Why Do Some People Never Get Fat? Scientists May Have the Answer

By Boonsri Dickinson | March 17, 2009 11:19 am

burgerweb.jpgRemember the guy from Super Size Me who ate about 23,000 Bic Macs and never got fat? Ever wonder how he did it? Turns out he may have been born without the “fat enzyme.”

The enzyme MGAT2 is found in the intestines and determines the fate of our food by regulating how it is metabolized: It either makes fat go straight to your waistline, or converts it into energy. Scientists in California have discovered that when mice are missing the gene for MGAT2, they can eat whatever they want and never have to worry about getting fat.

The University of California at San Francisco knocked out the gene in experimental mice to see how their bodies grew after feeding them different diets. When the normal and experimental mice were fed a diet low in fat, both sets of mice grew the same way. But when the mice were eating a 60 percent fat diet (i.e., a typical American diet), the experimental mice weighed 40 percent less and had 50 percent less fat than the normal mice.

Not only does decreasing MGAT activity in mice reduce their chances of packing on the pounds, it also prevents them from developing other obesity-related problems such as fatty livers and glucose intolerance. While the researchers are unsure of precisely how the experimental mice kept the weight off, they think that when the mice are missing the MGAT2 enzyme, their body ultimately doesn’t store or use the fat.

Still, don’t go on a Big Mac binge just yet: Until scientist can figure out how to manipulate this gene to create the magic skinny pill, we will continue to metabolize food like we did when we were hunters and gathers.

Related Content:
DISCOVER: 20 Things You Didn’t Know About Fat
DISCOVER: Killer Fat
DISCOVER: Fat Is Not The Enemy

Image: flickr/ livinlowcarbman

MORE ABOUT: fat, genetics, McDonalds
  • http://www.brianlang.ca Brian Lang

    Better to just eat real food instead of processed crap.

  • Pingback: The Key to being Slim, Fit and Healthy « Bryce Redford - The Bodymind Coach()

  • danthemanhan

    How about a gene to gain wait now? seriously, weighing the same as i did when I was in grade 10 in high school is not cool.

    • Rea

      For women is sure is!!!

  • You are all retarded

    The guy from Supersize me DID get fat. He almost died. You are all stupid fucks. FAIL.

  • They’re not retarded: you didn’t read the article

    Not >THE< guy who did Supersize Me, one of the people interviewed in the film, Don Gorske, is who ate 23,000 burgers over the years and hasn't gotten fat.

  • YouRang

    Well yeah the guy who ate the 23,000 did it over more than 30 years! That comes out to about 2 a day; and some burgers are bigger than others, so 2 a day can be less than the daily allotment of 5 oz a day.

  • NervaVels

    I’m one of those people who can eat lots and cannot store fat. It is rather strange. I’ve only gained 20 lbs within the last 25 years, despite having kids. I would love to be able to pass that ability on to my friends who struggle with weight problems despite being healthy eaters. I hope this leads to better methods of weight management!

    I’m 44 years old, and weight 100lbs at 19. I don’t care what the popular definition of attractive is, skinny is gross and I always wanted curves…

  • Micky

    Hey…LOOK Here!! I Have The Answer To Everyones weight problem. I’m serious. You know that skinny & overweight people have something in common? Well, all humans have bacteria in their stomach & intestines which basically function to digest their food. & fatty, high caloric food the baxteria like best. Now, i have never had a serious weight problem, but like all teens & young adults, I tended to be a little bit paraniod about my weight. Anyway, after yrs of flirting with Anorexia & then bulimia, i came upon the bacteria which literally changed my life for the better. I have tried various bacteria pills over the yrs, & recomend a Probiotic pills to my readers. This means the bacteria are protected from the stomaxh acids. Also, i take the low number of bacteria, say 3.4 to 5 billion per pill. This’s mozt cost effective stategy. And i did take 6 to 10 pills a day. But i have recently dropped to two a day. And my weight no longer concerns me. I eat whatever I want, when ever. But strangely, I have noticed that now that I can eat all I want, I no longer want the bad foods. Micky (Mic308@aol.com)

    • Llllll

      ….i think we skinny people dont need a way to stay even more skinnyer -.-

    • R.Hedtfeld

      Erm… people don’t have bacteria in their stomach. Except for people with gastritis or food poisoning, that is :)

      In a healthy human without gastrointestinal diseases, bacteria are only found in the large intestine. Food is first dissolved in the stomach acid (along with bacteria that might be present in the food), then the nutrients are absorbed by the lining of the small intestine.

      By the time the food reaches the large intestine, most nutrients have already been extracted, completely without the help of bacteria. Only hard-to-digest components such as cellulose are eventually digested by bacteria in the large intestine (the so-called gut flora). 


    In ma side think fat depends on the nature of the family you come from.All of ma family member are thin and I believe never become fat

  • ScienceBoy

    Something changes over time. Up until I was about age 30, I WAS that guy who could eat whatever I wanted, as much as I wanted, and never gained any weight. I struggled to try to gain any weight. In high school I was 6’4″ and 155 pounds. Then, shortly after my kids were born, I started gaining weight slowly. I ate less and exercised more, but nothing seemed to stop gaining 2 to 3 pounds a year over the next 20 years. It’s a family pattern I see with my siblings, mother, and other relatives. We end up old people with skinny bodies and fat bellies and diabetes.

