T Nation

Is Body Fat Genetic?


Long time lurker, first time poster.

Was wondering if genetics play a role in BF%. We often hear about genetics being a key player in muscle development, but can certain people get leaner than others based on their genes?

Reason I'm asking is that I've always seemed to carry around a bit of extra body fat. Over the past year I've really done my best to blast it off (along with developing lean muscle) but I seem to have plateaued in BF loss, even though I have intensified my workouts. I'm at about 12% now and would love to get down to around 8%. Is that type of goal accomplishable for anyone regardless of age/genetics? Any thoughts?


Anything related to your body is effected by your genetics!

And no you have not limited by your genetics at 12% body fat. It may be tougher for you to get below that compared to some one else because of differences in genetic makeup but you can still do it.


Yes certain people are born with more fat cells then others. The hormone leptin is believed to play a role in this. ALSO during the very early years of a childs life they can develop more fat cells by eating a poor diet. THis helps explain the epidemic of fat kids you see who are somewhat doomed to be that way thanks to their fat stupid parents.

Are you completely screwed? NO! While genetic plays some role this in no way mean that diet, exercise and perhaps somewhere along the road, supplementation won't help you get lean. You're in the right place, and that's a legit question.

However the fact is it's not the answer. You determine the final answer and the tools to do so are here. Pm me if you have any questions, I'm always glad to help. Just a lil slow sometimes.


WideGuy or a doc out there, I'd be interested in your opinion on the following.

In some nutrition or biology class or some such, I was taught that adoloscence is the key time for an individual to change the quantity of fat cells in their body.

For example, if a child gains fat through their teenage years, they will actually increase the quantity of fat cells in their body. If this is correct, would it also be safe to say that the opposite also holds true?


The number of fat cells is genetic, but the number grows during childhood up to early puberty. And due to overeating, you can increase the number of fat cells by overeating. And you cannot decrease the number of fat cells, you have to decrease the size of them instead.


No. You are implying that starving a child would lead to them "losing" fat cells in number. Without liposuction, fat cells aren't disappearing. Yes, childhood and adolescent obesity can lead to the production of more fat cells in number than there would be had they not been overfat.

Other than that, barring extreme fluctations in weight, you are pretty much stuck with the same number of fat cells. They will simply either be "full" cells or "empty" ones. Empty fat cells take up little space.

As far as this topic, however, getting down to 8% body fat isn't impossible. There is the issue of further progress. Very few people could actually make further progress in terms of muscle mass while maintaining a body fat percentage that low. 12% isn't "fat" and actually makes me wonder just how out of shape you think you are.

There have been plenty of guys on these boards acxting as if they were on the verge of obesity when in reality, they were just short of "skeletalization".


Oh how I had known about how you can increase the number of fat cells in your body by eating shitty. I used to have a super fast metabolism, then as I grew and ate more, it disappeared cuz i ate lots of sugar and junk and now i cant get all that lean.


It isn't about just "eating shitty" (like most teenagers did and do). Unless you got FAT, obese, or "pudgy", the chances that you actually gained fat cells outside of puberty aren't that high.

Your metabolism is based largely on genetics and activity level. Many people get much less active as they get older and then blame any weight gain on their "slowed metabolism"...when it is actually them who slowed.


hit the nail on the head with that one.


I remember Dr. Ulrich Strunz writing in one of his books that you can, through excessive cardio, literally burn out a small number of fat cells, permanently. This is actually rather difficult for people who don't run marathons.

Fatcells of Fatasses are also better "trained" in holding a lot more fat. The amount of fat cells remains pretty much the same during your life.


Prof X,

I actually don't find myself to be out of shape....I realize that 12% body fat is reasonably low for a guy my age (early 30s), I am just looking to take it to the next level. Your average Joe would never mistake me for a skeleton but they wouldn't call me overweight either.
I guess I was just wondering if this plateau is something that I can overcome or if I am predestined to carry a bit more fat than I would like. I imagine my next step is to figure out a way to workout/eat smarter to help me acheive my goal. I've been working hard to acheive my fitness goals and now I am trying to get a bit more intelligent about it.