These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Bioavailability of beta-carotene is lower in raw than in processed carrots and spinach in women.
    Author: Rock CL, Lovalvo JL, Emenhiser C, Ruffin MT, Flatt SW, Schwartz SJ.
    Journal: J Nutr; 1998 May; 128(5):913-6. PubMed ID: 9567003.
    Abstract:
    Populations at risk of vitamin A deficiency usually rely on dietary provitamin A carotenoids to meet vitamin A needs, yet bioavailability of these compounds is influenced by several factors as follows: location in the plant source, the presence of other influencing dietary components, and type and extent of processing. The purpose of this study was to examine the plasma beta-carotene response to raw vs. processed carrots and spinach. Subjects were eight healthy females aged 23-36 y who consumed approximately 9.3 mg beta-carotene daily from either raw or thermally processed and pureed vegetables in two 4-wk treatment periods in a crossover study. Plasma concentrations of total, all-trans-, and cis-beta-carotene and alpha-carotene were measured at base line and the end of each treatment period by using HPLC assays. Total and all-trans (but not cis) plasma beta-carotene concentrations were significantly greater than base-line concentrations in the processed feeding period (P < 0. 04) and tended to be greater in the raw feeding period (P = 0.08). Daily consumption of processed carrots and spinach over a 4-wk period produced an increase in plasma beta-carotene concentration that averaged three times that associated with consumption of the same amount of beta-carotene from these vegetables in the raw form (P = 0.09). Increased cis isomers provided in the processed vegetables did not result in significantly greater plasma cis-beta-carotene isomer concentrations. These results suggest that isomerization of beta-carotene by heat treatment does not negate the enhanced beta-carotene uptake associated with consuming commercially processed vegetables compared with raw vegetables.
    [Abstract] [Full Text] [Related] [New Search]