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Overweight and obesity are linked to cancer (cdc.gov)
175 points by chiefalchemist 9 months ago | hide | past | web | favorite | 129 comments

From the sidebar:

> good health is the best prescription for preventing chronic diseases

That's bad enough to approach self-parody, but in a way it's very illustrative of the fact that apart from smoking cessation and arguably some other forms of drug addiction treatment, we have very little in the way of demonstrably effective lifestyle interventions to prevent chronic illness. There are mountains of epidemiological associations and sometimes even plausible physiological mechanisms for many of these things, but it often turns out that the obvious intervention just defies the correlation instead of changing the outcome (cf. Goodhart's law), or changes things in a statistically significant but practically underwhelming way.

As far as I know, obesity is mostly significant as a public health issue because it makes many conditions modestly worse, not because it's the primary cause of any given problem. Losing weight might mitigate an illness such that you cross some diagnostic threshold and are thus "cured", but you're still in a much different state than someone who wasn't at risk of that illness at any weight. That doesn't mean you shouldn't try to maintain a healthy weight, just that it's wishful thinking to expect that doing so is going to solve all or even most of your problems. In general, it's important to recognize that health is a complex topic and not fool ourselves into thinking we've found the key to good health.

Put another way...if you have a serious medial issue being overweight can be the difference between life and death.

Instead, we have Oprah selling "love your body" as if that love will save you went a health crisis comes knocking.

Loving your body while you're overweight and getting to a healthier weight are not at cross purposes. Shame causes people to dissociate with their bodies which makes exercise and healthy eating harder.

The fact that we are encouraged to think of being overweight as a personality flaw makes it much harder for people to lose weight. They take their weight as evidence of their weakness which causes a detrimental cycle.

It's also true that popular notions of "healthy weight" are medically inaccurate. Many people who are a normal healthy weight and have no medical reason to lose weight still think they are overweight.

There are lots of good reasons to encourage people to think of themselves as healthy at non-skinny sizes.

There's also a huge amount of distorted thinking about the relationship between body shape and weight or body fatness. For example, it's extremely common for people to believe (and dishonest elements of the "fitness industry" to promote) that there's some diet or exercise to change a feature that's primarily determined by skeletal structure or muscle insertions (peaked biceps, thigh gap, etc.).

> Many people who are a normal healthy weight and have no medical reason to lose weight still think they are overweight.

Many of those people probably _are_ overweight. If your bmi is greater than 25 and you’re not weightlifting (and eating to support that), you’re almost certainly overweight.

Many people who are overweight are using the love your body campaigns for justification of their weight, when they are actually overweight.

How can someone with no medical reason to lose weight be overweight? That's a contradiction. Think about what "over weight" means.

Many people who _think_ they're not overweight are in fact overweight. Just because you believe you're a healthy weight doesn't mean you are, and just because you are the same weight as everyone else doesn't mean you are a healthy weight.

There is nothing humanity does that isn’t used at cross purposes by people who are missing or subverting the original point.

The fact is that shame keeps people from being able to engage with their body and maintain the work needed to lose weight.



Your paraphrasing of the parent post is incorrect and misleading.

I'm open to learning why you think this. I was trying to accurately reflect the message I believe underlies the sentence that I quoted. If you think the statement "people believe they're going to be fine with diabetes, as long as they love their bodies" implies something different, please be specific. It still appears to me that the message is "people who watch Oprah or otherwise develop a positive body image, even if they are overweight, believe this positivity protects them from harmful medical conditions like diabetes that might be related to their body's general condition."

Why I think what? Glad to clarify. What part of the Oprah propaganda machine isn't clear?

I'd be more worried about Oprah being an eager springboard for the next Dr. Oz or Rhonda Byrne, who encourage people to embrace utter nonsense and snake oil. At least "love your body" in a broad sense is compatible with the concept of optimizing it.

> Instead, we have Oprah selling "love your body" as if that love will save you went a health crisis comes knocking.

Pretty sure you only brought that up because you perceive Oprah as being overweight. "Love your body" is one of NOW Foundation's programs. The program description is:

> Every day, in so many ways, the beauty industry (and the media in general) tell women and girls that being admired, envied and desired based on their looks is a primary function of true womanhood. The beauty template women are expected to follow is extremely narrow, unrealistic and frequently hazardous to their health. The Love Your Body campaign challenges the message that a woman’s value is best measured through her willingness and ability to embody current beauty standards.

