The debate rages on about whether or not obesity is really harmful. There are those who believe it’s just a function of society. Others see signs of heart disease, cancer, diabetes, and of course joint damage due to the extra pressure placed on the joints. Unfortunately, while the link between obesity and type 2 diabetes or heart disease has been well established, it is now official that cancer is also walking hand in hand with it.
Researchers have been working on this for a while. They officially gathered thousands of samples in 2002 in 184 different countries. Then they looked at cancer rates in 2012. Those who has previously been measured with obesity had higher rates of colon, kidney, pancreatic, and postmenopausal cancers as it turned out.
But it’s worse than that. With something like colon or kidney cancer, most could easily see the connection. However, you might not see it initially. Researchers weren’t expecting to find 3.6% of new cases of cancer in 2012 (including skin cancer) being directly connected to cancer. According to researchers, it even explained why women had more cancer than men.
So how does all of this work? The exact connection varies between individuals according to researchers. Hormones seem to be a key part of obesity that can disrupt all of these different parts of your body into a state of cancer. George Wang, professor of human nutrition at Kansas State University and a researcher of obesity and cancer risk says,
Using animal models, we believe it’s mostly relate to hormone changes with obesity. For example, for breast cancer, one of the pathways is related to hormones that are produced by fat tissue and can lead to cancer development.
According to Wang, there is one hormone meant to stimulate healthy cell growth called IGF-1. He reports,
It’s what we call a survival hormone. In healthy people, it prevents apoptosis, or programmed cell death. The problem is, obese people’s level of IGF-1 may be twice that of a normal-weight person, allowing cells to proliferate too quickly. We believe that increases cancer risk.
So what about the growing obesity rates? If the average BMI had stayed the same as it was in 1982, experts estimated that we could have prevented 118,000 new cases of cancer in 2012 alone. There are of course other reasons why our cancer rates are as high as they are. Study co-author Nirmala Pandeya says,
Other important risk factors for cancer, such as smoking, are declining, but we see the proportion of overweight and obese men and women still rising in most countries. If this trend continues we are likely to see an increasing number of people diagnosed with cancers that could have been avoided by maintaining a healthy weight.
It is critical to stop obesity now, not just because of the cancer risk of course, but because of all of the factors. However, this is just one more piece of evidence that has been added to the pot