    It’s probably too late for those of us alive today. Some things just don’t show up in a lab test. After you have something affecting millions of people for 40 or 50 years, then maybe it becomes apparent that there is a long term cumulative effect from something in the food, or water, or air, or pills, etc. Some research statistics suggest that obesity is spreading like a contagious disease. Well, maybe it is, and we just haven’t identified the cause yet.

  • ScienceBoy

    I love the contrast in the headlines to which this article has links. Both “Killer Fat” and “Fat is not the enemy” appear together.

    Science marches onward. Good science corrects its mistakes eventually. For example, people had been told forever that stomach ulcers were caused by stress and spicy foods and told to take antacids and eat bland diets. Then one day, scientists finally discovered the REAL answer. The problem was heliobacter pylori and you could cure ulcers by killing the germ that lived where no one previously thought a germ could survive.

  • Tom

    I never get weight put on :(
    I see as a curse more than a good thing D: I eat and eat but I never get bigger :(

  • jye bannister

    well now i no why some people dont gain wait but i am one of them people and i am a footballer and am far far too skinny so if i one of these people that cant gain fat wat am i ment to do because getting bowled over by the bigger players everyweek aint much fun plz help p.s i eat a truck load each day but it wnt do nothing

  • JT

    Alright, here’s a thought. How many of these people who can’t gain weight have parasites? I’ll bet there’s a large number of them who actually have intestinal parasites and/or worms that “help” keep them thin. I saw an autopsy a number of years ago of a young man who was thin, muscular, and had a 6-foot tape worm in his gut. I’ll bet he was one of those guys who could eat anything and never gain a pound.

    In the same way I agree with the idea that bacteria in the digestive track is closely related to the ability to control weight. I’d bet that the processed junk that comes from fast “food” restaurants kills off bacteria by the billions and the lack of more natural unprocessed foods fails to reintroduce beneficial bacteria. Similarly, heavy use of antibiotics (especially among children) has a similar effect in killing beneficial bacteria.

    Could it be that in looking for the answer to weight loss we are so focused on humans as isolated organisms that we’re missing the possibility that other organisms may be even more important than genes?

  • Sutebe

    Hmm, that would make sense for me. Either that or I have a tape worm, which is what the majority of my friends think.

  • Rachel

    I bet thats what is with me. I eat alot (I would say at least) and I dont gain anything.

  • msconsistent

    This makes sense. When I was 14, I hit my full height 5’4″ and my permanent weight 120 lbs. I’m almost 47, and am exactly the same size.. (Pregnancies were an exception.) Doesn’t matter if I’m sedentary or in a routine where I run 3 miles every other day. Doesn’t matter whether I’m eating salads or Mac & Cheese. My body can’t see the scale, but somehow it sets itself to 120 lbs and that was that.

  • Pingback: Want to Up Your Chances of Dying From Swine Flu? Be Obese | Discoblog | Discover Magazine()

  • HeadShakingatNo4

    Wow… could the person in post number 4 sound anymore immature? I mean seriously… is it possible? I’m thinking the answer is “no.”

    You could always go for a Vegetarian or Vegan lifestyle. Its hard to switch, but it seems the payoff is worth it.

    Read a book that recently scared me to go Vegan called “Skinny B****” for the ladies, or “Skinny Bast***” for the guys… seriously, the books do exist.

    Check out your local bookstore, it is worth the read.

  • jb128

    It really is a great life.

  • http://www.losefatbuildmusclefast.com Lose Fat Build Muscle

    I would wait for this pill MGAT and I would definitely try one. For now, I’ll stick to proven methods, mindset, diet, exercise.

  • Pingback: Why Do Some People Never Get Fat? Scientists May Have The Answer. - Myprotein Forum()

  • http://momingle.com momingle

    Does the gene have any other purpose? If we take it out, there maybe some other problem that we didn’t expect.

  • http://www.mychinesefortune.com fortune cookies

    Girl eats too much sweet take up two seats.

  • rosy

    damn…gotta get those burgers in me noww

  • deed

    So how in the world do you get fatter? I’m 19 years old guy and only weights 120lbs. Eating does not work for me :(

  • http://www.Muwasalat.com Muwasalat.com

    There was some documentary about FAT VIRUS like it’s like a disease that spreads. It was on National Geographic.

    They were saying that it was an epidemic.

  • http://www.eightforums.com Gates

    Advancement like this is what science is all about! interesting how genetics build us into what we are.

  • Jilly

    but processed crap tastes oh so good 😉

  • Patrick

    It seems to be that many readers misunderstood the article. MGAT2 *CAUSES* weight gain, not removes it. Any therapy will either counteract MGAT or be forced somehow to remove it from the body – a harrowing and probably impossible feat. So don’t “wait for this pill MGAT”, because there isn’t going to be any.

  • Pingback: Why Do Some People Never Get Fat? Scientists May Have the Answer | Ethiopian News()

  • Pingback: Disabling ‘fat enzyme’ lets you eat anything and never get flabby | Daily Contributor()

  • Skinny vegetarian (not a bitch)

    It’s quite normal for teens not to gain weight even though they eat burgers and candy and all that. The reason is that it takes energy to grow. Young people just use a whole lot more energy whilst they’re bodies are growing and thus don’t gain weight that easily. I know loads of women who were thin when they were teenagers but suddenly gained during their 20s. It happens to most people. I ate junk food all the time in my teens, candy, sugary stuff, snacking all the time and never gained weight even though I wasn’t stick think, I was still normal weight despite all that junk. If I was to eat that way NOW when I’m in my late 20s, I would literally bloat like a balloon. I’ve managed to stay the same size all these years but today I have to watch what I eat.