Oprah helped advertise and promote that program.

Being obese makes diabetes pretty substantially more likely.

Being overweight or the diet associated with being overweight? Particularly with recent research showing that the gap between periods of consumption can help the pancreas regenerate[0].

[0] https://www.ncbi.nlm.nih.gov/pubmedhealth/behindtheheadlines...

That's an interesting question, but I guess I don't understand the point of the distinction? If you're just pointing it out, ya, I think that's an interesting question to consider. But for practical purposes i'm not sure there's a difference.

A diet full of starches and sugar, a diet of almost only fat and meat, and a diet of mostly the two combined could all lead to obesity. Are they equally likely to lead to diabetes? Is it obesity, or a correlation between obesity and drinking your own weight in Coke every week that is the highest risk factor?

With a sample of n=1 I have close family member who developed diabetes with a perfectly “healthy” diet, just out of control portion sizes. Since losing weight, they’re “cured”.

I would guess overweight in and of itself. Being overweight puts your body in a pro-inflammatory state; a pro-inflammatory state makes auto-immune (etc.) disease more likely. So would be surprised if they were not linked. One way to guage might be to take people are are overweight _but are not gaining weight_ -- and compare them to people who are gaining weight (regardless of current weight). Probably a hard study to do.

So is it that the high refined carb diet causes overweight which causes diabetes, or is it that the diet directly causes diabetes, and also directly causes overweight?

In either case, the smart thing would be to avoid the high refined carb diet.

It's not "bad," it's the paradoxical truth. Sort of how people say, limit sodium intake to prevent high blood pressure. When all the studies say it's ok to eat as much sodium as you want, as long as you're healthy. But if you have high blood pressure or compromised kidneys, you should limit it.

There is some good quality evidence for dietary interventions snd cardio/cerebrovascular disease/cancer, although it is difficult to interpret and nutritional science in general is a disaster.

Without too much exaggeration, exercise also improves every surrogate and hard end point ever tested.

Eg http://www.nejm.org/doi/full/10.1056/NEJMoa1200303 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4415727/

I'm in the opposite group. I really think it is that obvious that good health and exercise is the key to a long life.

I think all you really have to do is take a look at nearly anyone over 80+ .. the vast majority of the people who make it to these ages or older have a few things in common, and we can call it coincidence, but it's probably not.

If you don't want to be sick then don't be!

Eating kills you. Heart disease kills 614,348 people per year & cancer kills 591,699 per year [i]. Heart disease has been linked to saturated fat for years. Cancer is your own cells that have mutated. Each new cell is just ticket to the cancer lotto. Obesity = more cells. Cancer & Heart disease kill over a million per year. But we spend most of our media time on shootings and snake bites, in reality it's that bag of Cool Ranch Doritos (which are a curse on humanity).

[i] https://www.medicalnewstoday.com/articles/282929.php

> Obesity = more cells

That's not true. Not only do fat cells just grow bigger (a skinny person has just as many as a fat person), you'd expect the increase in cancers to be mostly liposarcomas ("fat cell cancer"), which stay very rare.

Other organs might be distended or enlarged, but they don't contain more cells.

The reason obesity leads to cancer is not very well understood, but it's probably a complicated process involving abnormal hormone levels usual in obese people, and the constant low-grade inflammation their body is usually suffering from

I don't believe this is how it works.


I'm no longer deeply involved in this area so my information might be dated, though years ago it was pretty well understood based on the evidence that fat cells were created _and_ grew bigger as person got heavier, however, fat cells (once created) were never eliminated from the body, meaning they would shrink though they would be around forever once created.

It was also understood (if I recall correctly) that the faster someone gained fat, the easier it was for fat cells to be created. Meaning rapid weight gain was more likely to create new fat cells. (not sure if I'm remembering that one right)

It was surmised from these that this is why rebound weight gain (aside from rebound lifestyle factors) was quite easy for many, particularly the incredibly obese. It was also why it was strongly recommended to take fat gain incredibly seriously as the creation of fat cells was deemed potentially lifelong damaging.

> That's not true

Do you have a source for that? I find that claim interesting because I'd be surprised if obesity != more cells.

Update: I found this link about a study that found as you gain weight, you grow new fat cells (2010). I can't find the paper though.


