Is There A Connection Between Fat and Cancer?

Whenever anyone claims to be studying the _effects_ of having a fat body, they are also likely studying the effects of constant stigma, and the of a lifetime of weight cycling.More and more we are seeing the suggestion that being fat is connected to having cancer. Some sources lie and say that research shows that being fat causes cancer. Some are slightly less dishonest and claim that being fat is related to higher rates of some cancers. So what is true here? Let’s take a closer look.

What are they actually studying?

These studies look for correlations between larger bodies and types of cancer. Correlation means that the two things often (but not necessarily always) happen at the same time, not that one thing causes the other. In fact, the first thing you learn when you study research is that “correlation never ever, never ever, never ever, implies causation.” That’s because if A and B are correlated, it’s possible that A causes B, it’s possible that B causes A, it’s possible that they are both caused by a third factor, and it’s possible that they are actually unrelated. Implying causation when all you have is correlation is not only unprofessional and unethical, it can be harmful.

What variables aren’t they controlling for?

Studies attempt to control for confounding variables – these are extraneous variables that can ruin the experiment by affecting the variables being studied. In a society rife with weight stigma, where fat people are subject to a government-sponsored “war on obesity” that produces a tremendous amount of shame, stigma, bullying, and oppression, and where fat people are encouraged to diet early and often, there are some variables that can have a major effect on study outcomes that cannot be controlled for. Thus, whenever anyone is studying the “effects” of having a fat body, they are also studying the effects of constant stigma, and the effects of a lifetime of weight cycling (aka yo-yo dieting.)

That means that if something is actually causing a higher cancer risk, it’s just as likely that the culprit is stigma and/or weight cycling, and not body size. If that’s the case then a “public health” message that suggests that fat causes cancer, in a culture where people with health issues are stigmatized, will cause additional stigma and thus more cancer risk. And/or if weight cycling is actually the cause of cancer, recommending that fat people try to become thin(ner) as a way to reduce their cancer risk (when we know that the most likely outcome of dieting is weight-cycling) will actually increase cancer risk – that’s why we have to be extremely careful not to draw conclusions for correlation. The bottom line is that this so-called “public health” message is phenomenally irresponsible.

What Do They Want Us To Do? (Hint: follow the money.)

There isn’t a single study of any intentional weight loss method where more than a tiny fraction of people succeed at significant long-term weight loss. (For more in-depth information about the embarrassing state of weight loss research, check out this piece.) Stomach amputation surgery kills people, and often leaves the survivors with horrific lifelong side effects (you can’t find them in groups with names like “Weight Loss Surgery Ruined My Life.”) So the idea that we should risk our lives purposely create a disease state in our currently healthy digestive system to try to avoid a risk of cancer that may or may not have anything to do with our body size seems ill-advised at best.

If you’re anything like I was, you’ll also be surprised to learn that there is literally NO study that compares formerly fat people who have maintained weight loss to people who were always thin to see if they have similar health outcomes. The study has never been done – partly because there aren’t enough fat people who have maintained weight loss.

As usual, when it comes to the weight loss industry, we just have to follow the money. It turns out that a lot of this research about cancer was funded by weight loss companies, who are now using the research to try to sell their weight loss products. (With thanks to readers Kat and Maria for sending the info on this.)

So What Should We Do?

Just when you thought you were going to get through a post of mine withotut reading this: health is multi-faceted, not an obligation, a barometer of worthiness, not entirely within our control, and not guaranteed under any circumstances. The decision of how highly we prioritize our health and the path we take to get there is intensely personal – and it’s nobody’s business unless we ask them to make it their business. The problem (and the issue that public health needs to focus on) is that currently not everyone has access to the same choices and options because of issues like poverty, oppression, and for-profit healthcare and insurance.

So when it comes to the idea that fatness increases cancer risk, we each have to make our own decisions about what we believe, and how we react.  As for me, I think that bodies come in lots of different sizes for lots of different reasons, and I have not seen any evidence that attempts to manipulate our body size are likely to be effective, and I’ve seen tons of evidence (and my own experience corroborates) that attempts to manipulate body size lead to nothing but yo-yo dieting, and a life that was nothing like any life I would want to live.

Maybe I’m at greater risk for some health issues because I’m fat, but I’m also at greater risk for some health issues because I’m a cis-woman, and because of my genetics, and because of the places that I’ve chosen to live (and the places that I didn’t choose to live as a kid, ) and plenty of other reasons. That’s the way health goes, it’s a moving target and, as much as we’d like to think it was, a lot of it isn’t within our control.

