Why are thin people thin?

[Askye]

Makes sense thanks

[LeCheffre]

Copies of AMY-1 gene. Some folks have 1, some folks have 6. The more you have, the more amylase you make. The more amylase you make, the better you break down carbs, and the less hard it is on your liver.

There are other genes and factors that make control how many additional fat cells you make and what capacity your fat cells will allow themselves. If you make more, you can be one of those 600 lbs people. If you don’t make more, you can be one of those TOFI folks you hear about, who are thin with fatty liver and T2DM.

There’s also bacteria. Gut bacteria inherited and acquired from family and during your life.

There’s also Omega 6 consumption to consider.

And genetic predisposition to hormonal disregulation, like Hashimoto’s Thyroid, combined with environmental exposures that trigger the disregulation.

The TL:DR is that it’s complicated. Genes, environment, behavior, etc.

[emccally]

I am new here and new to keto, but to answer your question, I think it is a mix of genes and learned habits. You may have good genes, but have learned bad habits growing up, and therefore be ‘fat’. Or you may have just average genes but have learned healthy habits and naturally keep weight off. Most of my family is tall and thin. As kids, my siblings and I were so tiny (but tall) we could barely find clothes to fit. At 24, I am moderately active (as in I go to the gym maybe 3-4 times a week, but really do not push myself lol) and otherwise stay busy-ish around the house (stay home mom). I have good genes you could say-I eat what I want, when I want (even before keto) and have a BMI of 15 (quite ‘underweight’ you could say). However, I did learn healthy habits growing up as compared to many of my friends who struggle with weight. For one, it just isn’t a question as to whether I should work out or not… it just is something I was taught to do and have always done. Another I’ve noticed is that I have never been okay with the idea of ‘drinking my calories’. Growing up we could have water or milk (calories in milk obviously but stopped drinking it at a young age). So, I never found it ‘normal’ to drink soda, juice, or any other sugar-laden drinks, whereas my friends still constantly drink Mountain Dew etc. If anyone in my family grabs a soda, it’s diet. Again, that doesn’t mean it’s healthy (definitely not) but it is still a significant difference in calories. For us, dessert was a ‘treat’, meaning it didn’t happen every day, and when we did have dessert it was something special my mom made from scratch, as she refused to buy oreos, zebra cakes, etc and all the other goodies my friends got in their lunches, after dinner, etc. (and most of them are overweight now).

SO, sorry this is getting long, but there are lots of little habits that make a difference. Its easy to look at someone and see them “eating whatever they want” or to look at me on a day that I maybe downed a burger, fries and chocolate shake (before keto) and wonder how I don’t gain weight, but in my opinion it is the little habits that add up otherwise that make a difference in gaining weight or not. Growing up we never got to eat fast food, so as an adult I would maybe eat it once a month or less, and again, it was a ‘treat’ not a regular thing, whereas for many of my friends it is a regular habit.

I chose to do keto for energy reasons as opposed to weight loss, so I suppose you could say it doesn’t matter wether I eat carbs or not when it comes to weight, but I have never been one to ‘overeat’ as it just wasn’t something anyone in my family did. So…HABITS HABITS HABITS.

[Janie]

I could have written your post about my dietary habits growing up. Water or milk to drink, no fast food, no snacking, desserts were special occasion treats, etc.

I was not thin like my brother but not overweight at all - had a more athletic build. Never had a weight problem until my first child was born. I was 25. Bam. Same diet as before pregnancy. Weight from post-pregnancy not budge. Now I understand it was hormone-related. I could not understand why restricting my calories didn’t work anymore. I didn’t eat low carb, but I did not eat any sugar, no sugary drinks, etc. Very frustrating!

What I DID do was consume lots of fake foods with artificial sweeteners, snacked a lot, etc. I didn’t think it mattered as long as my total calories, points, etc was under my daily limit.

I wish I had discovered keto 30 years ago!!!

[Happyheart]

Or it could be that the foods you ate, most of the time, were not the kind that caused your body to raise insulin exponentially and you ate foods that were healthier than the premade sugar lade fare many others ate, keeping you from craving more of said foods.
I expect genetics have their role as well.
But i expect sugar, grains and low quality fats seem to have a big affect on our metabolism.

[Acn22]

Hey guys some awesome answers in here thanks for all the replies sorry i don’t do forums ever since Facebook came out lol

[Janie]

This isn’t Facebook in case you didn’t notice the difference. I don’t do Fakebook either but this forum has given me a wealth of information and support.