Update 2: I believe this is the paper: https://www.ncbi.nlm.nih.gov/pubmed/?term=20921416%5Buid%5D

Update 3: Another paper that found growth of new fat cells on weight gain (2015): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4380653/

From this article found in this thread: https://news.yale.edu/2015/03/02/new-fat-cells-created-quick...

How can that be true? Don't fat people at least have more skin cells than skinny people? Also, I can't imagine that enormously obese people just have larger fat cells than skinny people. I have read that it is harder to get rid of fat cells once they shrink, but not that we don't get more of them.

A common misunderstanding is that organs are made up entirely of "cells" but, they are not. There are other materials involved, such as collagen. We call these names like "connective tissues" and they take up a lot of the space.

That doesn't mean they aren't involved, proteins can go wrong, but, that is usually associated with other types of diseases besides cancer.

That still leaves me confused. A skinny adult who becomes obese has the same number of skin cells? That sounds hard to believe.

I would like to point out also, that many people who would be described as "skinny" would almost never become obese. Neither would they be able to put on much muscle mass. It is a huge misconception that our bodies are just blank templates that can become fatter or more muscular. Different bodies have affinities for different shapes.

Someone who is very ectomorphic and "scrawny", will often have severe difficulty gaining a substantial amount of weight.

I disagree, (would be open to sourcing from this) but there are photos of people I know from 15-20 years ago where you would look at them and think they’re scrawny, and now they are visibly obese.

Sorry, but this just sounds wrong. Even if the only evidence I can point to is life experience.

Stretch marks are the areas where fibroblasts just lay down a thin patch of fibers because there's insufficient ability to grow skin to keep up with the required surface area.

Oh sure they increase, but, not at a plainly obvious rate, it depends on the tissue and the like. But the majority of that mass is not cells.

Yes, the number of skin cells will increase. They will also need more blood vessel cells, immune cells, etc.

What about muscle? Does that follow the same thing as fat cells, they just stretch/grow, not increase in count? I always just assumed more cells were created as you got bigger.

Human muscle cells experience hypertrophy (growth) but not hyperplasia (increase in number). (Post-puberty, anyway)

The low grade inflam and hormones are definitely causal. Another that biologists don't really from is the simple increased temp these people live at due to fat being insulation: Simple thermodynamics starts to creep in over 50 years.

Speaking of hormones, being overweight or obese may also increase the risk of breast cancer. The development of breast cancer involves estrogen, and fat cells produce estrogen.

Excess fat tissue also isn't vascularized to the same degree normal quantities of tissue are, resulting in an inflammatory cascade via Hypoxia- Induced Factor.

I have a rather large amount of loose skin that begs to differ with your "Obesity != more cells" assertion.

The link between saturated fats and disease is dubious at best. Here’s[1] a meta-analysis with 350,000 subjects that failed to show a link between saturated fat, coronary heart disease, stroke and cardiovascular disease. Many meta-analyses[2] fail to show a correlation, and many remain unpublished.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2824152/

[2] http://www.bmj.com/content/351/bmj.h3978

I think the people who want the world to be vegetarian for non-health related reasons (e.g animal rights advocates, environmentalists) push the largely discredited "saturated fat is bad, carbs are good" dogma because saturated fat is mainly present in meats and not in vegetables with some rare exceptions such as avocados and tropical plant oils. Also, carbohydrates are not present in meats, but plentiful in vegetables.

and many remain unpublished.


The scientific consensus is that saturated fat is a risk factor for cardiovascular disease, having been endorsed by many medical, scientific, heart-health, governmental and intergovernmental, and professional authorities, such as the World Health Organization,[1] the Food and Nutrition Board of the National Academy of Medicine,[2] the American Dietetic Association,[3] the Dietitians of Canada,[3] the British Dietetic Association,[4] American Heart Association,[5] the British Heart Foundation,[6] the Heart and Stroke Foundation of Canada,[7] the World Heart Federation,[8] the British...


Actually a lot of these xx Is bad for you are dubious or just well marketed fads eg lo salt as my specialised NHS dietician (for chronic kidney failure) commented they don't tell you what C$%^ the put in to replace salt

a bag of cool ranch doritos has 1 gram of saturated fat. saturated fat is not linked with heart disease


Total fat and saturated and unsaturated fats were not significantly associated with risk of myocardial infarction or cardiovascular disease mortality.

Rather the opposite, in fact, which is kind of hilarious to me.

