Plasma carotenoid and vitamins a and e concentrations in older African American women after wheat bran supplementation: effects of age, body mass and smoking history.
OBJECTIVE
This study investigated the relationships of plasma vitamins A, E, and carotenoids with age, BMI and former/non-smoking history after adjusting for wheat bran supplementation.


METHODS
All 39 African American women in the church-based, volunteer sample, 40-70 years old, supplemented their daily diets for 5-6 wks. with 1/2 cup of a riboflavin-spiked wheat bran cereal.


RESULTS
Urinary riboflavin concentrations increased from 0.8 +/- 0.1 mg/day at baseline to 7.5 +/- 0.5 mg/day after supplementation, confirming the 99.2 +/- 10.5% self-reported adherence. Plasma nutrient concentrations did not change significantly with supplementation nor was never/former smoking history related to diet. Plasma retinol and serum cholesterol were significantly higher (p < 0.0002) in persons older than 55 years compared to younger adults. Plasma retinol (microg/dL) but not serum cholesterol was associated significantly with menopausal status and hormone replacement therapy (HRT; p = 0.05); progressive increases in retinol concentrations were found in the women after adjusting for pre/post supplementation: lowest in pre-menopause (47.7 +/- 4.8); intermediate concentrations in post-menopause on HRT (54.6 +/- 3.0); highest level in post-menopause without HRT (61.1 +/- 3.0). Similarly, a progressive increase was found in lipid-unadjusted alpha-tocopherol concentrations and menopausal status with or without HRT. Vitamin A and cholesterol intakes were not significantly different by age group. Plasma carotenoids were not significantly different by age or fiber supplementation, but alpha- and beta-carotene and beta-cryptoxanthin were significantly lower with BMI > or = 30. In contrast to carotenoids, both plasma levels of gamma-tocopherol and lipid-adjusted gamma-tocopherol were significantly higher with obesity compared to those with BMI < 30.


CONCLUSIONS
Plasma alpha- and beta-carotene and beta-cryptoxanthin were negatively associated with obesity, whereas gamma-tocopherol measures were consistently elevated with high BMI. The increase in age-associated plasma retinol in postmenopausal women was likely related to decreased estrogen concentrations in the African American women. Smoking history was not influential in this study.
Switzer
Boyd R
BR
Department of Nutrition, University of North Carolina-Chapel Hill, Chapel Hill, NC 27599-7461, USA. boyd_switzer@unc.edu
Atwood
Jan R
JR
Stark
Aliza H
AH
Hatch
John W
JW
Travis
Rebecca
R
Ullrich
Fred
F
Lyden
Elizabeth R
ER
Wu
Xiumei
X
Chiu
Yulanda
Y
Smith
Jan L
JL
D000328:Adult; D001741:Black or African American; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000097:blood; D015992:Body Mass Index; D002338:Carotenoids / Q000097:blood*; D002784:Cholesterol / Q000097:blood; D004043:Dietary Fiber / Q000008:administration & dosage*; D019587:Dietary Supplements; D005260:Female; D020249:Hormone Replacement Therapy; D006801:Humans; D008593:Menopause / Q000097:blood; D008875:Middle Aged; D012256:Riboflavin / Q000652:urine; D012907:Smoking / Q000097:blood*; D014801:Vitamin A / Q000097:blood*; D014810:Vitamin E / Q000097:blood*
D004043:Dietary Fiber; D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids; D002784:Cholesterol; D012256:Riboflavin