Olestra post-marketing surveillance study

Nutrition Research Newsletter, April, 2006

Olestra is a nonabsorbent, noncaloric fat substitute that has the properties of fat and is stable at temperatures used for baking and frying. In 1996 the Food and Drug Administration approved the use of this new fat substitute as an ingredient in the manufacture of snacks such as potato chips, corn chips, extruded snacks, and crackers. However, the FDA approval called for active postmarketing surveillance because preapproval studies showed that olestra may lower circulating concentrations of fat-soluble nutrients such as vitamins and carotenoids. Active surveillance rigorously examines the association of an exposure on a prespecified health or health-related outcome. Olestra was the first food ingredient to be subject to active postmarketing surveillance in the United States. Therefore, the objective of the Olestra Post-Marketing Surveillance Study was to examine whether customary consumption of olestra-containing snacks was associated with changes in serum fat-soluble vitamin and carotenoids concentrations among free-living persons I geographically and ethnically distinct US cities.

Adults (n = 2535) and their children aged 12 years to 17 years (n = 272) in Baltimore, Minneapolis, and San Diego attended clinic visits during which data were collected on diet, snack consumption, lifestyle, and anthropometric indexes. Nutrient intake was assessed with a validated 122-itern FFQ plus a 16-item savory snack questionnaire. Blood samples were drawn to measure carotenoids and the fat-soluble vitamins (A, D, E, and K). Data and blood samples were collected both before and after the nationwide introduction of olestra.

The mean daily olestra consumption among both adults and adolescents was approximately 0.75 g/day and those in the top decile consumed about two full servings per week, which suggests that use was very occasional at the population level. Compared with no intake, the top two tertiles of olestra use in adults were associated with circulating carotenoids concentration that were modestly but significantly lower. There were no significant associations of olestra with any serum nutrients among adolescents.

This active postmarketing surveillance study of a food additive suggests that small decreases in serum fat-soluble nutrients are attributable to olestra use. Although health outcomes were not measured here, it is unlikely that these small changes in nutrient measures would adversely affect health. The findings support the 2003 FDA ruling that olestra-containing snacks would no longer be required to include a label statement informing consumers that olestra may interfere with the absorption of fat-soluble nutrients such as vitamins and carotenoids nor that vitamins A, D, E, and K have been added to the products.

Marian L Neuhouser, Cheryl L Rock, Alan R Kristal, et al. Olestra is associated with slight reductions in serum carotenoids but does not markedly influence serum fat-soluble vitamin concentrations. Am J Clin Nutr ; 83: 624--631 (March 2006) [Address reprint requests to ML Neuhouser, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, M4-B402, PO Box 19024, Seattle, WA 98109-1024. E-mail: mneuhous@fhcrc.org]