Synthetic Preservatives

These are widely used synthetic preservatives:

BHA—Butylated Hydroxyanisole

BHT— Butylated Hydroxytoluene

TBHQ — Tertiary Butylhydroquinone

Preservatives are used primarily to prevent fats from becoming rancid, allowing food to have a longer “shelf-life.” Most preservatives are not believed to be a health hazard, but the above three petroleum-based preservatives have been found to trigger behavior and health problems.

Studies on these chemicals are disturbing. As early as 1974, a study by Stokes and Scudder reported that when pregnant mice were fed BHA and BHT, it affected the brain chemistry of their offspring, reducing their cholinesterase and serotonin to half the normal levels. They reported , “The affected mice weighed less, slept less and fought more than normal controls.”

These preservatives continue to enjoy GRAS (generally recognized as safe) status despite evidence that they are:

Toxic to various cells and organs<1>

Tumor promoters<2>

Weaken the immune system<3>

Impact the nervous system and behavior<4>

Have a negative effect on sperm and/or egg production<5>

Damage reproduction and development<6>

BHA has been listed as a cancer-causing chemical since the 6th Annual Report on Carcinogens in 1991. It has been listed as a carcinogen in every report since then. In the year 2011, the 12th Report on Carcinogens stated — again — that BHA is “reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.”<7>


Most additives have never been studied in combination with each other.


These preservatives are often used in the oils used in food products and are generally not included in the ingredient list.

1. Zoccarato 1987; Thompson 1988; Kahl 1983, 1993; Siman 1996; Gudz 1997; Stolze 1999; Safer 1999; Yu 2000; Groten 2000

2. Kahl 1984; Parke 1992; Kahl 1993; Bauer 2001; Sasaki 2002

3. Tryphonas 1999

4. Stokes 1974; Tanaka 1993

5. Takami 1999

6. Meyer 1980; Vorhees 1981, McFarlane 1997

7. 12th Report on Carcinogens, National Toxicology Program


This information has been reprinted from the Feingold Bluebook, Behavior, Learning & Health: the Dietary Connection.

Read about the Feingold Diet here.