> Intake of total fat and each type of fat was associated with lower risk of total mortality...

It is hilarious, although I left it the lower risk of all type mortality since OP was specifically talking about saturated fat being linked to heart disease. But yes people should probably eat less pasta and more steak

Yeah. Lets all go on a Keto diet and sustain 400 million americans on steak. Do you people ever stop and think about the consequences of your diet?

Keto is a high fat diet not a high protien diet. Replace "keto" with "Atkin's" and I have no issue with your comment, in fact i would agree.

I think it’s the number of people which is the problem. Also, there are not 400m Americans. Yet.

Funny, if you flip to any recent thread about climate change, you're likely to come across someone advocating less steak and more pasta. Why? Producing meat is incredibly resource-intensive; cows are the biggest offenders. They literally shit greenhouse gas.

Which is not to say I don't enjoy a nice juicy cheezburger. Damned if you do, damned if you don't.

1 gram per serving.

Most of their packages contain multiple servings. Even the smaller packages that you usually see on the shelf are 3 servings, at least in the US.

A steak has roughly 21g of sat fat per serving, though. So you'd have to eat 7 bags of Doritos to eat the equivalent of a steak.

My point is not that Doritos aren't bad for you but that saturated fat isn't the reason they're bad

Yes. But they aren't good for you either. They're digestive spam. And as a result the body will continue to seek the nutrition it needs. Feed it more unnecessary calories and it will keep looking.

Eventually, "you are what you eat" catches up to you.

No disagreement here. As I said, it's not that they aren't bad, it's that saturated fat isn't the reason they're bad. I'm with you that doritos should be nixed from any person's regular diet

I'm more fearful of sugar and simple carbs than sat fats.

So.. how much is a serving? Wherever I eat steaks that seems to vary wildly. In any case the variation is too big to warrant giving such a precise number (21 grams) for the amount of fat.

The fun size bags have one serving, but even so I doubt that doritos, en masse, are to blame for obesity. It's the accompanying sedentary lifestyle that is the real culprit.

If we want a food source to blame, look at high sugar content foods like soda or the slew of 'Little Debbie' type snacks (I'm preferential to Nutter Butters) that can be consumed in one or two sittings if you aren't calorie conscious.

But, just to reiterate what's important, if we all just got a solid hour of exercise each day the rate of cancer and heart disease would drop appreciably.

> if we all just got a solid hour of exercise each day the rate of cancer and heart disease would drop appreciably.

But people really want a magic bullet, "X is bad, Y is good". People generally do not like to exercise so they'll keep looking for something else.

Conversely, junk food companies love to shift the blame to the consumers not getting enough exercise.

I don’t disagree that the sedantary lifestyle is the primary cause. However the processed food industry is a dangerous trap; Doritos and their ilk are almost as dangerous as those other sugary snacks, they are just a different kind of addictive, using fats, salt and MSG instead of sugar


Add to that #3 on the list, the 250,000 Americans that die each year from medical errors.

>But we spend most of our media time on shootings and snake bites, in reality it's that bag of Cool Ranch Doritos (which are a curse on humanity).

We really going to worry about a bag of chips when so many people still smoke?

Smoking has been falling constantly and it is now 1/3 the level it was 40 years ago. Not only is it falling, but the rate at which it is declining is increasing. OTOH Americans apparently cannot, under any circumstances, stop shoveling Oreos and Twinkies into their mouths. There are far more obese Americans than there are Americans who consume tobacco products and the obesity rate is going up. Any resources spent on reducing obesity will deliver greater returns than that spent on reducing smoking, even given the greater risk that smoking represents at the individual level.

More cells + a compromised system* = Problems.

The problem is people aren't interested in health. Oreos are a God given right, evidently. And it's easier to blame the healthcare system than to face the truth. That is, you are what you consume.

*The report is just cancer, but diabetes will be just as happy to kill too.

This might be completely inaccurate, but I've always thought of the body as a machine, and it has moving parts. And as with any machine, the more its parts move and get used over time, the sooner the machine will wear out. And if you eat more, regardless of whether it's healthy or not, just the quantity itself, you are going to make the parts inside you move more to process the digestion. Eating less puts less stress on your system over time, as long as you are of course not under p-eating by an alarming amount.

But that would mean a direct relationship between physical exercise and death, which I believe is not the case.

I don't follow. The body spends much more time digesting food than is normally spent exercising.