    Also it’s quite deceiving to think that if you see a skinny person eating a hamburger that they must be one of those lucky ones who never gain weight. WRONG. It could just be that the skinny person eats very lightly when you’re not there to watch. Whenever I go out with my mates and we go to a restaurant, I always order something delicious (& fattening) plus always a desert. My mates go “Oooh, how can you like that and still be so skinny!? It’s so unfair!!”. No, it’s not unfair. I exercise regularly, I don’t snack, I don’t even eat breakfast, I don’t consume large amounts of alcohol, etc. That’s my secret to being skinny and still being to allow myself an odd treat every now & then. If it’s a special night out at nice restaurant I sure as hell not going to order salad, when I can eat salad like every normal day and then treat myself at these kinds of special occasions.

  • http://www.escapefromobesity.blogspot.com Lyn

    Interesting, but regardless of what genes or enzymes we have, we have something those mice don’t: the ability to CHOOSE what we eat and how much we exercise, and thus, the ability to change our weight… even if it takes more effort for some of us than others.

  • Erik

    Cool! anted to download it by means of http://filesmixx.com/ – one of rapidshare search engines, but failed to find. Is it available at some other resource???

  • http://www.the-anti-diet.com Andrea Glowstick

    You wont believe me, I am down 6 pant sizes and 38 pounds in 11 weeks! Read books about a diet plan to manage healthy weight loss ! Take the plunge and feel the difference.

  • Pingback: Fat or Flat? « ECSmith()

  • guest

    dump the fat? (may cause anal leakage)

  • anonymous

    im 5 feet 2 and weight 80 pounds
    and i eat a lot

  • hamma

    am 25 years oldbut i look 15 because am so small.i eat like a machine but never grow.am ready to do anything just to get fat and bigger.

  • http://discovermagazine.com Catherine

    I’ll tell you why I don’t get fat, I don’t overeat & I don’t use food for emotional reasons. I don’t deprive myself either, I eat icecream everyday, just not the whole carton.

  • Pingback: New Theory: Plastic Can Make You Fat? | Discoblog | Discover Magazine()

  • Skinny Girl Can’t Digest Fat

    I don’t really know why, my whole family is full of thin women. My mother, my sister, and I can’t digest large amounts of fat. My dad was convinced that I was lactose intolerant, like him, but I could still drink fat free milk, Breyer’s Ice Cream in reasonable amounts, I could still have small quantities of dairy products.

    In middle school, I would eat McDonalds twice a week and I would get so sick. I would get sick when I would overindulge on ice cream or drink milk with a higher fat content. I would get sick from eating fried foods or cheesy foods like pizza or lasagna. At one point it was normal for my mother, my sister, or me to take up the bathroom for long periods of time. We tried using Tums or Zantac 75, but after a while I couldn’t deal with the stomach issues anymore. It was getting in the way of my life and I was so skinny. I would get frequently questioned by teachers, doctors, and peers if I had an eating disorder. I went into ninth grade with a weight of 85 pounds and I was about 5′ 3.”

    I’ve stopped any kind of medication and I now monitor how much fat I eat (which is not much). I drink weight gain drinks with Carnation Instant breakfast and fat free milk, I eat tuna, pastas, whole grain breads, all natural juices to get vitamins, red meats for protein with little fat, poultry, cereals, and tons of other things. I’ve been trying to gain weight and it is a very slow process. If I miss breakfast, I’ll lose 2 – 3 pounds. If I don’t eat enough within a ten hour period, I’ll get super shaky and dizzy. I’m 19 years old and I weigh 111.5 pounds and I’m 5′ 8″.

    My sister and my mother have not learned. My sister sticks to a cheap college diet and ends up being sick for weeks at a time. My mother still continues to eat bad (and drinking coffee makes it worse), she eats the cheap butter with canola oil substitute (which is a very unhealthy cheap oil) and she has only gained weight from the medications she’s on and even then she’s only gained weight around her middle and not very much at that. I’ve figured out that my body burns calories fast and drinking coffee or soda just makes it worse. Eating processed food also gives me stomach aches as well and eating anything with canola oil in it or putting anything with canola oil on my skin makes me break out in hives. Perhaps my family has a sensitivity to unhealthy things? My doctor doesn’t think I have a hyperthyroid condition because I may not be able to gain lots of weight, but I don’t lose it too fast and my hair isn’t falling out.

    I just feel perfectly normal besides being super skinny. I’m not unhealthy skinny, so you can’t see ribs protruding or anything, but I just want to look normal. I was actually searching the internet for recipes that could help me gain weight and eat healthy and get all my vitamins, but it turns out not a lot of people want to gain weight and all they really say is eat a lot of calories and pray.

    P.S. I’m pretty sure I don’t have a parasite either, because they generally take all the nutrition from your food and you end up actually looking unhealthy. And I’m pretty sure I’m getting all the nutrition from my food and I don’t have any dark circles under my eyes, I just can’t digest a lot of fats. : )

    -Skinny Girl

  • Jess

    i have always been skinny its really annoying when people just asume you as anorexic or belimic when i have 4 meals a day and some snacks. i wont gain weight and i wish i would because some girls think being fat is bad but being super skinny is as bad. i need a sollution to this.somebody help!

