A new study in the United States has highlighted the role that calorie intake may play in the development of breast cancer.
Researchers discovered that when radiotherapy was being used to treat breast cancer in women with a specific form of the disease, the treatment was more effective if their calorie intake was lower.
The “triple negative” form of breast cancer is a particularly aggressive form of breast cancer and affects about 20% of all women with breast cancer. This form of cancer also tends to be found more often in young women, below 40 years of age.
Women with this form of breast cancer often see it spread very quickly with stubborn tumors returning after treatment.
Researchers aren’t sure why a reduced calorie intake helps prevent the tumors return, but it may be to do with reduced calorie intake changing the tissue surrounding the tumor.
The problem is that many of the treatments which women are given to help them fight cancer promote weight gain. Treatments like hormonal therapy and steroids which are used to slow the growth of tumors can increase weight gain by slowing metabolism, making the tumors more resilient!
We know from other studies that being overweight is actually linked to breast cancer if you have a particular genetic marker. Many other forms of cancer are also linked to being over weight, so there are plenty of reasons to maintain your fitness and weight.
Studies also show that breast cancer treatment is less effective if you are overweight and people who gain a lot of weight during their breast cancer treatment are likely to have worse outcomes.
These studies have made researchers more interested in the role of metabolism in the treatment of cancer. If they can make sure the treatments don’t adversely affect metabolism and induce weight gain in patients, then better outcomes for patients are more likely.
Dr Nicole Simone, the study leader of the most recent research says that from the findings: ‘We found that the diet turned on a programme that protected mice from metastatic disease,’. The study was published in the journal Breast Cancer Research and Treatment, and found that in the dieting mice, cancer cells decreased their production of microRNAs 17 and 20 (miR 17/20).
Those two molecules play an important role in influencing disease pathways. In the triple negative breast cancer patients, this group of MicroRNAs is usually larger.
Researchers used mice in the study and found that the mice who undertook radiation and calorie restriction had the best outcomes.
This latest research is only one of many studies that backup the role of a healthy diet, exercise and maintaining a healthy weight. In 2009 a study at the University of Alabama at Birmingham (UAB) found that:
restricting consumption of glucose, the most common dietary sugar, can extend the life of healthy human-lung cells and speed the death of precancerous human-lung cells, reducing cancer’s spread and growth rate.
Which researchers saw as another indicator that moderating calorie intake helps prevent cancer.
However this is not an argument for unhealthy dieting, but rather an argument for maintaining a healthy and balanced diet, exercising and avoiding processed foods.
The excess weight and cancer link is not a new one either. In 1987 studies were suggesting that people watch their weight: “a complete review of the data suggests that reducing caloric intake and relative body weight may lead to a considerable decrease in cancer risk in humans.”