Last week, the charity Cancer UK started a campaign to tell people that obesity causes cancer – more on their website – https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/obesity-weight-and-cancer There’s a very good piece here pointing out that ‘cause’ and ‘correlation are not the same thing. https://medium.com/@laura_86024/an-open-letter-to-cancer-research-uk-19ecaa71b263
Humans are easily persuaded to see correlation as cause and effect – this is the basis of all superstitious thinking. We’re prone to seeing patterns even when no patterns exist. That there is a correlation between obesity and cancer is really important and needs investigating. Correlation means there is a good chance of underlying issues causing both. Unless you can identify a mechanism that means one thing results in another, it is not helpful to suggest there’s a causal link. So, what other options are there?
Stress. Some of us may store fat as a stress response – good article here https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3428710/ So adding to the stress of larger people by telling them their size is going to cause cancer may… wait for it… increase stress levels.
Alcohol has a lot of calories in it and is strongly linked to cancer risk in a mechanical way. Alcohol consumption could easily, for some people, be an underlying cause of both obesity and cancer risk.
Every article I’ve read about cancer avoidance has advocated having a good diet high in fruit and veg, and getting plenty of exercise. Poverty diets don’t deliver this, and a poor diet leaving you with low energy is not conducive to staying active. What if poverty causes cancer?
If you show up to the doctor with a health problem, and you are also a larger person, the odds are you will be diagnosed with fat. If you lose weight and don’t get better – as has happened to a number of people I know – you may then get your symptoms taken seriously. Being diagnosed as fat increases your risk of having the early signs of other conditions ignored. It’s not going to cause cancer, but it does mean you are at higher risk from any illness if you don’t get your symptoms properly investigated.
We’ve recently discovered, after years of being told that weight is the cause of diabetes, that there’s an impact from air pollution, too. Pollution is recognised as causing lung cancer, but according to the World Health Organisation website, there are questions to ask about the impact on other cancer risks. If you breathe it in, some of it is probably getting into the rest of your body. If pollutants can give you lung cancer it seems fair to ask what risk they pose for other cancers. Here’s a piece exploring whether air pollution might contribute to obesity – http://thescienceexplorer.com/brain-and-body/pollution-making-us-fat and another study about what happens when pollutants accumulate in your body fat – https://www.sciencedaily.com/releases/2015/02/150227084315.htm – studies are ongoing as to the health implications.
If you make obesity and cancer the responsibility of the individual, you don’t look at collective responsibility for pollution and poverty. It is easier to blame and shame an individual who is at risk, than it is to invest time and money helping them. It is painfully easy to persuade people that being fat is a personal failing and that shaming fat people is the best way to help them. There’s plenty of research out there that demonstrates blaming people for their body shape does not lead to productive, health-improving changes in behaviour.
It’s shit science. Correlation is not causality. There may well be a great many people for whom conventional weight loss tactics don’t work, and many underlying causes that link obesity and cancer that will be ignored if we insist on simply focusing on weight.