A Spanish study in Almost a thousand women with breast cancer have determined that those who consume more calories than they need are more prone to getting tumors of this type. Similarly, a calorie restriction seems to prevent the risk of developing the disease.
The work is done by researchers from Carlos III Health Institute, which belongs to the biomedical research consortium of the Epidemiology and Public Health Network (CIBERESP) and the GEICAM Breast Cancer Research Group. It has been funded by the Spanish Association for Cancer (AECC) and has been published in the journal & # 39; Scientific Reports & # 39; by the Nature Group.
The study was conducted at 23 hospitals in nine autonomous communities
breast cancer, with 32,825 new cases in 2018, It is the most common tumor in Spanish women. It accounts for 29% of the cancer cases in women, making it a serious public health problem. There are clear signs of obesity and weight gain are key factors for breast cancer in postmenopausal women.
However, the evidence of limiting the number of calories is less essential. Experimental studies has shown that the limitation of weight gain due to calorie restriction exerts a preventive effect on breast cancer.
The doctor Marina Pollán, Scientific Director of CIBERESP, has led the work, which originated in the studies of American researcher Eugenia Calle, who found in a group of one and a half million people that obesity was related to a higher mortality from cancer. The speakers of Alimente recognize Dr. Pollán, that "in Calle's opinion, Eating too much is the leading cause of cancer in non-smokers. And since we are in the midst of the obesity epidemic, I came up with the idea of trying to eat more if it means an increase in risk, "he recalls.
The research has counted on the participation of researchers 23 hospitals in nine autonomous communities: has assessed the relationship between the risk of breast cancer and deficient or excessive calorie consumption based on the body's mass index, physical activity and basal metabolic rate for each participating woman.
For this 973 newly diagnosed women with breast cancer were recruited and another 973 healthy women. In both groups, women between the ages of 18 and 70 were old. Each patient was mated with a healthy woman of the same age, from the same city and without family ties. Participants responded to the food frequency questionnaire from which the average daily energy intake (kilocalories / day) was estimated during the five years prior to the interview and an epidemiological questionnaire with lifestyle information and other relevant information. the investigation
The results they showed it women with lower calorie intake than expected, according to their individual energy needs, produced a lower risk of developing breast cancer. This effect was greater in pre-menopausal women.
On the contrary, women whose calorie consumption exceeded 40% of the expected values, produced almost double the risk of suffering from breast cancer of any subtype, that the participants have an energy intake within the appropriate levels. This last effect was particularly pronounced in postmenopausal women and in women with low adherence to the Mediterranean diet pattern.
"Even the risk is higher in pre-menopausal women, where the body mass index is not associated with breast cancer. To prevent breast cancer, it is a good recommendation to try that the calorie intake is not excessive. And this must happen before menopause begins, "recommends the expert, who also heads the area of environmental epidemiology and cancer at the Carlos III Health Institute.
"The highest calorie intake with mammographic density, another cancer marker"
In addition, the study offers data on breast cancer risk associated with diet in each tumor type. "The results reveal it to each 20% increase in relative caloric intake – What is the observed intake relative to the expected intake, increases the risk of developing a breast tumor with positive hormone receptors or a HER2 + tumor by 13%, which is 7% in triple negative tumors, the doctor says. Miguel Martín, Chairman of the GEICAM Group.
"This is the first study of its kind and we want to do more work in this regard. And with the same method, we also published a few months ago another work that prohibited excessive calorie intake with mammographic densitywhich is another risk marker for breast cancer. We find the same relationship that makes us believe that these results should be passed on to the population: eating more is an important risk factor for breast cancer, "Dr. Pollán concludes.