    • http://www.facebook.com/milo.pu Milo Pu

      oh yeah , i have a exactly problem as you do.have you find out some solution of how to gain some fat?

  • stupid brother

    ok i just found the problem with my brother at first i thought he had a tape worm but he has this very unfair gene……..ugh! i try and try but i never lose weight gosh blah! i have this major obssesion with my brother how im not skinny and they are. all they do is eat and eat and have no excersie and also sleep like theres no tommorow. ive been going to the gym since i was 12 and now im 14, tall, over weight, and jealous how im not perfect. but theres a brighter side, im starting softball tommorow so i guess im starting a ” knew me”.?! WHAT A WAY TO SHUVE IT IN MY FACE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!>_<

  • CountryBoy

    Boo Hoo Hoo. I’m sick of all you fairy’s on here complaining about “not being able to gain weight”. How about you think about the other side of the coin, people who gain weight very easy and are therefore more prone to obesity related diseases. Suck it up people, if you want to get big hit the weights or shutup.

    • Indy

      how rude of you. everyone is self conscious.. let them be!

  • Sarah

    I eat pretty normally (not too much but not too little) and weigh 120 pounds. It’s what you put into your body. Eat healthily… what am I missing about everyone’s weight struggle?

  • Gorki

    Try the following blog for some answers.
    Still fresh but looks like promising. Worth checking.

  • jiggly snapple

    Let’s be honest: our genes determine our body types. I know this information will disturb the arrogant jocks who wish to judge the cellulite on a young woman’s body from ten feet away, or tell a random stranger to put down the pork pie and jump on a treadmill, but genes and environment determine your real body type and the outcome of any program you undertake.

    A relative of mine eats junk food at every meal – never exercises – and he weighs 120 pounds. Granted I checked his calories one day and they can get quite low, so maybe it’s not genetics as much as zoning out in front of the computer and forgetting to eat.

    I had two roommates in college – between 5 ‘ 3 ” and 5 ‘ 6 “. Both in the 80 – pound range. One picked at food and never ate. The other one ate a lot, whenever she wanted. Again, individual genetics at play.

    And then there’s me : little fatty on a mission, chubby for so so long. I can run 5 miles in a stretch – and I exercise for an hour several days a week. My caloric intake is currently the average intake of a 4-year-old – 1400 calories on activity days, 1220 on rest days. I have the precision of calorie counting down to a science – use formulas all the time to insure a deficit each day. And guess what ? Gained weight the first week. Now at a second plateau. So for me at least it’s an uphill battle. I’ll keep exercising and eating less to prevent weight gain, but there’s no svelte figure in my future. Fortunately I am not able to get super huge – really, even if I try to eat as much as I can I simply cannot become morbidly obese, ever – but neither am I thin enough to pass for – well – thin.

    Since we’re all different let’s just try to be hopeful and accepting of one another. Don’t automatically assume that a fatty is negligent or a thin person has to work on their figure. Maybe at extremes.

    Endomorph, Ectomorph, Mesomorph. The crap’s down to a science.

  • phelokazi

    when i eat a lot i still don’t get fat what should i eat to become fat

  • http://www.ourko.net Chef

    I have to say, the beefmeat on that burger looks a little dry.

  • slimboy

    some times i feel like, my body wasted food,, no matter how i eat i do not gain weight, i’ll soon get to 30 but my body weight is same as 1o yrs ago,some times i feel its our family gene cos our parents are skinny n small in size, but yet i have some siblings that are fast gaining weight tho i still have some other siblings that are as skinny as i am,,honestly i really need help on how to gain some weight,,i really feel bad each time some one says ” u are looking skinny”.i believe life would a lil bit more comfortable for me i could increase in body size, i’ll welcome advice from any one who really want to help

  • DaijaS.P.

    im 13 and i eat a lot for my age. yet i dont seem to gain any weight. my friends say that i is okay but they can fit into geans correctly and i cant! i want to wear that right size clothes and if i were a little shorter that could happen…
    just please some one friend a cure!!! please

  • carlos

    i never get fat n i love to eat i eat alot?

  • Wizzy

    I am verry tall nd skinny. . Buh my parents are all pot bellied nd fat. Im 19 yea$ nd verry tall. . . My friends say i’l get fat with time. . .i kind of believe them buh,i just cant wait 4 dat time. . . Its just like a lifetime to me. So i guess i’l start eating ma four square meals. . . And burgers nd pizzas inbetween. . . Then attend church more often, while waiting 4 scientists to conjure up a fatting drug or somtin. . . Nd i am so upset abt losing fat being more of a problem than gaining it. Its so so annoying. . . .
    . . ,Tinny

  • Andrew

    The people that say genes are to blame for their weight, they are seriously just looking for an excuse. My parents are both chubby, my sisters chubby, and I used to be chubby. That’s because we all ate the same food. We had the same lasagna for dinner, and the same cinnamon buns for breakfast.I started a rigorous work out routine when I was 11 so people wouldn’t make fun of me. Now I’m 15, and probably the fittest kid in my grade, complete with Greek statue proportions.

  • ryann

    i am 17, i am skinny.. i never get fat even if i do nothing and eat all day.. i don’t know if it’s a good thing or a bad thing.. but whatever.. i don’t really care about my weight..

