Why Are Thin People Not Fat?

Why Are Thin People Not Fat?

2009, Health  -   110 Comments
Ratings: 6.83/10 from 84 users.

Why Are Thin People Not Fat?The world is affected by an obesity epidemic, but why is it that not everyone is succumbing?

Medical science has been obsessed with this subject and is coming up with some unexpected answers. As it turns out, it is not all about exercise and diet.

At the center of this programme is a controversial overeating experiment that aims to identify exactly what it is about some people that makes it hard for them to bulk up.

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The Skinny White Mr. Motivator
2 years ago

TO ALL SKINNIES: Speaking as a skinny ass ectomorph though whos always struggled to gain mass, a vegan diet is prob the worst thing you could do, that is unless you had disposable income to afford added protein vegan foods... or the massive will power to constantly just eat nuts and dried fruit, which are again expensive if you want the healthy ones.

Personally for dude whos 6ft 2 and weighed 9 stone at my unhealthiest, I have tried to maintain a well rounded diet, but with the added extras of whole milk, peanut butter (ideally the healthy stuff) and as much dried fruit, eggs and nuts as I can stomach (not much at all).

Realistically I cannot afford to eat 6 meals a day as recommended to gain mass so these fillers (esp peanut butter and milk) are a godsend. I LOVE meat btw, but pork is def not a healthy one (though is cheapest) so try to only eat pork once or twice a week. Am starting to do one day a week with no meat also as Arnie recommends trying. I do push weights, stick to 3 main excercises, 3 sets, and bout 3 times a week. It is a struggle to keep the weight on still, as I have to eat something heavy every 2/3 hours and I am easily distracted by my work (selling songs) and hobby (making music) sometimes it can mean I starve myself stupidly and end up cutting weight unintentionally. But at my healthiest so far I now weigh 11.12 stone. Ideally want to get to 13 stone so I can break this body type, hate the fact everyone assumes I am skinny still, but I aint gonna walk around flexin with my top off to just to prove im not. So def still got a ways to go but once I get my income up a bit that should be easy enough from here on out.

Sugars not that bad as long as you moderate respectively. But diet drinks and no sugar squash with artificial sweeteners seem totally counter productive, not to mention can possibly cause brain cell death and a heap of other disorders...and they taste like shit. Better off with water, whole milk, and I always have glass of grape juice or pineapple juice with breakfast (Ive noticed if I dont keep this ritual up, the weight loss starts , very subtle, but it does begin to happen) SO GET DAT SUGAR IN YA AND BURN IT OFF WITH WEIGHTS!

BTW anyone on here body shaming people should be ashamed of themselves. You have no idea what its like in someone elses body, so stop making sweeping generalist statements about how fat people are lazy or skinny people are...lazy. Lol can you see the contradiction there?? Yes to change either body type takes huge will power (which some people just dont have) however there is also a lot of other factors to consider (medicine, medical conditions, genes, etc) Also nowadays everything boasts how healthy it is even though its quite often the opposite, a lot of people are just products of they environment and believe these products cannot legally lie to them. These people also believe the government has never lied about anything ever (despite numerous false flag invasions and the federal reserve which prove otherwise) Just think for yourself. Anything natural is prob healthy, anything mass produced by man is prob poisoning you for pure profits. This is why balance is key, we cannot all afford to eat natural foods 24/7 and even if we did we would never gain weight as most natural stuff has such low calories. Also theres so much misinformation out there now, you cant even google a damn thing without at least 2 skools of thought, means REAL TRUTH has gone the way of the dinosaurs, so use ur brain before it gets murked from aspartame n shit. Peace yall x

4 years ago

I know people who eat a lot, don't exercise much, yet stay thin. The people who commented here giving one answer fits all people are typical know-it-all pieces of ****. Each person is different and there are many factors that cause people to get fat but not all those factors apply to everyone.

4 years ago

"At the center of this programme is a controversial overeating experiment that aims to identify exactly what it is about some people that makes it hard for them to bulk up" - thing is you really don't have to bulk up at all.. Especially with the earlier mentioned obesity-epidemic.. The conclusion of the documentary is [SPOILER ALERT], that the genes are defining your body shape (however, body shape may be manipulated by your lifestyle due to certain genes being "activated" and processing a certain .. So why is there a constant pressure to serve a certain "goal weight"? No such thing exists. Accept who you are, and if you consider yourself "too skinny" then you haven't found self-acceptance yet..

