No-Carb Diet May Curb Prostate Cancer
In Lab Tests on Mice, Prostate Tumors Grow Slower With No-Carbohydrate Diet
Nov. 13, 2007 -- Forgoing carbohydrates may slow the growth of
prostate cancer, according to preliminary lab tests in mice.
The researchers aren't making dietary recommendations for men. But they say
the topic deserves further study.
"This study showed that cutting carbohydrates may slow tumor growth, at
least in mice," Duke University urologist Stephen Freedland, MD, says in a
"If this is ultimately confirmed in human clinical trials, it has huge
implications for prostate cancer therapy through something that
all of us can control -- our diets," says Freedland, who plans to start
such trials next year.
Freedland's team split 75 mice into three groups:
- Low-fat diet: 12% fat, 16% protein, 72% carbohydrate
- Western diet: 40% fat, 16% protein, 44% carbohydrate
- No-carb diet: 84% fat, 16% protein, 0% carbohydrate
The no-carb diet was modeled on a special
diet sometimes given to prevent seizures in children with
epilepsy, Freedland's team notes.
After 24 days on the diets, the mice got an injection of human prostate
The mice on the no-carb diet outlived the mice on the Western diet. The
no-carb mice also had tumors that were a third smaller after 51 days than the
mice on the Western diet.
Tumor growth and survival were similar for the mice on the low-fat and
"One could argue that the [no-carb] diet provides no advantage and
future studies should focus on a low-fat diet," the researchers write in
today's online edition of The Prostate.
But they suggest that the no-carb diets may have other advantages, such as
weight loss and lower levels of a tumor-promoting chemical.
The study's limits include the fact that it only involved mice and its
relatively short time span.
Whether the findings apply to people -- and the long-term effects -- remain
to be seen.
As Freedland's team notes, the no-carb diet used in their study was very
high in fat, and high-fat diets have been linked to greater risk of prostate
heart disease, and other health problems.
The type of fat may make a difference. For instance, Freedland and
colleagues got different results in a past study that used corn oil as mice's
main source of fat rather than milk fat or lard.
Other researchers have shown that
intensive diet and lifestyle changes may slow prostate cancer without
requiring anyone to give up carbohydrates.