Obesity and cancer third most important risk factor for cancer in the United States, just behind tobacco and diet (see Figure). Obesity is the source of about 15% of all preventable cancers. In 2018, Chinese researchers performed a systematic review and comprehensive quantitative meta‐analysis of cohort studies reporting body mass index (BMI) and the risk of 23 cancer types, providing epidemiological evidence supporting the association between BMI and cancer risk. The strongest positive association between BMI and cancer risk was found among patients in North America. The mechanisms by which obesity may increase the risk of cancer are not well understood, but it
Thermal equator both "summer" and "winter." Chennai, India, at 13 degrees north is considered to lie on the thermal equator at its longitude (80 degrees east). Thermal equator The thermal equator (also known as "the heat equator") is a belt encircling the Earth, defined by the set of locations having the highest mean annual temperature at each longitude around the globe. Because local temperatures are sensitive to the geography of a region, mountain ranges and ocean currents ensure that smooth temperature gradients (such as might be found if the Earth were uniform in composition and devoid of surface irregularities) are impossible, the