Weight gain before age 40 linked to multiple cancers: Study

Individuals who are either overweight or obese before the age of 40 have an increased risk of developing different types of cancer, according to a study.

The results of the research, published in the International Journal of Epidemiology, revealed that people who are overweight before the age of 40 had 70 per cent increased risk of developing endometrial cancer, 58 per cent greater risk for renal-cell cancer, and 29 per cent more risk for colon cancer.

The study also added that the risk increased by 15 per cent for all obesity-related cancers in both sexes.

The researchers, including those from The University of Bergen in Norway, took two or more weight measurements of adults, obtained at least three years apart, and before a possible cancer diagnosis.

They used data from the 220,000 individuals part of the Me-Can study -- initiated in 2006 to investigate metabolic factors related to cancer risk.

The study noted that the pooled data from the Me-Can study included around 580,000 participants from Norway, Sweden, and Austria.

Of the 27,881 individuals who were diagnosed with cancer during follow-up health checks, 9761 (35 per cent) were obesity-related, the study noted.

According to the researchers, the obese participants -- with a Body Mass Index (BMI) over 30 -- at the first and second health examination had the highest risk of developing obesity-related cancer, compared to participants with a normal BMI.

"The risk increased by 64 percent for male participants, and 48 percent for females," said Tone Bjorge, co-author of the study from The University of Bergen.

While obesity is a known risk factor for several cancers, Bjorge said that the new study looked at the degree, timing, and duration of being overweight in relation to cancer risk.

The researchers added that overweight and obese adults had an increased risk of postmenopausal breast, endometrial, renal-cell, and colon cancer.

"Our key message is that preventing weight gain may be an important public health strategy to reduce the cancer risk," Bjorge said.