I've read that constant digesting gets in the way of the body doing nightly internal cleanup processes that detox your system, as energy is diverted to process food instead. That might be another source of problems.

The more exercise you do the more you have to eat to maintain your body. If you are following a healthy diet you will need to increase even more your total amount of food due the fact that generally healthy food has less calories. Also, there is nothing more stressful for the body than exercise.

> there is nothing more stressful for the body than exercise

I think you are postulating. There was an article here a week or two ago that showed how bodies frequently in motion tend to live longer and be healthiest. There are different types of effects on the body from activities, and I'd be willing to bet that a body that's constantly in a state of digestion is stressed more than one in natural motion. However, I say this with a disclaimer that I'm guessing based on recent articles posted here. But if you really think otherwise, you should just provide a source.

Also, unless you are training for the Olympics, you do not need to linearly scale your food intake in proportion to your exercise. The average diet for many people does not need to change much after introducing exercise because the average diet already is usually too many calories.

> Also, unless you are training for the Olympics, you do not need to linearly scale your food intake in proportion to your exercise.

Lets assume that you are. Would that mean you will die earlier? Does that mean that the more exercise you do the earlier you die?

If everything else is kept the same (never true), that would be correct. Like everything else in this area of research (which depends upon NHST), you will find conflicting studies if you search. Here are some layperson sources (I didn't bother looking deeper):



You mean you can have too much of a good thing. Say it ain't so nonbel.

"More than half of Americans that overweight and obesity can increase their risk for cancer."

Sorry to be 'that guy', but I'd expect official statements from the CDC to be better proof-read as this sort of thing really does impact the credibility of the message.

You might want to append a (sic.) to the quote. I assumed you made the typo until I read the follow-up.

Curious if it's cause, or shared effect. Like perhaps the diet of an obese person generally has a higher amount of carcinogens, or lacks in some key antioxidants...in addition to making you overweight.

Obese people probably produce elevated levels of insulin-like growth factors over time due to their dietary choices. IGF-1 is already understood to increase cancer rates.

Intermittent fasting studies tend to focus on IGF-1 levels in the interests of slowing aging, which is of course strongly related to cancer prevention.

it doesn't really matter if it is or not, some studies say yes others say no. Bottom line is it sucks to be fat and overweight, e.g. you have less energy and life is just less fun.

I used to weigh well over 300lbs, and I eventually took up a hobby that made me want to lose it badly enough to go through the trouble of making my body eat half of itself.

I don't get to order pizza. I don't get to pick up something from a fast food joint on the way home. I can't go to a restaurant with friends. I have to avoid gatherings where free food will be present. I dread the days a coworker brings in donuts. I've had to get used to going to bed hungry. I usually don't have much energy at all because my caloric intake has to be restricted so much to prevent me from gaining weight back, so I take stimulants to suppress appetite and make it possible to get through the day without falling asleep at my desk. I am a slave to the scale.

So I guess what I'm saying is that I disagree with your statement. Oh, it sucked to be fat alright, because people treated me like shit just for existing and because it was embarrassing every time I broke a chair, but I wouldn't say I had less energy and I definitely wouldn't say I had less fun either.

My personal experience is very similar and you described it in a way better than I could. And then add on to that the requirement to do that day in and day out for the rest of your life.

Thank you for sharing.

What about stuff like how after losing weight I notice myself running to catch a bus? I _never_ would have done that in the past.

Or even the other day I realized I was taking steps two at a time! Woah! That is Not the old me.

Slightly OT, but I was just reading some fascinating comments in [1]. The post was about cancer and mitochondria.

Particularly for me, the series of comments about how the nervous system can play a role in cancer development (via inflammation promoting activity) is fascinating.

There are even some comments from Carlos Monteiro, a controversial cardiologist. He postulates that cardiac glycosides (used to treat cardiac problems) are also a potent anti-cancer drug.

[1] https://joshmitteldorf.scienceblog.com/2017/10/01/is-cancer-...

[2] http://www.infarctcombat.org/cm/homepage.html

Not exactly news but worth being mentioned from time to time.

Obesity is due to the Metabolic Syndrome, i.e. it is strongly linked to diabetes. Watch the presentation below, which I recorded at our church, which is about the leading UCLA research on linking diabetes and cancer: https://www.youtube.com/watch?v=KSo-p7DafpA

Relevant (fascinating!) talk from another thread[1]: https://overcast.fm/+FaTQX2SRE

[1] https://news.ycombinator.com/item?id=15424339

Point taken, but who wrote that? It's hard to establish credibility when your authors write like a 3rd grader.

