Obesity which makes people prone to many diseases may cause cancers too. It has been revealed that obesity increases risk of 13 different cancers in adolescents.
In a meta-analysis, researchers at Case Western Reserve University in the US found how obesity shifted certain cancers to younger age groups.
In 2016, nearly one in 10 new breast cancer cases, and one in four new thyroid cancer cases were in young people aged 20-44, according to the study published in the journal Obesity.
Scientists believe young people with body mass indexes (BMIs) over 30 are more likely to experience aggressive malignancies. The new research integrates animal studies, clinical trials, and public health data to help explain rising cancer rates among young adults.
Nathan A Berger from Case Western Reserve University said that even if young adults control obesity after a while, risk of cancer still remains. “If you are obese, you are at a higher risk of cancer. If you lose weight, it improves the prognosis and may lower your risk, but it never goes away completely,” Berger said.
“Even if one pathway is successfully blocked, obesity-induced cancer takes another path,” he further said.
How obesity causes cancer?
Obesity accelerates cancer progression in several ways including over-activating the immune system to produce harmful byproducts like peroxide and oxygen radicals that mutate DNA, the study said.
It also alters a person’s metabolism, causing growth factor and hormone imbalances that help cancer cells thrive.
In the gut, obesity changes intestine microbiota such that tumour – promoting species dominate, scientists revealed.