Olestra vs Butylated Hydroxyanisole: which is worse?

What is Olestra?

Olestra (brand name Olean) is a synthetic fat substitute made from sucrose and fatty acids. Unlike regular fats, olestra is not absorbed by the digestive system — it passes through the body unchanged, providing zero calories while mimicking fat's texture and taste in food. It was developed by Procter & Gamble and FDA-approved in 1996.

What is Butylated Hydroxyanisole?

Butylated hydroxyanisole (BHA) is a synthetic phenolic antioxidant preservative derived from petroleum. It is a mixture of two isomeric compounds (2-BHA and 3-BHA). BHA prevents fats and oils from oxidizing (going rancid), extending shelf life. Its chemical formula is C11H16O2.

Documented risks

Olestra: Olestra caused significant gastrointestinal side effects that were prominently noted on mandatory warning labels: 'This Product Contains Olestra. Olestra may cause abdominal cramping and loose stools. Olestra inhibits the absorption of some vitamins and other nutrients. Vitamins A, D, E, and K have been added.' Reported gastrointestinal effects included diarrhea, abdominal cramping, oily anal leakage ('anal leakage' or 'rectal leakage'), and fatty stools. These effects were often embarrassing and uncomfortable. Multiple consumer complaints documented GI distress from Olean chips. Beyond GI effects, olestra significantly inhibits the absorption of fat-soluble vitamins (A, D, E, K) and fat-soluble carotenoids (lycopene, lutein, beta-carotene). Since fat-soluble vitamins require fat for absorption, and olestra passes through without being absorbed, it 'captures' these vitamins and carries them out of the body. Studies found olestra consumption reduced serum carotenoid levels, prompting Frito-Lay to fortify olestra products with fat-soluble vitamins to compensate. The FDA removed the mandatory GI warning requirement in 2003 after Frito-Lay argued the warning was overstated, though olestra's use had already declined dramatically due to consumer avoidance.

Butylated Hydroxyanisole: BHA is classified by the International Agency for Research on Cancer (IARC) as Group 2B (possible human carcinogen) based on studies showing it causes papillomas and squamous cell carcinomas of the forestomach in rats, hamsters, and mice at high doses. A 1983 NTP bioassay confirmed these findings. The National Toxicology Program lists BHA as 'reasonably anticipated to be a human carcinogen' in its Report on Carcinogens. The forestomach is an anatomical structure found in rodents but not humans, creating some uncertainty about direct extrapolation. EFSA's 2012 re-evaluation (EFSA Journal 2012;10(10):2588) concluded that BHA may have endocrine-disrupting potential based on animal data showing interactions with estrogen receptors and androgenic hormone pathways. EFSA found the ADI of 1 mg/kg body weight but noted concerns about endocrine effects. Japan banned BHA for use in foods containing fats and oils, consistent with its generally precautionary approach to synthetic food preservatives. In cosmetics, the EU Scientific Committee on Consumer Safety (SCCS) has assessed BHA and found potential endocrine-disrupting effects at dermal exposure levels. EWG rates BHA as high-concern in Skin Deep cosmetics database. The antioxidant paradox applies: while BHA prevents lipid oxidation in foods, it may paradoxically act as a pro-oxidant in certain biological contexts at certain doses.