  • prince

    some already may have the answer , as mgat2 is a enzyme like estrogen
    sure we have find foods that block estrogen and also other enzyme testosterone which decreases
    a produt called cla from cow may have this cure
    to inhibit mgat2

  • Mike

    I am sure genetics plays a role, since some do not get fat, despite a sedentary lifestyle and poor diet. But that is the exception. The reason most trim people are trim is that they have an active lifestyle, choosing to take walks, garden around the house, jog, swim, etc every single day, even when on vacation! And the reason most are fat is because they sit on their butts, day after day. The modern fast food diet only accelerates the process. Even so, people with very physical jobs (construction, landscaping, etc) are rarely fat even though their diets incorporate a lot of fast foods and fattening foods. See my blog post on this very subject at http://www.sciaticabackpainrelief.com/health/diets/people-fat/

  • http://wwwblogsdiscover.com rashid

    i was wieght135 pounds when i was 19 . now i am 27 years old and still 135 and i still looke like i am 19 .i think i still be like that for the rest of my life .if some body have any solution plz tell me.

  • Carlesme

    OMG this is how I am. I’m 14 and have weighed anywhere between 100-110 pounds for the last two years. I can eat all I want and I never gain any weight, and if I do it’s gone by the next day. It’s how I’ve always been. I don’t even exercise a ton. I love it 😀 You guys are jealous.

  • http://www.gmail.com omkar

    hello,i am 16 years old. i eat a lot but could not get fat. i am very thin.i want to become fat.please help me

  • http://www.deviledegg.org/ Deviled Egg

    I wish I had a problem of always being skinny.

  • Jenna

    This is how I am too!! :) I eat a lot but never get fat, at all!!

  • Jim

    I’m not trying to be an showoff on here. I’m 58 years old. My weight is 173, waist 32 in. BMI index is 23.2. Never been a gym person. I am active all time. I eat as much as I want, when I want and don’t gain a thing. All my life I’ve been this way. That said, I look at food in a different way than most. I don’t run to food for comfort. Just opposite, food is the last thing I want when I’m upset. I eat only when I’m hungry. Once or twice a day. Not by a clock telling me it’s lunch or dinner time. Thats been at odd hours sometimes. If I’m not hungry, I’m not hungry. Don’t try to feed me. I have a couple of ex’s that upset with me for that. I make up more than enough in one meal for what I didn’t eat in three meals. I’ll order a 16 in. pizza, then ask you what do you want? I don’t recommend this life style to anyone. It wasn’t plan by me. It just happen. This gene for MGAT2 enzyme mustn’t be anywhere in me. I hope this or some kind of other gene therapy is the answer for a lot of people.

  • sam

    Well….i literally hog myself but am veryyyy veryy thin
    its in a persons metabolism…some people just digest food fast. So some times even thin people might eat a lot but dont put on any weight
    Its in each of our structures and we should all be happy how we are, regardless of what others say
    love yourself man

  • john

    What bull. The guy eating big macs also only had 2 maybe 3 per day.. that’s what 1200 to 1800 caps a day? Caps I caps out. That’s not a lot there

  • asdf

    i gain wait when i look at anything sugary or startchy. period. i can eat a truckload of cheese and meat and stay thin but once i start adding pasta and bread i’m toast (no pun intended.)

  • bodydashi

    Why are some people overweight and some people skinny? the big factor is: fast metabolism and slow metabolism!

    Many factors effect the speed of metabolism,including:

    1. Environment:
    for example, if you live in a friendly and happy family or country, you are more relaxed, metabolism will slow down, it is easy for you to gain weight.
    If you are born in a troubled family or country,your metabolism will be fast.

    2. Genetics/personality:
    for example, some people are calm and laid-back naturally, this makes them more relaxed, thus slow down metabolism,they gain weight easily;
    Some people are born to be aggressive,active,sensitive,perfectionism,ambitious and alert, they change their moods easily,this makes their metabolism fast, it is not easy for them to gain weight,no matter how hard they eat.

    some people hardly think, they are “indifferent” to things, some may call them “stupid people”, their metabolism is extremely slow,they get fat easily and more likely than not,heath is compromised.
    While some people think a lot,a small matter will cause him to think a lot,they can detect any nuances and small changes,they never stop thinking, how to do this,how to do that,why this,why that….their metabolism is very fast.
    Lots of cases can prove this: for example,one skinny man suddenly became very large and fat after a head injury which caused him to become a retarded person.when your brain is dead and insensitive to any social matters,you are literally an animal, your metabolism is slow to minimal, you will get very fat if fed regularly.

    People with strong libido (high Testosterone)have very fast metabolism,those with “relaxed” libido (that is,low libido) have very slow metabolism.

    People who live under constant pressure have fast metabolism,those without pressure have slow metabolism.
    Of course pressure can be also linked with environment,genetics, personality and libido. For example,same problem,some may think it a big pressure, some don’t feel pressure at all.

    Now let’s get to some myth that some people still believe:

    1. Myth one: Eat more you will gain weight.
    This is not necessarily so, if your metabolism is fast, no matter how hard you eat, you will never gain that much.
    If you have slow metabolism, even you eat a little,you still gain weight;Actually many fat people eat much less than skinny ones. The key is metabolism.
    Several experiments have proved that this myth is wrong.

    2. Myth two: some people overweight and some people skinny is because different digestion and absorption of your food.
    overweight people have good digestion and absorption,while skinnies don’t.
    At a glance, you may think it makes sense, but after a second thought, you will realize,this is incorrect.

    Many skinny people eat a lot, if they have bad digestion and absorption, how come they have so good appetite?
    Actually lots of people with stomach and intestine problem (poor digestion) still get overweight.