Public health officials do sometimes intentionally write at a 3rd grade level in order to reach the widest possible audience.

Are you suggesting that bad grammar and usage in a scientific article increase one's audience?

irrespective of cancer being linked with being Obese, it is always better to remain active. naturally our body is not designed to have a sedentary lifestyle. So study can be taken as a reminder to stay active and not being a couch potato. take frequent breaks and have some active lifestyle.

and mental health issues (ex: depression, anxiety, post-traumatic stress disorder (PTSD), binge eating disorder, and night eating syndrome.) are linked to obesity.

The more the cells the higher the chance for a mutation?

The older we get the more opportunity for cell mutation?

I don't understand why any comments in support of this article are being downvoted. Is it now politically incorrect to support agree with scientific studies?

Reminds me of climate change deniers.

Ha. I don't understand why people need a formal study to understand the human body system 101. That is, compromise that system - which is what excess weight does - and (bad) things are going to happen.

I mean if your infrastructure (e.g., bones, major organs, etc.) are designed to support a mass of X and you're more than 1.1 times that mass then there are going to be "side effects."

And people wonder why healthcare costs are so high? Maybe that's because excess weight also compromises brain function.

We've had all the science we need. What we lack is the ability to handle the truth.

Well, climate change science doesn't offend anyone. The science from the article does.

This (ignoring facts one finds offensive) is a very serious problem in our society, does anyone know of research into how to work around it?

Most of the research I’m familiar with is related to cognitive biases from areas related to political science or religious beliefs and it’s very obvious now that facts are not a way to get people to believe things that were initially spurred by emotional reasons. Most of the stuff I’ve seen basically says it’s impossible to get people to get past their cognitive dissonance problems without making something very personal that requires them to adapt or risk more or less a form of identity loss. In fact, facts may cause people to bank even more on their existing beliefs and seek out “alternative facts” that support their current beliefs. This is a similar mechanic to how some anti-LGBT politicians have relented on their publicly known positions when some of their immediate family members have come out as homosexual. This is not consistent either - many such persons are simply disowned by their families and in extreme cases of bigotry result in an honor killing.

My personal, not-very tested belief is that there is a strong biological component to political alignments and if you put that person in a different culture they’d gravitate toward similar values on a relative scale.


Discuss the arguments and the data not a consensus of opinions. Science isn't done that way. Not so long ago, margarine (industrially hydrogenated fat) was touted by a majority of recognized experts as a healthy option while butter and eggs were supposed to be the route to heart disease and stroke. Merely adopting a consensus view is a dice game.

But we've had the science. That is, we know that extra weight compromises the human system. For example, diabetes.

This report isn't new. It's not a surprise. We already knew that if you make the body do something outside the norm of natural (e.g., smoking) the odds of bad things happening is going to increase.

Sure it's nice to have micro proof of a cancer connextion. But at the macro level this is just new chapter in a pattern we've proven plenty of times before.

So is long distance running natural?

Periodic fasting?

Living on no meat?

Sitting on an elevated seat to defecate?

Eating bananas in the wintertime? Or in non-tropical regions?

Living surrounded by 1,000,000 other people?

Sleeping in a heated (or air conditioned) room?

Modern medical care when you're injured or ill?

We really have no idea what "the norm of natural" would be. And some things that are not "natural" are clearly beneficial.

  So is long distance running natural?

  Periodic fasting?
Yes, and yes[0]. In fact, the one competitive advantage in early man hunting game was endurance -- humans could outrun almost any game (including fast sprinters such as kudu) over long distances, partially because humans shed heat better.

[0] http://news.usc.edu/82959/diet-that-mimics-fasting-appears-t...

I tend to agree they are healthy and likely natural. There are people who dispute both (google "long distance running unnatural" or "long distance running unhealthy'). Our "natural" behaviors tend to be "just-so" stories, rather than rigorously proven benefits.

The point is, for many things, we aren't sure if they are natural, and many things we take as natural and healthy ("Three square meals a day!") may not be

With just about every recommendation for "healthy living" you can find scientific arguments on both sides.

