Your new reason to love vegetarian cuisine.
By Emily Main
January 3, 2014
Looking for an easy New Year's resolution? Eat less meat. You might just
stave off cancer, finds a new study in the journal Nutrients.
The author reviewed cancer rates in 157 countries and compared those with food
consumption patterns for those countries collected by the United Nation's Food
and Agriculture Organization. He also looked at other potential cancer risk
factors, including gross domestic product, life expectancy, lung cancer
incidence (an index for smoking) and latitude, a marker of vitamin D exposure.
His conclusions: If you want to stave off the widest variety of cancers, stop
smoking, eat fewer animal products and get more vitamin D. Countries with high
rates of animal product consumption--meat, dairy, eggs, and fish--also saw high
rates of 12 different types of cancer, including breast, kidney, liver, ovarian,
prostate, testicular and thyroid cancers. Low solar UVB exposure, a marker for
vitamin D absorption, was associated with six different types: bladder, brain,
kidney, lung, melanoma, and Hodgkin’s lymphoma. And lung cancer incidence rates
also correlated to 12 non-lung varieties of cancer.
Simply put, "eating a lot of animal products is not good for health," says
William Grant, PhD, author of the study and president of the Sunlight Health
Nutrition and Research Center, a nonprofit nutrition research institute.
"They're a very important risk factor for many types of cancer and that's not
that well recognized by most people."
There are a couple reasons he says that animal products might trigger cancer,
one of which is something known as insulin-like growth factor 1, or IGF-1. That
hormone exists in all animal products, even eggs and fish, and it causes
animals--and people--to grow. That's why, Grant says, in places like Asia, older
populations that were raised on a vegetable-heavy diet are generally shorter
than younger populations that have adopted a more animal-heavy Western diet. And
just as it makes people grow, IGF-1 makes tumors grow, too. (Fish contains
vitamin D and omega-3 fatty acids, which counteract some of the damage caused by
IGF-1, Grant says.)
It also seems that all animal products--organic or conventional--can raise your
levels of IGF-1, which is increased by artificial hormones given to non-organic
animals. Grant points to research conducted as far back as 1907 finding that
northern Europeans with meat-heavy diets were still suffering higher cancer
rates than Italians and Asians and their vegetarian-leaning cuisines. That was
long before the introduction of artificial growth hormones.
Another factor that could contribute to animal products' cancer-promoting
effects is iron, excess amounts of which can cause oxidative stress that creates
cancerous free radical compounds in the body.
Interestingly, Grand adds that eating a healthy, vegetable-heavy diet can
even counteract some of the damage caused by not getting enough vitamin D. His
analysis revealed that in countries with low levels of UVB exposure, healthy
diets were protective against at least 11 different types of cancer. At the same
time, in countries close to the equator, a bad diet couldn't overcome the
benefits of a lot of vitamin D.
"In the United States, you probably a get similar effect of a lot of vitamin D
by eating less meat," he says.
Grant isn't advocating for a total vegan diet. "I eat meat, fish, eggs, and
dairy, but I'm trying to eat more vegetables, more grains, more legumes," he
says. "Just cut down on animal products." In some of the world's healthiest
societies, animal products contribute a mere 12 to 15 percent of total calorie