YMMV

[atomicspacebunny]

…and we have the classic ectomorph!

5 Reasons Ectomorphs Struggle To Build Muscle - Dr. Bubbs

[Brunneria]

Learning good eating habits makes absolutely no difference at all once something changes which causes insulin resistance.

This change could be one (or more) of many things. Changing sleeping patterns; insomnia, new baby, shift work. Changing eating; getting married, canteen at work, stress eating . Hormones; pcos, pregnancy, breast feeding, stress. Pain; chronic, acute, long term, short term. Emotional; grief, anger, frustration, boredom…

Every one of those things can affect us in ways that impact appetite, hormones and glucose regulation.

Every time I see someone say ‘well I had good eating habits until I started eating x y or z’. I want to bang my head against the wall.

That is too simple. And thinking like that doesn’t ever tackle/acknowledge the root cause. Plus it spreads blame and the ‘myth’ of ‘healthy eating’.

WHY did you START eating x y and z?
It will have been emotional, lifestyle, environmental, hormonal or trauma.

In my case I grew a prolactinoma (benign pituitary gland tumour that fucked up my hormones). Ain’t no amount of ‘healthy eating habit background’ that can compete with physical carb cravings and hormonal fluctuations like that.

Don’t sell yourselves short. And don’t perpetuate the ‘i was slim fit and cute til I got greedy’ myth. It’s bollocks. You were slim fit and cute until life hit you in the gonads and some tiny little straw broke the camel’s back and your metabolism couldn’t pretend everything was ok any more…

[anon54735292]

And don’t perpetuate the ‘i was slim fit and cute til I got greedy’ myth. It’s bollocks. You were slim fit and cute until life hit you in the gonads

but true.

[Westieholic]

I was definitely slim until…

Very active, muscular child (sprinter), ate what my diabetic grandma ate in the 70s, (low processed carb) until college. I never cared about food. Had to be forced to come in from running to eat. On the rare occasion I ate carbs, BINGEFEST, (like fresh-baked thanksgiving cinnamon rolls til I literally puked and could not lie down to sleep, or 33 snickers in a sitting) but it was VERY rare. Stayed slim.

My other, thin grandma was anorexic. Both parents (thin) were natural intermittent fasters. Dad literally skipped meals until whenever he developed a little pot belly. Other thin relatives ate mostly meat and veg, I observed, preventing the binge cycles. I had a “food is a celebration/a reward/love” mindset that others did not.

When EYE could choose my own food, (college) I was like a druggy. Cheetos, sugar cookies and dry tang powder, (!) instant tummy, but not yet “fat.”

I can see that I had a crazy insulin response, always, but when it was prevented by external forces, I was slim, scrawny even, with a flat tummy. A natural intermittent faster.

When I had food choice/access, I gained so fast… I felt the eating until it hurt, (and wondering why) weight gain that started in tummy and spread to lower body. I don’t. know. how. I never hit 600 pound life status, but was the fattest person in my family when I hit 250.

I heard on YouTube somewhere that sugar addiction is “addiction to your own endogenous endorphins.” Definitely true for me. Cardio takes away my binge urge. So does Keto.

[teri]

My mom has always been skinny, even though she was a type 1, now type 2 diabetic. She is a diabetic due to pancreatic problems caused by a recalled medication, though. Not diet or genes.

But she was skinny before and remained skinny even though she had to begin insulin shots and change her WOE. Which honestly is very similar to keto. She does a lot of sugar free stuff, but will have a treat occasionally. She doesn’t limit carb foods like rice, potatoes, or wheat bread, but she’s pretty healthy in terms of not eating “junk food” like cake and stuff. But she has always been around 135-140. I think that’s genetic for her. So that may have a lot to do with it. Idk. She’s now 60 years old and past menopause…

I take after her in our frames, we are both 5’7 and carry weight in the same way. But if I wanted to gain weight I could. If I ate pizza and junk food and didn’t work out I’d be about 160-170. At least that’s the most I’ve weighed. But I’ve been down to 110 by restricting due to an eating disorder. So skinny people aren’t always skinny by nature. A lot of times it’s on purpose - as in my case. I am in the 120s now recovering from another ED episode, and am currently trying to gain muscle weight with keto to get to the 130s. I could easily stop keto today and get in the 130s next month but it wouldn’t be a healthy 130.