Recent findings presented by researchers at Genesis Prevention Center at University Hospital in South Manchester, England, at the 2011 CTRC-AACR San Antonio Breast Cancer Symposium, have demonstrated that an intermittent, low-carbohydrate diet is preferable to a standard and daily calorie-restricted diet to reduce weight and lower blood levels of insulin. High levels of insulin are linked to a greater risk of developing cancer.

The study, funded by the Genesis Breast Cancer Prevention Appeal, revealed that reducing carbohydrates for two days per week is superior for preventing breast cancer and other diseases compared with a standard, daily calorie-restricted diet, but researchers added that further study is required.

Michelle Harvie, Ph.D., SRD, a research dietician at the Genesis Prevention Center, who presented the study said:

“Weight loss and reduced insulin levels are required for breast cancer prevention, but [these levels] are difficult to achieve and maintain with conventional dietary approaches.”

Harvie and her team decided to compare three different diets over 4-months to assess the effects on weight loss and blood markers of breast cancer risk in 115 women who had a family history of breast cancer. The researchers randomly assigned patients with either a calorie-restricted, low-carbohydrate diet or an “ad lib” low-carbohydrate diet whereby patients were allowed to consume unlimited proteins and healthy fats, like lean meats, olives and nuts for 2 days per week, or a standard, calorie-restricted daily Mediterranean diet for seven days per week.

According to their findings, both intermittent low-carbohydrate diets were superior to the standard daily Mediterranean diet for weight loss, reduction of body fat and insulin resistance. The average loss in weight and body fat was about 4 kg (about 9 pounds) for the calorie-restricted, low-carb diet and the “ad lib” low-carb diet compared to 2.4 kilograms (about 5 pounds) with the standard dietary approach. The restricted low-carbohydrate diet reduced patients’ insulin resistance by 22%, with a reduction of 14% with the “ad lib” low-carbohydrate diet, compared with 4% for those who did the standard Mediterranean diet.

Harvie commented:

“It is interesting that the diet that only restricts carbohydrates but allows protein and fats is as effective as the calorie-restricted, low-carbohydrate diet.”

Harvie and her team are planning on studying carbohydrate intake and breast cancer.

Written by: Grace Rattue