain component in milk enhances food folate bioavailability.


OBJECTIVE
The objective was to evaluate whether cow milk enhances the bioavailability of food folate in humans.


METHODS
Thirty-one young women were fed low-folate diets on a 4-d rotation with (n=17) or without (n=14) cow milk for 8 wk. Plasma and erythrocyte folate and plasma total homocysteine (tHcy) concentrations were monitored.


RESULTS
Plasma folate concentrations steadily declined in both the milk and the nonmilk groups; however, the declines were not significantly different between groups (P=0.09). In contrast, erythrocyte folate concentrations declined only in the nonmilk group and remained unchanged in the milk group; the difference between the 2 groups was significant (P=0.01). Plasma tHcy concentrations significantly increased in the nonmilk group and remained unchanged in the milk group; the difference between the 2 groups was significant (P=0.02).


CONCLUSIONS
The inclusion of cow milk in the diet enhanced the bioavailability of food folate as assessed by the changes in erythrocyte folate and plasma tHcy concentrations but not in plasma folate concentrations. The mechanisms of action by the components of cow milk remain to be investigated.
Picciano
Mary Frances
MF
Department of Nutrition, Pennsylvania State University, University Park, USA. piccianm@od.nih.gov
West
Sheila G
SG
Ruch
Amanda L
AL
Kris-Etherton
Penny M
PM
Zhao
Guixiang
G
Johnston
Kelley E
KE
Maddox
Deborah H
DH
Fishell
Valerie K
VK
Dirienzo
Douglas B
DB
Tamura
Tsunenobu
T
D000328:Adult; D000818:Animals; D001682:Biological Availability; D002417:Cattle; D004032:Diet; D004912:Erythrocytes / Q000737:chemistry*; D005260:Female; D005492:Folic Acid / Q000378:metabolism / Q000493:pharmacokinetics*; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007408:Intestinal Absorption; D008892:Milk / Q000737:chemistry / Q000378:metabolism
D006710:Homocysteine; D005492:Folic Acid