It is well-documented that taller people get significantly more cancers than shorter people. (Google, e.g., “Height and cancer incidence in the Million Women Study: prospective cohort, and meta-analysis of prospective studies of height and total cancer risk,” Lancet Oncol. 2011 Aug;12(8):785-94, or PMID 21782509.)
Why is this?
It isn’t complicated. Tall people (or obese people) are larger and, so, quantitatively they have more cells. A 200-lb person has upwards of 100% more cells than a 100-lb person. (Not quite 100%, because some cells are simply larger, but you get the idea…) That means 100% more cells that need replacing every so often and 100% more cell replications per year.
And guess what: most cancers are caused by random DNA errors during a stem cell replication.
(See, importantly,: “Variation in cancer risk among tissues can be explained by the number of stem cell divisions.” Tomasetti & Vogelstein, Science, 2015 Jan 2; 347(6217): 78–81, or PMID 25554788, and
“Stem cell divisions, somatic mutations, cancer etiology, and cancer prevention,” Science, 2017 Mar 24;355(6331):1330-1334, or PMID 28336671.)
So, twice the cells, twice the replications, twice the critical DNA errors, twice the resulting cancers.
Losing weight, unfortunately, doesn’t decrease cell count much. Temporarily lose water, yes. Decrease cell size, a little. But NOT lose actual cell count or absolute cell replication rate. That takes decades.
7
I think the research needs to examine the gut health and fiber intake of those who received a diagnosis before 45 vs. those that did not.
My guess would be that weight alone is not to be blamed
11
Will doctors share this with their overweight younger patients? Also, there should be some screening short of a colonoscopy which many avoid.
3
I know obesity in itself is linked to many things, but is this a different consequence of diet: perhaps the foods chosen not only cause weight gain but directly cause or stimulate colon cancer?
6
According to this reporting, the incidence of colon cancer was about 1.3 per 1,000 women under 45. A 93% increase in risk, although it sounds large, is an incidence of 2.5 cases per 1,000 women. This difference of 1.2 cases per one thousand can also be expressed as a difference in relative risk of .012%. This illustrates how absolute risk (93% increase) often sounds far worse than relative risk (0.12% increase).
13
Is it possible that these young women were underdiagnosed because they did not want to go to the doctor because they were dismissed with their complaints and told everything would be better if they just lost weight? Is it because of an active issue of bias against both women and the obese in medicine - so much of what women deal with is dealt with by telling them - oh, honey -- it's all in your head. I know, I've been there. I've lost more than 150 pounds and physicians treat me very differently now. (BTW - not one of them ever recommended a resting metabolic assessment to determine how many calories I really should be eating to lose weight rather than throwing generalities at me based upon tables.) We need to teach our doctors to listen to women when we complain.
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@Knitter215
"Is it possible that these young women were underdiagnosed because they did not want to go to the doctor because they were dismissed with their complaints and told everything would be better if they just lost weight? "
NO, it's not being 'under diagnosed' because of fat shaming. Obesity has a very strong and well identified relationship to many diseases (diabetes, vascular disease, cancers). At some point this idea of being tolerant of people's self induced obesity needs a reality check.
10
@RIO As someone who has lost 150 pounds and was told many erroneous things and had many problems overlooked by medical professionals because I was fat and they didn't think it mattered, or were told that if they just tried harder, or used a different diet, or , or, or - rather than testing their thyroid, asking why they were depressed or had anxiety and potentially medicated it, checked for insulin dependency - rather than just saying lose weight and you'll feel better.
After 2 or 3 of those visits, you stop going to the doctor - even when you are sick. Because their answer isn't going to be about your problem - which may or may not have to do with obesity.
11
The link between obesity and many diseases (heart, diabetes, cancer,etc) is well-known. That is why so many people find the the "body positive image" phenomenon so infuriating. It is never OK to bully someone about their weight, but it is wrong to embrace obesity.
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@BMD
I don't think so. People are too judgmental, especially insecure young women and cruel young men. There's a lot of bullying of women about their weight. A lot of the body positive movement also supports people looking simply different rather than conforming to a model ideal, or supports women being strong through exercise. It supports reality based weight and looks rather than airbrushed, such as the changes women go through with pregnancy. I really feel it's up to both individuals and physicians to help individuals, children, and families begin to address their weight through a health frame, not a blame frame, or I eat this diet, you should too. The aim for weight should be healthy, not sexy.
9