Site-specific concentrations of carotenoids in adipose tissue: relations with dietary and serum carotenoid concentrations in healthy adults.

BACKGROUND

Dietary carotenoids are related to a decreased risk of certain diseases. Serum and adipose tissue carotenoid concentrations are used as biomarkers of intake.

OBJECTIVES

The objectives of this study were to evaluate site-specific concentrations of carotenoids in adipose tissue and to examine relations between carotenoid concentrations in the diet, serum, and adipose tissue.

DESIGN

Healthy adults (12 women and 13 men) participated in this cross-sectional study. Dietary carotenoids over the past year were assessed with a food-frequency questionnaire. Serum and adipose tissue biopsy samples were collected from the abdomen, buttock, and inner thigh for the measurement of carotenoids by HPLC.

RESULTS

Many adipose carotenoids were inversely related to percentage body fat, although lycopene was the only carotenoid inversely correlated with all 3 sites. Most of the carotenoids were significantly higher in the abdominal adipose tissue than in the thigh (P < 0.05). Concentrations of alpha-carotene, beta-carotene, 5-cis-lycopene, and total carotenoids were significantly higher in the buttocks than in the thigh (P < 0.05). Concentrations of alpha-carotene, cis-lycopene, and lutein (with or without zeaxanthin) were significantly higher in the abdomen than in the buttocks (P < 0.05). Dietary intake was significantly correlated with serum concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, and total carotenoids. Carotenoid intake was significantly correlated with adipose tissue concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, cis-lycopene, and total carotenoids (P < 0.05) but varied by site. Of all the adipose tissue sites evaluated, the abdomen showed the strongest correlation with long-term dietary carotenoid intakes and with serum (indicator of short-term intake) for most carotenoids.

CONCLUSIONS

Body fat may influence the tissue distribution of carotenoids. Abdominal adipose tissue carotenoid concentrations may be a useful indicator of carotenoid status.