Weight patterns affect kidney cancer risk, new research finds

Excess weight during mid-life is a known risk factor for kidney cancer. New research suggests that weight patterns throughout a person’s life are also important. This study was published in the journal CANCER, which is from the American Cancer Society. Researchers looked at data from 204,364 participants in the NIH-AARP Diet and Health Study. They collected information about their body mass index (BMI) at ages 18, 35, 50, and when they joined the study around age 61. Among these individuals, there were 1,425 cases of kidney cancer, specifically renal cell carcinoma (RCC). The results showed that a higher BMI at any age was linked to a greater risk of RCC and its different subtypes. For each 5-unit increase in BMI, there was a 10-40% higher risk. Participants who gained weight during adulthood, leading to overweight or obesity, had similar increased risks compared to those who maintained a normal BMI. Long-term excess weight was also tied to higher risks of aggressive and fatal RCC, along with clear cell RCC. However, the relationship was not significant for papillary and chromophobe RCC. Interestingly, losing weight, especially by 10% or more, reduced the risk of RCC. Notably, weight loss between the ages of 18-35 and after age 50 resulted in a significant decrease in RCC incidence. These findings highlight the importance of maintaining a healthy weight throughout life to lower the risk of kidney cancer. The study also suggests that losing weight later in life can be beneficial. It is advised to support programs that encourage healthy weight maintenance and weight loss. People are encouraged to consult their healthcare providers before starting any weight loss plan.