Rei Quincy
5 years ago

The answer is your gut bacteria controls what cravings you have. I didn't even watch the video, but I am telling you anyway. If you have a microbiome because of your diet filled with meat, cheese, eggs, and dairy, then your 'bacterial brain' will make those choices for you, and then you have to use your real brain to resist, and that sucks. I know, because I yo-yo about 15lb back and forth when I put 'normal (American)' amounts of Meat/Dairy/Eggs into my diet. When I eat rice, veg, tofu, and sauces (which are also unhealthy, I'm sure), I'm fine, even when I also eat tonnes of sugar throughout. For my body, at least, it is 100% the animal products that cause problems. (But I'm sure I could loose more if I cut out sugar, too.) I'm currently on a high (123 lbs - healthy weight for me is like 105-107ish), and I'm always hungry all the time due to lack of fibre. WHAT ARE THESE CHOICES YOU ARE MAKING, ME?!

Jacky Montecinos
8 years ago

As a thin person for all my life I can definitely identify myself with the study people. It is what it is, it really is in the genes!

9 years ago

Because we don't constantly stuff our faces.

You're not breaking the laws of physics, fatties: if you're gaining weight, it means you consumed it.

Mass is NOT spontaneously generated within your body.

9 years ago

What a bunch of BS! Bigger people do not have bigger stomachs. Nor, do they crave more food! I was a thin person all my life. 67" and never over 135#, until i gained 75# in 6 months. I really knew something was wrong and found out I had Hoshimoto's thyroiditis. The thyroid meds are are a weak replacement at best. I still can't loose weight and my BP and Cholesterol have increased considerably, despite I'm nearly vegan and ingest scant amounts of animal products, and never any butter, cheese, or milk-fat of any kind. As far as craving more food; I only get hungry around once a day. This is a classic symptom of Hoshimoto's-low appetite. I've always been a nibbler, and the current studies show, I've the classic pre-disorder profile: thin female with history of low appetite. Also, here's a kicker; 1-10 adults have this disorder in the USA. I know, because I'm an RN and have done the research. So, just saying, you people don't know what you're talking about and let your fear and prejudice of fat people control your thoughts.

10 years ago

Bigger people have bigger stomachs - the bigger the stomach, the more calories you intake... And the more weight you put on. The more weight you put on, the bigger you get. The bigger you get, the more energy you need. The more energy you need, the more you need to eat. The more you need to eat, the bigger the stomach gets. The bigger the stomach, the more calories you intake...

10 years ago

People are so stupied its insulin cause of obesidy

10 years ago

Oh and we're now all on ketogenic diets, because we were born with heterozygous familial hypercholesterolaemia. That changed our lives lipid-wise. We eat fatty meat, cream, fatty fish, chicken with skin, duck, goose, almost zero carbs and we've just gone thinner, but with best lipid profiles ever in our lives. Doctors are astounded. Very easy life direction - we like our food now to boot.

10 years ago

I do think fat kids happen to parents who are obsessed with food, whether healthy food or not. The thing is not to make kids overly conscious of food, in my opinion. I remember taking my young toddler to a paediatrician coz he wouldn't eat and the goodly doc said: "so what's your problem?" he'll eat if his hungry (after ruling out anything else) - my son grew up as a thin person, like the rest of my family. We start cooking when we're hungry and then they'll sort of eat on the fly. I've noticed ppl going into intense discussions about food in front of their babes. I think don't do it.

10 years ago

What happened to their health statistics ? They didn't comment on that. Those who didn't gain weight, I suspect their cholesterol and blood pressure for example went up, so their risk of cardiovascular diseases increased.

Monica Rocha
11 years ago

this is in line with jon gabriel's way of losing weight...

roberto bertulfo
11 years ago

Do fat people actually eat more than the thin people per hour, per day, per week and so on...? Record their habit of physical movement, and frequency of eating and total it for the whole month, fat people actually take in more food compare it to thin people. (Fat people think that he equation for food is 1X1X1....=X, but 1+1+1...=X). The more you put into your mouth, the more you gonna get it. Fat people crave for food more times than the thin people.
Fat people when they see a lot of food they have a big appetite, while thin people when they see a lot of food, they are disgusted.

11 years ago

I allow for the idea that some people are genetically predisposed to weigh more or less, but the majority of people don't differ violently enough to escape the fact they will, with a healthy lifestyle sit within the 'healthy' bmi range...that's what averages mean.

And even if you don't sit in that category (like myself), when did regular exercise and a healthy diet cause anyone more problems long term?

An overweight person saying 'I cant lose weight - I'm genetically predisposed to being overweight' is like me saying the same about being underweight. Yet, I accept I can push into that 'healthy' bracket with a little more work. I CHOOSE not to exert the extra effort required to achieve that, so I don't whinge when (as happens almost daily) people comment on my being underweight.

The difference between my being underweight and -for eg- my friend who is overweight isn't in which end of the spectrum we sit in terms of weight, but in attitude.

