Early Obesity Increases Risk of 8 Types of Cancer Later in Life

Being obese at a young age increases the risk of developing several different types of cancer later in life, according to a recent study published in Obesity Reviews.

Through a systematic review and meta-analysis of observational studies, the study authors aimed to determine the degree to which obesity increases the risk of 8 different types of cancers. Based on the evidence, they found that the risk of cancer later in life is higher for individuals aged 30 years or younger who are obese and the risk continues to climb as the person’s body mass index (BMI) increases.

For the review, the authors used 8 different cancer types: diffuse large B-cell lymphoma, esophageal adenocarcinoma, gastric cardia cancer, hepatocellular carcinoma, multiple myeloma, pancreatic cancer, renal cell cancer, and thyroid cancer. The authors analyzed 56 articles published between 1993 and 2018 representing 27,559 cancer cases.

In the final meta-analysis, the authors included both cohort and case-control studies, and all participants were aged 30 years or younger. Patient follow-ups ranged from 7.2 years to 40 years and cancer cases were identified via medical records and cancer registries.

With each 5 kg/m² increase in body weight at a young age, the risk of developing each type of cancer significantly increased. Overall, the obesity-related cancer risk varied from a 12% increase for thyroid cancer to 88% for esophageal adenocarcinoma, according to the authors.

Adults who were obese in their youth were more likely to remain obese, which could partially explain the association between early-life obesity and later-life obesity-related cancer risk. The authors also noted that obesity and cancer share several contributing factors, including poor diet and lack of physical activity. Obesity is also a risk factor for a variety of diseases that can contribute to cancer.

“Prevention of overweight and obesity and children, adolescents, and young adults should therefore be emphasized to reverse the obesity epidemic and thereby avoid further increases in the burden of cancer attributed to excess fatness,” the authors wrote in the study.

Overall, focusing on early interventions for individuals who are overweight or obese during childhood or young adulthood may help reduce the number of obesity-related cancers, they concluded.

References

Hidayat K, Du X, Shi B. Body fatness at a young age and risks of 8 types of cancer: systematic review and meta-analysis of observational studies. Obesity Reviews. 2018. https://doi.org/10.1111/obr.12705.

Study: Obesity at Young Age Increases Cancer Risk Later [news release]. AAFP’s website. https://www.aafp.org/news/health-of-the-public/20180831obesitycancer.html. Accessed September 6, 2018.