    To sum up, Why are some people overweight and some people skinny? the big factor and the invisible hand is: fast metabolism and slow metabolism!

    In fast metabolism mode, you burn your energy faster than intake, in slow metabolism mode,it is opposite.

    There is one article in BBC website mentioning that one experiment showed it is not due to metabolism, it is a hoax.

  • creizzy chikka

    i think this is weird because if you eat alot of course you may get fat but i mean a ( fat enzyme ) im still wondering ! ! !

  • EP

    I am a 5’10” male (age 22 1/2) that weighs 115 to 120 pounds (some of it is from eating a lot of grains).

    There are people with weight problems in my family, but for some reason, I was not one of them. The differences between others and myself is that I am always moving, never wanting to sit down or stay in one place. My intestines become bloated if I stay in one place…but if I do eat less, I tend to become lazy and rather depressed. Grains and sugary foods help me, peanut butter, seeds, cheese, and thick fruits and starchy vegetables also do well in my stomach. Meat is not that great, but when it comes with starch, I eat more than most at that very moment.

    When I was not eating healthy, the only noticeable problems would be a little acne and bodily weakness, but I always had little fat content. My diet radically changed for mental (nervous system) reasons (I had meningitis and many other little problems).

    My weight has never gone over 125, and when it did get there, it went back quickly. If I did store fat the way many people do , I would probably not be able to do the things I enjoy doing…when I sit down and try to do something more sedentary, my body has trouble accepting it.

    I also need more “fat”, being that my skin gets dry and my scalp has psoriasis (which has been controlled to an allowable extent.) Of course, that type of fat is not what makes us fat.

    I did try cutting out sugar and even grains, but it made me feel miserable. In fact, I felt better with more (I do not eat white sugar/bread or food that is mostly sugar though [like candy], nor fast food and mostly no processed food). I tried being fruitarian, but I was always binge eating on bread, bread, potatoes, and bread.

    Luckily, I am not bony.

  • Jessica

    Most people who are thin just don’t eat very much on average so pigging out every once and a while doesn’t affect them. I have never met any one who was thin although they constantly ate way over a good calorie amount. I used to be jeolous of a super skinny girl i knew because every time i was around her she would eat tons of brownies and tons of unhealthy and fattening foods but then her boyfriend (my boyfriends brother) told me she always forgets to eat and sometimes passes out from it. Another time i asked an older woman how she stays thin and she said she is just really lucky but had eaten a salad for lunch and just came back from playing tennis…people stay thin and healthy throughout life by making it a life style not a miserable one week a month diet. by staying active and eating healthy and in reasonable amounts for most of the time an occasional slip up or bad food day wont hurt you. Sometimes thin people even think they can’t gain weight but it isnt because they just “cant” every one gains and loses weight differently but for people who are really thin over eating can be hard. my extremely thin friends are trying to gain weight so they will go to mcdonalds and pig out or eat tons of junk but still occasionaly forget to even eat. For really thin people gaining weight is almost as hard as losing it for an overweight person. Genes or body make up do not have a very large roll in what someone weighs. every starving person in ethiopia do not seem to have Genetic or hormonal tendencies to weight gain. Maintaining a healthy weight takes gradual work to make it part of your life and a lot of patients but in the end will be the best decision ever made.

  • JohnnyNunez1

    No wonder I eat so many times and I never even gain a pound but my mother eats only a couple of food and she gains 10 pounds I feel bad for her that she can’t eat the things she wants.

  • Janerammell

    Being a person who has been both fat and skinny in my lifetime. As well as having had kids, I can tell you this. It is just this simple: fat people are fat because they consume more calories than they burn off. And skinny people eat less calories than fat people. There is no such thing as “having a faster metabolism.” or having a “fat gene.” Live with a fat person, live with a skinny person. It is calories consumed over the years that is what matters. If you track how much a fat person eats compared to how much a skinny person eats over an entire year, the fat person eats more. It is just that simple. Skinny people have smaller appetites than fat people. Fat cells release a hormone which stimulates hunger, that is one of the main reasons why fat people eat more than skinny people. Skinny people have less fat cells than fat people.

    • guest1

      I’ve always had a small appetite and rarely pig out and I’m still overweight.. 

  • Slightly Concerned

    Genes play a role but that only affects less than 2% to 4% of the entire population. For the rest or 96% to 98% of the population, it’s just the simple fact that you are what you eat.

  • maddie

    My husband and I of 35 years are the same weight we were when we married. Both of us do not want to be fat and so don’t eat crap, don’t eat huge amounts and keep fit. It’s not difficult. Once you start getting fat your hormones change and the body loses control of how to respond to food and satiety.
    The modern environment makes it very diffficult in USA( and many other countires) to eat properly. It’s like alcoholics and people wanting to stop smoking- very difficult if everyone else is eating, drinking , smoking.
    People make money from feeding us huge amounts of cheap, easy eating, nice tasting food. Kids have no chance when they are given crap food from birth. They know nothing else and become addicted to sweet and fat food.
    What I don’t understand is how can people put up with being ugly and uncomfortable. When all the fat related illnesses catch up with them they still can’t change their behaviour.
    The scientists churn out a myriad of scientific papers explaining the how and why and physiology of fatness but in the end as Slightly Concerned has said- you are what you eat

  • maddie

    girls have bigger hips and legs because they have the babies. You can have broad hips but still not be overfat. look at Jo Lo- keep fit and and strong and even if you have braoder hips you are still healthy and look good.

