People and health specialists generally discuss the numerous health benefits of regular exercise- from managing one's weight and improving one's mood, to improving one's overall health. But does regular exercise reduce one's chances of getting cancer, as some on social media claim?

 Well, turns out that most of these claims are true- including the one about reducing the risk of cancer.

Cancer is a disease caused when cells divide uncontrollably and spread into surrounding tissues. In a normal, healthy body, cells multiply by a process called cell division. When cells grow old or are damaged, they die, and new cells replace them. However, there are instances when this orderly process of cell division and replacement breaks down, and abnormal or damaged cells proliferate and clump together as tumours. These tumours can be cancerous or non-cancerous.

Around 90% to 95% of cancer cases are attributed to environmental factors and the lifestyle of individuals, highlighting the potential role of diet and exercise in carcinogenesis, the process by which healthy cells transform into cancerous ones.

Exercise is consistently recognized as one of the key lifestyle changes that helps prevent cancer. It is a part of ten commandments suggested by Harvard Health Review (HHR) for cancer prevention.

“Physical activity has been linked to a reduced risk of colon cancer. Exercise also appears to reduce a woman's risk of breast and possibly reproductive cancers. Exercise will help protect you even if you don't lose weight,” reads the HHR’s third commandment.

Similarly, the evidence linking higher physical activity to lower cancer risk has come mainly from observational studies, in which individuals report on their physical activity and are followed for years for diagnoses of cancer.

Analyses of various studies has found that regular exercise reduces the risk for various types of malignancies - bladder cancer, breast cancer, colon cancer, endometrial cancer, esophageal cancer, kidney cancer, and stomach cancer -  by up to 10 to 25 percent.

There is also some evidence that physical activity is associated with a reduced risk of lung cancer.

“In a 2016 meta-analysis of 25 observational studies, physical activity was associated with reduced risk of lung cancer among former and current smokers but was not associated with risk of lung cancer among never smokers,” says a report published by the US-based National Cancer Institute.

Cancer Research UK (CRU) recommends incorporating small amounts of activity and exercise into one's daily routine to lose weight or keep a healthy weight, which, in turn, reduces cancer risk

“Keeping a healthy weight lowers your risk of 13 different cancer types. This includes two of the most common types of cancer (breast and bowel) and three of the hardest to treat cancers (pancreatic, oesophageal and gallbladder),” the CRU states on its website.

Indians need to engage in more physical exercise as the country holds the second largest population affected by cancer in Asia, following China.