Your Newspaper - Your Health - Quality over Quantity

Posted on: September 9, 2009

Quality over Quantity

What you eat could have as much impact on breast cancer risk as how much you eat, a new study says.

By Perry Gattegno
CTW Features

Intermittent rather than permanent calorie restriction may be more effective in lowering breast cancer risk, according to research done at the University of Minnesota’s Hormel Institute, Austin, Minn.

Researchers used two calorie restriction methods, chronic and intermittent, on two groups of 10-week-old mice to determine how often the mice would develop would develop mammary tumors. In mice that ate whatever they wanted, 71 percent developed mammary tumors. The chronically restricted mice developed tumors 35 percent of the time, while only nine percent of the intermittently restricted mice developed tumors.

These results shocked the experimenters since the accepted theory for breast tumor development states that tumors develop proportionally to the degree of calorie prevention. The researchers also expected some tumors may have developed on the intermittent plan since growth hormones would be secreted in response to refeeding.

The results were published in Cancer Prevention Research, a journal of the American Association for Cancer Research, Philadelphia.

The findings suggest that eating well – fruits, vegetables, lean proteins and healthful carbohydrates – is more important than calorie counting. Diets based around calorie restriction often result in weight loss followed by weight gain when a dieter stops following the plan.

“Humans frequently regain lost weight, discouraging the application of calorie restriction protocols for disease prevention,” says Dr. Margot P. Cleary, a professor at the Hormel Institute. “We hope these studies will identify biomarkers and/or pathways that could be used in human studies to determine agents that would mimic calorie restriction.”

Elevating Estrogen

Traditional breast cancer treatment involves lowering estrogen, but a new study finds that the opposite may be beneficial when anti-estrogen treatments don’t work.

When the accepted wisdom for cancer treatment no longer works, sometimes the best idea is to try the reverse.

A team led by Dr. Matthew J. Ellis, an oncologist at Washington University in St. Louis’ Stieman Cancer Center and Barnes-Jewish Hospital, found that for metastatic breast cancer patients who no longer respond to traditional anti-estrogen treatments, a daily dose of estrogen may aid recovery. Doctors gave 66 postmenopausal women with metastatic breast cancer caused by excess estrogen, which accounts for 75 percent of all breast cancer tumors, and who had previously received the anti-estrogen treatment called aromatase inhibitor treatment either six or thirty grams of estrogen a day to see what would happen. Thirty percent of the tumors, which had reappeared or resumed growth under the anti-estrogen treatment, shrank or stopped growing.

“We found that estrogen treatment stopped disease progression in many patients,” Dr. Ellis says, “and was much better tolerated than chemotherapy would have been."

Dr. Ellis’s team was able to predict which women would respond the best by examining PET scans of the patients’ tumors. When tumors treated with estrogen flared or glowed on the scan, 80 percent of them experienced clinical benefits from the treatment. The lower dose of estrogen was just as effective as the higher dose, good news since the higher dose tended to cause more severe side effects such as breast tenderness, vomiting or headaches. The six-gram dose raises estrogen levels to that of an ovulating woman.

The thirty percent of women whose tumors benefited from the estrogen often saw a recurrence of cancer, but their tumors were often significantly more responsive to the aromatase inhibitor treatment that had previously failed.

About 40,000 women per year die from metastatic breast cancer, and this treatment, Dr. Ellis claims, could help thousands of them. The treatment costs less than a dollar a day to use.