At the 8,436 turkey farms in the United States, America’s favorite native bird is incredibly susceptible to disease, illness and natural toxins. Coulombe has found that studying the extreme susceptibility of turkeys to feed-borne toxins make them an excellent experimental model of ways to reduce human cancer by dietary means through a process known as “chemoprevention.”
Coulombe is researching a class of food antioxidants that has been shown to protect turkeys from food-borne dietary toxins and carcinogens. If this additive protects people as well as it does turkeys, it could be used as a safe way to fight cancer.
“It takes a lot of research to get to the final answer. If you can find things along the way that will help humans or other forms of life, it is very rewarding.” — Roger Coulombe, Department of Animal Dairy & Veterinary Science
“Fellow scientists were at first incredulous of using turkeys as a cancer model, but there is an increasing acceptance of it, now that we have shown their usefulness in these studies.” said Coulombe. “We’ve received good support from granting agencies because our research has the dual benefit of helping the poultry industry and being valuable in human cancer research.”
Although Coulombe is looking at many antioxidants, one he is focusing on is butylated hydroxytoluene (BHT). Chemically, BHT is an antioxidant used as a food additive that prevents reactions that make oils rancid, thus keeping food fresher for longer. BHT is on the FDA’s list of chemicals that are “generally regarded as safe” in food. In addition to prolonging food’s shelf life, Coulombe has found that food containing BHT reverses the effects of aflatoxin poisoning in turkeys.
“Aflatoxin stems from mold in feed grains and is unavoidable in turkey production,” said Coulombe.
Coulombe found that turkeys’ are overly effective at “bioactivating” or making the toxins more dangerous through enzyme action, but they are extremely ineffective at altering the toxins into a form that can be excreted. Aflatoxin causes liver damage and poor weight-gain in turkeys, symptoms which BHT can counteract.
Not only does this research benefit the quality of farm-bred turkeys by preventing illnesses and death (see sidebar), but it also could help in human health. Although less of a danger to humans, aflatoxin-tainted peanuts, corn, and milk can cause illness. BHT could do the same thing for human aflatoxin poisoning as for turkeys.
Coulombe’s research, though, may be taken several steps further, from one type of food poisoning to cancer chemoprevention. The biggest threat to humans from chronic aflatoxin exposure is liver cancer. Coulombe and his students discovered that BHT inhibits aflatoxin bioactiviation, thus protecting animals, and potentially people.
Some of the enzyme that activate aflatoxin in people are quite similar to those that trigger aflatoxin in turkeys. Turkeys are hypersensitive to chemicals, which make them a good model for people who are fighting cancer.
Some of these enzymes in people are quite similar to those that trigger aflatoxin in turkeys and other birds. Turkeys are hypersensitive to chemicals, which make them a good model for people who are fighting cancer.
BHT may indeed reduce the incidence of cancer, but, more importantly, it serves as a “proof of concept” for the benefits of an antioxidant-rich diet in preventing cancer.
“Thirty percent of people will develop cancer during their lifetime,” said Coulombe. “The National Cancer Institute has stated that besides tobacco smoke, the single biggest contributor to cancer is diet and lifestyle, rather than genetics.”
Looking at naturally occurring compounds in food is called cancer chemoprevention because these compounds help decrease the incidence of cancer and improve human health. Foods that fall under this category are brussel sprouts, broccoli and cabbage. Coulombe says these foods boost protective enzymes by working with antioxidants added in people’s food.
“This message is one that we’ve been hearing for years,” said Coulombe. “If we eat less of certain things such as charbroiled steak and more fruits and vegetables and other foods that are rich in cancer chemopreventatives, we will have a greater chance of a long, healthy life.”
Coulombe said that people already know some of the things that he is finding through his research; they only need to start listening to the evidence.
Coulombe is working to get the word out to encourage people to change their eating habits. Society as a whole benefits from improved health.
How far this research will go, Coulombe is not sure. Research is always ongoing, he said.
“Healthy science is a dialectic process, where researchers must always be willing to change their hypotheses to fit with new data or with shifting scientific consensus,” said Coulombe.
“It takes a lot of research to get to the final answer,” said Coulombe. “If you can find things along the way that will help humans or other forms of life, it is very rewarding.”