There's no doubt personal variations within any given recommendation. The sweet spot should be a starting point, and from there you see if your genetic and gut bacteria profile fits the given study.

That said, I can't recall a study that concluded soda is good for you, yet a vast majority of US adults choose that path and stick with it.

One of the reasons they stick with it is everyone else sticks with it. There was a time smoking was normalized, to say nothing of cool. Then finally it was marginalized. Can the same happen with weight and obesity? Maybe. But to date it's extremely non-PC to even imply excess weight is bad.

I'm advocating shame. But allowing the unhealthy to become normalized isn't working either. Geez, the DoD declared it a threat to national security. Kneeling in unAmerican but being to big to fight is patriotic?

I can't get my head wrapped around that. I see no hope for things changing for the better anytime soon.

No idea? I'm not so sure that's true.

As for not natural but beneficial, can you give an example? Or three?

Off the top of my head; vaccines, vitamin pills, penicillin, and hip replacements.

Well. I think hip replacements are not natural. The other three are just "man made" versions of things that readily exist(ed).

But perhaps we have different definitions of natural :)

In addition to Godel_unicode's examples

Purified drinking water.

Mosquito nets

Sewage systems

Antiseptics in medical contexts

Washing hands after using the restroom

Lifting heavy things on a regular basis even though you don't have to.

To me, Aspartame is unnatural. In that context, mosquito nets, sewage system, etc. are natural.

Maybe we just have different definitions :) But to me, progress (i.e., human's reproducing existing patterns) doesn't necessarily equate to unnatural.


Doubt it. They didn't arrive at their opinions via a measured dispassionate analysis of the medical literature, so why would any of this affect them at all?

Society appears to be moving to a post-fact era, where opinions and feelings matter more than evidence and data.

Just like all those stubborn meat eaters ignoring the science that eating meat increases cancer risk.

In other news, fire burns.

In what way is it obvious that obesity leads to cancer?

i'll go out on a limb and agree with you. it's not "obvious" that obesity is linked to cancer unless you view the world through hindsight-glasses. skinny athletic people get cancer too.

it wasn't even "obvious" for most of the 20th century cigarettes gave you cancer. people have short memories.

a contemporary example: is it "obvious" right now that sugar gives you cancer? because to a lot of people it is blindingly, astoundingly obvious, and to some that sounds like conspiracy theory nonsense.

i don't understand this aversion to doing "obvious" science -- we have to do science to make things obvious, not the other way around.

Google « obesity cancer », you’ll find many. It’s just that I thought it was common knowledge by now..

It doesn't directly lead to cancer, it increases, to some extent, the risk of some kinds of cancer, which can be influenced by life-style choices, to evolve. (The title says "linked" in the sense of being correlated.) That's pretty much common knowledge.

putting more unhealthy things into your mouth causes cancer, pretty obvious

it's actually quite easy to consume a caloric surplus with only "healthy" foods. beans, steak avocado, nuts are all examples of "healthy" foods with high nutrient density and high caloric density.

I just noticed you slipped in steak https://www.nytimes.com/2015/10/27/health/report-links-some-...

If you overeat of a Standard American Diet you increase the risk of heart disease and cancer.

Higher body mass means a larger amount of tissues which can develop cancer.

I don’t know why the downvotes. Everything else being equal, more body tissues can only mean higher cancer incidence (even if the increase is small, I’m not saying it’s the main driver in the results reported).

A link between cancer incidence and height has also been reported in the past. There may be several factor at play (higher exposure to growth hormone, higher caloric intake) but it is not unreasonable to think that cell count is one of them. For things like skin cancer, it’s hard to justify that size doesn’t matter.

Yeah I had this thought too. It might be a gross oversimplification but uh it would make sense that someone who is 3 times as large may have 3 times the odds.... More research needed obviously.

Because like smoking it’s obviously unnatural to eat like crap and sit on the computer/couch/car all day. If not obvious then not surprising. Obesity is the epitome and result ohf an unhealthy lifestyle of no exercise and eating junk food.

Obesity is obviously unnatural and unhealthy and I still don't see how it is obviously linked to cancer.

Cell division is not perfect, each time there is a chance of error. This is why anything that results in a net increase in cell division will be linked to cancer.

Obesity means you have more cells than other people... to have more cells there must have been more cell divisions. The role of mitogenesis in cancer has been realized for many, many years[1], so I'm not sure why there is still any controversy about it.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC54830/

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