The other day, I said she might benefit from directing her frustration about being overweight into going for a brisk walk, that it'd help her -in the long term- fight her negative feelings much as anything...and her reply was 'depression runs in my family, I cant escape it wherever I damn well walk'.

I'm bipolar and have been underweight my whole life despite having always had a very healthy lifestyle; I know well as anyone exercise and diet isn't going to 'cure' bipolar or change my body type.

The issue isn't genes or illness, it is attitude. my friend says a walk isn't likely to cure her weight problem or depression. I say walking isn't likely to make things worse, and may just alleviate my reactionary depression and improve my physical health...so lets do it.

As for 'fast food is addictive'...if that information is true it has an instrumental and positive use in identifying and then addressing the problem of people who are addicted and in preventing addiction more generally. But it seems all the 'genetically predisposed to being overweight', 'under active thyroid' and 'fast food is addictive' theories often only serve as excuses by people who are unwilling to accept responsibility for their lives and their bodies.

You are not fat because you have problems; you are fat because you won't address those problems...


11 years ago

The problem with ALL obesity research is that it's goal is not to find a solution, but to find another blockbuster drug that would have to be taken on everyday basis. That guarantees a total failure just like the "war on cancer".

Mike Staffieri
11 years ago

obesity is not a one factor thing...it's genetic and epigenetic...many fast foods...high salt/sugar/fat are addictive, spiking dopamine levels with opiate like after effects. They should measure Intestinal Alkaline Phospatase(fat busting enzyme) of the subjects and obese people. Take your probiotics and your "fat virus" will disappear

11 years ago

Thank F*@# for the Brits/Canuckidans and their socialist medical care system, because of this we can get REAL info from peer reviewed legit clinicians and scientists unlike in the States where big pharma either owns out right or has a controling interest in every medical school and controls the purse strings of almost every University level researcher's grants. The US is in decline because ignorance has been a boon to those who can profit from it and most Americans are too busy w/ the latest cell phone apps and/or reality TV programing.

K Styron
11 years ago

Pizza with MAYONNAISE?

11 years ago

I lost weight by just eating 1,200 calories and cycling for two hours a day. It worked for me. I'm still going under the knife to reshape my body to my ideal shape. I want to have a smaller waist than my hips. Unfortunately, my hips are narrow so there is no diet or exercise I could do to get the hourglass look I want. F*** everyone else I want to have the body of Dipannita Sharma. To me that's the perfect body shape I want for me.

11 years ago

The show was kinda boring but I kept watching until the popcorn ran out!!

11 years ago

I'm lucky enough to be one of these people. In high school everyone always asked me what diet I was on...I literally ate whatever I wanted and rarely exercised.

12 years ago

Very interesting. Thanks for posting this.

12 years ago

an excellent documentary! theories were proven. and now i understand why eventhough my sister & i eat the same amount of food everyday, she NEVER gets fat but I do. hehe. but this doesn't mean that i would stop my diet & exercise. it makes me feel healthy. ^-^

12 years ago

This is me all over, i can eat anythying... in actual fact, i might go and eat a massive cream donut now, and not feel guilty one bit... because my natural weight is already determined, i wont even have to worry about it!!! I think i might go and eat 7 actually. UNLUCKY FAT PEOPLE! Lets just hope i dont get the 'fat virus' lmao!

12 years ago

thinking burns calories. Iq may correlate to body fat.It would be interesting to test this theory with college students.

12 years ago


fasffeaf geamna
12 years ago

I didnt really like this movie mostly because I was a fat child myself and lost weight during my teens but now the weight is creeping back up on me.. I think it should point out the reasons for being fat or thin but it should also bring inspiration to fat people not hopelessness by suggesting ways to lose the weight and to tell us that were not bound by these childhood behaviors or genes

Gary V
12 years ago

Another superb, interesting & informative doc from the BBC Horizon team.

12 years ago

It's stupid... trying to fit all people in little categories. Every body is different. It doesn't matter what you look like as long as you're a happy, hard-working citizen. But even so, a person should never let themselves get TOO FAT or TOO THIN. We should all be fit ;)

12 years ago

How about measuring how many calories aren't absorbed by the body? There are calories in fecal matter so why is it that nobody has considered that maybe some bodies don't actually metabolize those calories?

12 years ago

I'm on part 5/7, and what I keep thinking of is "maybe the people who aren't gaining more fat were eating less grams of fat and/or sugar."
I dunno. I'm no doctor, but they should have tried to control that aspect, also.

12 years ago

Interesting doc... I would have liked to be among the participant to test how much weight I could really put on for a month. However there's only few issues in my case... I have severe case of hypoglycemia... whatever i eat gets burn so fast that when I was young I could eat a bag of sugar and be ready for another one two hours later. I also have a disgust for everything super greasy... fast food disgust me; no pizza, no hamburgers, I hate potatoes so no french fries, hotdog (unless they are homemade) hasn't got desert for the last 15 years, and I'm super lactose intolerant.