  • http://hotmail mandy

    i am only 12 but has been thin since i was 8 i eat normal my weight is 32kg
    but iam thinner than a girl who weighs just 25 everyone just keeps teasing me

  • Another Skinny Guy

    Check out comment 69. I found that extremely helpful.

    I’m getting a little bit tired of the “Poor fat people” attitude in society. It’s simple physics: You use more energy than you take in. You lose weight! Eat less or use more energy.

    When are they gonna help the people desperetly trying to gain weight, cause fat is helpful. You’re better insulated, skinny people always freeze. You don’t get weak if you haven’t eaten for a little while and you don’t look like a friggin Holocaust survivor.

    I’d like to see a somebody give tips to the skinny people, cause we need it. If anyone know where to find information to gain weight, please share.

    If any fat people are going to complain about this. Don’t. Do something about it or accept yourself, I’d rather be fat, so don’t whine. You lucky bastard! It’s possible to cut down on the energy intake, but it’s much harder to increase the amount of energy your body chooses to digest.

    • Jonny

      @Another Skinny Guy – in response to your comment: “I’d like to see a somebody give tips to the skinny people, cause we need it. If anyone know where to find information to gain weight, please share.”…this is the answer: http://fourhourbody.com/Enjoy 😉

  • Guest

     I read some of your comments and my head almost exploded. People are the way they are because of their genetic makeup. That makeup decided everything about you. Hair color, eye color, weight, and what diseases you are susceptible too. Some of you think everyone can be skinny. This is absolutely not true. If you think this way then then you think that diet can change your color of hair or eyes. This is exactly the same for those who are light skinned and can not tan. They simply do not have the chemicals required in their skin to tan. They will only burn and get skin cancer. If you want to spend the money it cost $25,000 to have your DNA mapped and they will tell you exactly what you will die of and approximately when. Learn to accept people for who they are not what they look like. The smartest man in the world is Stephen Hawking. If you don’t know who he is, look him up. The man can not walk or communicate without the help of a computer because of a disease that he has. Thin don’t make you smart. It’s what you contribute to society that counts. Not what you own or what you look like because everyone looks like crap at 80 and you can’t take it with you when you die.

    • Rick

      I believe if you can mutate your genes to make something better about yourself, then go for it. I would like a bigger manhood and when scientists figure out how to mutate this gene, I’m going for it. If somebody would rather be able to tan then be pale, then go for it, change that gene. Mutating genes is the thing of the future.

  • Aaron Horner

    Sorry this is all bullshit, it has nothing to do with genes. I don’t get fat because my body uses fat as fuel, as opposed to sugars, as I am an athlete. I am on a paleolithic diet, consiting of just water, non-processed meats and berries.

  • Jason_hallisey

    I have always been underweight or a “Ideal Weight”. I have been physically active, workout, and eat a healthy calorie intake. However, after a I stopped taking Prozac and benzo witch I had taken for two years, I went from 105 to 120. While that is still a healthy weight its upsetting because I feel like maybe  those drugs screwed up my metabolism. I don’t know, I was trying to see if anyone knew any information on this, and worn other people who come off these drugs suddenly.

  • C.

    Wow — this sounds exactly like me! I’m seventeen years old, female, and for the past — oh, I don’t know… five years? — my weight has fluctuated anywhere between 118 and 127 lbs (rough guesses). 

    For eight years — until high school — I played soccer, so that probably helped, and then for five years — until this past June — I took taekwondo, so it’s not that I haven’t been active. But recently, I was diagnose with a form of asthma, and I am allergic to the inhaler. Thus, I rarely find an opportunity to seriously exercise for more than perhaps five minutes, because I will have an attack. 

    My older sister also took taekwondo for a few years, and exercised just as much, if not more than I did, but she still had trouble losing weight (she’s recently made progress, and I’m proud of her). 

    I have noticed, though, that I am practically incapable of eating when I am full, and will walk randomly around the house when I am bored. So maybe I fit the bill for what these scientists are saying, and maybe I don’t. I think it’s partially genetics, and partially lifestyle. I’m very thankful to have the ability to maintain a healthy weight, as I know that some people have medical conditions that make it practically impossible. 

    For the record, I eat fast food, I drink soda — one to three times a week — I eat until I’m full — but not after — and I have dessert. 

    But for people who see themselves in me, beware; my mom and the aforementioned older sister were this way until they were about twenty, and then they became ‘normal’ people, so it is possible that this wonderfully fast metabolism is not permanent. 

    Enjoy it while it lasts!

  • Janbay

    “The smartest man in the world is Stephen Hawking.”


  • Kjuarez9

    but im scared i weight 80 and im 14 going on 15 and i eat more than 10,000 calories a day!! Is that normal?? >.<

  • http://www.yourgreatabs.com Leslie Jane

    Those people who have very fast metabolism will eventually gain weight as they age. Body metabolism activity decreases as age increases. That’s a solid fact. 

  • Lil_dimond

    i wish i could it lots and lots of food and not gain weight

  • somanyquestions

    So a person whose fat is not converted to energy (thereby making the fat go to the every increasing waistline) do they posses less energy (less stamina) and hence ultimately aren’t able to work as much as the others who don’t put on weight?

  • Pingback: Why Freezing Fat could be the right choice for many()

  • Jumbo

    Its because fat people don’t stop eating. It really is that simple.