So I’ll put my time and energy into ending medical fatphobia so that doctors will actually give me proper examinations to detect health issues and treat them properly, rather than just diagnosing me as fat and prescribing another diet with absolutely no reason to believe it will help. I’ll put my time and energy into trying to counteract the effects of a fatphobic society I’ll spend my time and energy giving my body my full-throated supported and being clear that, no matter my size, my health, what illnesses I may or may not have or be at risk of having, my level of ability or disability, my body is amazing and worthy of love and care.

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9 thoughts on “Is There A Connection Between Fat and Cancer?

  1. I’ve been watching these “studies” for a while. So now fat causes cancer, huh? A few weeks ago, it was drinking that was causing cancer (specifically breast cancer). & a while ago, it was birth control pills.

    You know what this is all about? Shaming women into cultural compliance. Thin & sober & pure.

    Love your blog.

  2. If fat causes cancer, why do fat people have a better survival rate than thin people? The cause actually helps to cure?

    Maybe it’s something else.

    I’m no scientist, and I’m no gambler, but if I were, I’d put my money on cortisol, the stress-hormone.

    1. I’m so stressed it isn’t even funny. I also have a familial history of cardiovascular problems, which, in my case, is compounded by having diabetes. Yet if I were to drop dead of a heart attack, the stresses from having to work a minimum wage job to never make ends meet and my familial history wouldn’t be cited. Nope, it would all be because I’m fatty fat fat.
      It makes me so angry that I could spit nails.

  3. Even if we assume that fat causes cancer (and I agree that the studies cited do not support that conclusion), what is the solution? Dieting? Well, for me that hasn’t worked out very well. I think I’ll just take the risk. Life is risk. If we avoided every risk out there, it would be quite boring! So, I’ll continue to drive cars and ride motorcycles, scuba dive, walk at night, and (horrors!) be fat.

  4. So two of my thin friends died of cancer, one just recently. Other friends who have had cancer survived, some average size, some a little larger. Looks to me like cancer attacks thin people as much as it attacks fat people.

    I’m much more interested in studies that try to find out what actually triggers cancers to start and what are the best medicines to fight them.

  5. My doctor cited the risks for endometrial cancer (which I may be in the early stages of, it hasn’t been confirmed yet) as being a woman (duh), between the ages of 50 and 60, being white, and obesity. I asked her not to use the “o” word, and she has been respectful regarding that request. She made the mistake of thinking it was a “better” way of saying “fat,” which I informed her it isn’t. I may cuss like the proverbial longshoreman, but I think “obese” is a much nastier word than any f bomb I may drop.
    Well, let’s look at this. I can’t much turn back the clock, so stopping myself from being between 50 and 60 is right out. I suppose I could get a really dark tan, but the likelihood is I’d end up looking burned rather than tan. Oh, and then there’s that nasty fat. I could just get rid of that.
    Not so much. Been there done that. Many, many, many times.
    I developed bulimia when I was 12 years old and also started yo-yo dieting.
    Funny enough, ,when I stopped dieting (at age 45), my weight finally stabilized.
    The last time I dieted was when I tried Atkins again after I was diagnosed with diabetes. I did lose weight, but I don’t think it had much to do with Atkins, which just ended up making me sick to my stomach from the Erythritol used to sweeten their shakes and bars. I think it had more to do with controlling my blood sugar in other ways. Because, shocker, insulin resistance can cause weight gain and make weight loss difficult.
    I really wasn’t looking to lose weight in any case, and I felt a lot better when I stopped doing Atkins.
    I’m a living, breathing example of how yo-yo dieting destroys a person’s metabolism.
    Wouldn’t it be nice if no-one felt compelled to fall into the yo-yo dieting cycle, which benefits no-one but the multi-billion dollar diet industry, ever again.

    1. Nobody would fall into it if they weren’t fed a pack of lies and hatred. Keep taking care of yourself in whatever way is best for you.

  6. Ain’t that the truth.
    It makes it even more difficult for me to deal with the damn probing of my privates (I have PTSD surrounding that due to sexual assault) knowing that my body is also being judged harshly for being fat. I’m probably going to opt for a hysterectomy anyway, but it kind of pisses me off that one of the reasons is because I never want to have to appear naked and have anyone poking at my business ever again.

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