title: 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.
abstract: 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.
authors.affiliation: Department of Nutrition, University of North Carolina-Chapel Hill, Chapel Hill, NC 27599-7461, USA. boyd_switzer@unc.edu
authors.forename: Boyd R
authors.initials: BR
authors.lastname: Switzer
authors.forename: Jan R
authors.initials: JR
authors.lastname: Atwood
authors.forename: Aliza H
authors.initials: AH
authors.lastname: Stark
authors.forename: John W
authors.initials: JW
authors.lastname: Hatch
authors.forename: Rebecca
authors.initials: R
authors.lastname: Travis
authors.forename: Fred
authors.initials: F
authors.lastname: Ullrich
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Lyden
authors.forename: Xiumei
authors.initials: X
authors.lastname: Wu
authors.forename: Yulanda
authors.initials: Y
authors.lastname: Chiu
authors.forename: Jan L
authors.initials: JL
authors.lastname: Smith
mesh_terms: 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*
chemical_list: D004043:Dietary Fiber; D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids; D002784:Cholesterol; D012256:Riboflavin