Well I guess I wouldn't have been selected LOL.

12 years ago

Wow Martin Wong must be a long lost cousin of mine or something because I'm also like him (except female and chinese-american). I used to be miserable growing up because I would eat a huge amount of calories in a desperate attempt to gain weight/feminine curves and never did. But I was always very athletic and physically strong so maybe the reason my weight gain could be measured by the scale but not visible to the eyes was because I had an increase in muscle mass. Now that I'm at the ripe old age of 26, I can no longer eat the way i did without gaining weight. the good news is, the weight that I've gained is just the amount I want because I FINALLY have boobs now!

there definitely is a genetic component in resistance to weight gain because the vast majority of my family are slim to normal. None can be categorized as even remotely near obese.

12 years ago

@Lainy- his wife, a vegan cheif, put him on a vegan diet to lose the weight

12 years ago

lol at u fat fuks

12 years ago

Im skinny, 160 pounds... why is it such a bitch to gain wieght!? :( I wann be jacked and slamming girls by the day!

13 years ago

i can tell you that not all asians are like that , im asian and its like an everyday battle for me to not gain weight . although my brother cant gain a thing at all no matter how hard he tries ,

Phil Atio
13 years ago

My weight loss secret=meat + vegetables/fruits + candy. No carb diet and I lose weight like a monkey.

13 years ago

this guys should've smoke some pot to be able to finish eating all that.

13 years ago

Well Your body digests calories from chips differently then calories from apples. You don't see a diabetic refuesing to eat an apple because his/her sugar is high do you? no.
So to everyone who is saying "excess calories are excess calories" that may be somewhat true,but not every calorie is concidered "equal" in the human body.
oh and sorry for any spelling mistakes it is not my strong point lol

13 years ago

excess calories are excess calories, whether it's 500 calories worth of broccoli or 500 calories worth of potato chips.

13 years ago

You tell em Karen!

13 years ago

Continuing on, there's no uniformity of what they're eating or how much they're exercising. They're Also not considering how much the subjects were eating before hand. Perhaps for one person, their calorie target is three times their maintenance diet, where for someone else it's double, but that person used to run every day. How on earth can they isolate some 'obesity immunity' when there is no continuity in the actions of the(incredibly small) sample group, and no consideration of their starting points? Good grief, they're not even being photographed in the same clothes. What sort of scientific study photographs bodies in street clothes? Idiocy.

13 years ago

This is possibly the stupidest documentary I've ever seen. The very fact that they're being constricted from their normal amount of exercise creates a huge additional variable. The fact that they're suddenly eating not just more, but a completely different diet because they're responsible for figuring out on their own what to eat to boost their caloric intake is another enormous variable. Would an extra dozen eggs have the same effect as a belgian chocolate shake?

Charles B.
13 years ago

Wow! Boy am I depressed now. So, do I have a "chicken virus" or am I just genetically predisposed to being overweight?

I thought it sad that when fat people loose weight their brains make them feel like they are constantly starving until they gain the weight back.

I was just born in the wrong time period I guess. My ancestors had long lives and made it through the depression and starvation (seriously) just fine, so my ars if fat now, and hopelessly so. Thanks, gramps!

I'm fat but my wife is slim. She eat rice by the plates full; and chocolate. My son (age 3) is slim, and it's sooooo hard to get him to eat anything, but my daughter (17 months), even as we speek (litterally) has fork in hand and is on the kitchen table with bread and jam.

We're raised both the same, but my boy is obviously genetically taking after my wife, but I sure hope my lovely little girl doesn't follow too much in my foot steps. She trying to feed me bread and jam now! LOL :-)

P.S. The boy hates bread and jam and has eaten none today despite it's easy availability.

13 years ago

This documentary sounds particularly clueless with regard to why people gain weight. They need to read Gary Taubs "Good Calories, Bad Calories".

doc watcher
13 years ago

I was shocked to find out the luck out dude of Asian descent put on muscle instead of fat with the excess calories.

seems to defy logic. would then he be able to eat his way into a body building competition without lifting?

13 years ago

Karen I often have problems with streaming.... When i do I put off viewing you tube until all the yankies are snuggly in bed.

Lainy regarding Morgan spurlock i seem to remember it took him a whole year to recover form his McDonalds experiment. I have to ask btw are you Loraine Read?

13 years ago

Your "natural" weight is variable accordingly to age related metabolism. I was a skinny fricker till about 35 - used to be able to eat anything drink anything - pig out generally. Then I ballooned. Even so I can still lose weight very easily - I lost 6 stone last year when I put a bit of effort into it. I have my beer belly back now however.