Article

Effect of dietary fiber intake on lipoprotein cholesterol levels independent of estradiol in healthy premenopausal women.

Epidemiology Branch, Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Rockville, Maryland, USA.
American journal of epidemiology (impact factor: 5.59). 01/2011; 173(2):145-56. DOI:10.1093/aje/kwq388
Source: PubMed

ABSTRACT High-fiber diets are associated with improved lipid profiles. However, pre- and postmenopausal women respond differently to fiber intake, suggesting that endogenous estradiol mediates the effect. The authors' objective was to determine the direct effect of fiber intake on lipoprotein cholesterol levels independent of estradiol among premenopausal women. The BioCycle Study, a prospective cohort study conducted at the State University of New York at Buffalo from 2005 to 2007, followed 259 healthy women for up to 2 complete menstrual cycles. Serum lipoprotein and hormone levels were measured at 16 visits timed using fertility monitors. Fiber intake was assessed by 8 24-hour recalls. Marginal structural models with inverse probability weights for both lipoprotein and estradiol levels were used to estimate controlled direct effects of the highest category of fiber intake (≥22 g/day vs. <22 g/day) while accounting for age, body mass index, total energy, vitamin E intake, physical activity, luteinizing hormone, follicle-stimulating hormone, and progesterone. Reductions were observed in total and low density lipoprotein cholesterol in women with higher fiber intakes. Direct effects were greater than total effects. These analyses suggested that estradiol mediates at least part of the association between fiber and cholesterol among premenopausal women. More research is needed to elucidate the biologic mechanisms driving these associations.

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Keywords

16 visits timed
 
2 complete menstrual cycles
 
259 healthy women
 
authors' objective
 
BioCycle Study
 
body mass index
 
endogenous estradiol mediates
 
fertility monitors
 
Fiber intake
 
High-fiber diets
 
higher fiber intakes
 
inverse probability weights
 
lipoprotein cholesterol levels independent
 
low density lipoprotein cholesterol
 
Marginal structural models
 
New York
 
postmenopausal women
 
premenopausal women
 
prospective cohort study
 
vitamin E intake