A research group led by Takaaki Konishi (Doctor of Medicine) of the University of Tokyo analyzed the data of about 45 women under the age of 80 in Japan, and found that if the BMI is 22 kg / m2 or more, there is a risk of developing breast cancer. It was shown to be low for the first time.
Breast cancer is the most common malignant tumor in women, and in Japan, it affects 9 in 1 women and is on the rise.Although multiple risks such as exposure to female hormones are known, obesity is the main risk factor regardless of race or region because fat cells are the main source of female hormone production after menopause.However, the peak age of breast cancer differs between East Asia (40s-50s) and Europe and the United States (70s), and before menopause, obese women have a lower risk of breast cancer in Europe and the United States and may be at higher risk in East Asia. The sex was pointed out, but the cause was unknown.
The research group analyzed 2005 women under the age of 1 who had a BMI measured during a medical examination from January 2020 to April 4.As a result, it was clarified that the risk of developing breast cancer is significantly lower when the BMI is 45 kg / m785,703 or more (BMI and the onset of breast cancer are inversely correlated under the age of 22). More than 2% of Japanese women are said to reach menopause after age 45, and this result is the first to show that BMI has the same risk of premenopausal breast cancer in East Asia as in the West.
From the results of this study, it is estimated that in East Asia, including Japan, where there are few obese people, breast cancer is likely to occur from the premenopausal 40s, but postmenopausal breast cancer at which obesity is a risk is relatively few.Therefore, considering the BMI distribution, it is possible that breast cancer screening from a young age may be more significant in Japan, especially in the 40s.In addition, the relationship between BMI and breast cancer risk may be regardless of race, and it is expected to contribute to the elucidation of the mechanism of breast cancer development.