  • Anitzelescobar

    thats cool im 10 and i never want to get fat so make the magic pill plz

  • Jesseclark152

    Well that’s just great. The rest of us can’t even see our feet after a single apple. Genetics.

  • Josephhollins

    I want to get fat and I think I don’t have the MGAT2 thing cuz my body literally tells me in my sleep “i REFUSE to get fat” so i need help on that. what should I doto get that fat I want???

  • BecauseImShapedNasty

    Im skinny, but if i eat allot, I gain weight.

    Which makes me mad, because i work out twice a day and eat healthy.
    But i still gain weight even if i do this.

  • Cwarrin

    There is no such thing as a “fat gene” or a “skinny gene.”  The basic difference between fat people and skinny people is that skinny people eat less calories than fat people on a monthly basis.  It has nothing to do with your genes or even what type of food you eat.  It is just as simple as “calories in” vs. “calories out.”  Some skinny people exercise a lot, so they burn more calories, some skinny people don’t exercise but they also don’t eat excessive amounts of calories on a day to day basis which allows them to gain weight.  I have lived with skinny people and fat people, and that is all it is.  

    • Rick

      I do not believe this for one second. I know skinny people that drink sodas and beer everyday and are skinny as ever, and people with the same intake that are fat. If you were to conduct an experiment on sugar and diet intake compared to skinny and fat people, you will find that weight has nothing to do with what you do or do not consume, but rather the persons genes. I mean come on, how many big orientals are there? They all have the skinny gene. Enough said.

      • K

        Called sumo wrestlers…

    • knat

      you have no clue what your talking about, I have a friend that never works out, popped out 3 kids, and eats whatever she wants whenever, and is the same weight from high-school…obviously something is going on there…

  • Bob

    lucky me my family docent have the fat gene we eat so much and not one of us is the least bit fat

  • Katlin

    I eat a lot and only weigh 124 pounds 

  • AskingLaura

    i really wish i could gain some weight…i hope i’m not missing that fat enzyme…i looked into the mirror and saw myself way to skinny :/ and i did not like it at all. people say i look ok. but i really don’t think so. i think i look to skinny…

  • Lalala

    i want curves and want to gain weight, but no matter how much i eat, it doesnt do anything!! 

  • Miguellozoya56

    i been loosing weight since i been having sex 3 to 5 times a day

  • Samuel

    is this topic about mice or why skinny people cant get fats

  • Jaker123

    im one of them. im very skinny and i eat so much but i dont get fat

  • Shabena Nazar

    any body pls help i have 30yrs but still 35kg.How can i gain my weight

  • Randomguy45

    That explains why I’ve always been skinny no matter how much I eat… Guess the fat my body does not absorb is instantly flushed down the toilet.

  • Kuttuvadakkan

    am very slim how gain my wight 

  • Delcreeps

    Omo~ T.T I wish I born without the fat enzyme. So, i can eat 23,000 Big Macs 😀 And 12 packs of fries :p

  • R44d

    i eat mostly everything, like everyting 1 to 4 snacks a day. Im very strong slim build, im very active in a lot of sports. i am training mostly every day. i have six pack i have huge musculatures all over my body, but still i am slim i weight 69kg, 21years 1.78M. I am proud of myself for looking that good. Yes there is only one chance to live the life you always wanted 2. i said only 1 life..more training and sport!

  • Nunya Biznez

    This is my husband. Curse him… I’m glad I nabbed those genes for my offspring, though.  I hope they all have that gene and can’t get fat like he can’t get fat.

  • Rick

    You have the right to change anything about yourself that you do not like. Nobody can tell you what you can or can not do with your body (Not even God has that right). What you desire to change about yourself is your privilege. Mutating genes is very complicated. In most cases, you can add or change cells but you cannot deplete them without surgery or abstraction. (Another words, if you have a very big nose you don’t like, gene mutation cannot change it. You will need physical abstraction). Addition and subtraction are two completely different concepts when it comes to DNA blueprint. In a lot of cases we are talking death or disease and that is why it is so hard for scientists to advance with DNA mutation. We are talking A LOT of liability. It’s like taking a Government scientist trying to play God and most of the time it just doesn’t work, but time is on our side. So when the time comes, life will be much more fair for us all.

  • http://twitter.com/IrishCuteness_ 1DMofo_

    I think I was born without that because I eat a lot but never get fat I stay the same size

  • pema tshering

    me too, i use to take good amount of food n use to do regular cycling but i am so sad that m underweight, i always wish i am like others with bodily fit gentle man. please help me

  • Ruby

    I so wanted to gain weight as I’ve been underweight all m life. To apply these “high calories more weight” logic, I have prepared a food chart for 3000 Calories per day, and I have followed it religiously for 4 months.
    and I ended up gaining 1 lb only…!!!
    Let me also mention I was not doing any extra exercise then routine domestic work at home
    Anyone wants to comment on these….?????

  • 2face

    The body doesn’t respond to genes. It responds to hormones. The MGAT2 gene must be determing somehow which hormones the body produces. The “magic pill” for weight gain or weight loss has already been invented many times over. It’s called, you guessed it, hormones. Unfortunately we cannot benefit from this knowledge since hormones are illegal. So forget about the “magic pill”. Whenever someone invents medicin that can regulate the weight, athletes will use it and subsequently it will be labeled as doping and politicians will make it criminal to sell or use.


Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!


Quirky, funny, and surprising science news from the edge of the known universe.

See More

Collapse bottom bar