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Adipose tissue retains an epigenetic memory of obesity after weight loss

nature.com

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Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#181

Earlier quoted context omitted.

Jason Fung is probably the world's leading research expert on obesity. If you want videos to watch on it, it starts and ends with this guy. He has done a ton of lectures and blogposts going back over a decade, and also has the stereotypical clickbaity YouTube videos. https://www.youtube.com/watch?v=YpllomiDMX0

He has surely dedicated a significant portion of his life to his own pet theories on obesity, but to consider him a well-regarded expert is very misleading. He has quite a few claims that are just...ridiculous, and his pop science books have some serious flaws (as reported by actual experts).

While I don't doubt you, it would be helpful if you cited these experts, so people can learn.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#182

Earlier quoted context omitted.

Similar adaptions occur in muscle. The extent of new muscle fiber development (hyperplasia) is debated, so there are multiples factors influencing how muscle retains some memory of past strength ability. Once you’ve reached a level of physical strength it’s easier to return to that level in the future. This has been a topic of debate in the sports world because past anabolic steroid use could therefore carry benefits…

I can't remember exactly what I was listening to, maybe some kind of NPR podcast. But the doctor was mentioning that none of the influencers influencing young people to try T and Steroids (which is rampant right now) are ever mentioning that you are on a ticking clock to infertility as soon as you start this stuff. Some people can regain their fertility but it might take years, and some people are going to be permane…

Testicular atrophy and HPT axis suppression is a thoroughly documented side effect of TRT and steroids. Even beginner bodybuilders know that taking steroids will crush their natural testosterone production. They can kind of bring it back by taking short courses and using certain medications after the cycle, but most discover that some permanent damage is being done with each cycle.

There are two problems with framing it as an infertility problem:

1 - It reduces fertility but many users retain some fertility. The bigger problem for most is that natural testosterone production won't come back to the same level if they ever discontinue, so they're on it for life. Managing testosterone injections every week or multiple times per week for the rest of your life is doable but a pain, especially if you have to travel or you're not the best at keeping up with prescriptions. There are also ups and downs and side effects that come from artificial testosterone dosing. Many people are surprised to discover that after the first year or two they don't feel "great" any more and it's just back to where they started, but with a lifetime dependency now. Others get serious side effects like Gynecomastia (breast growth in men, possibly requiring surgery) or secondary hormonal alterations that negatively impact mood, cognition, or libido.

2 - Many young men in their 20s or even teens see infertility as a positive rather than a negative. It's very common for people of this age to think they've made up their mind for life, but they have yet to even have a serious relationship or even know any peers with kids. People who work in fertility fields are starting to see a lot of men who went into TRT or steroids when they were young because they thought the consequences would never be a problem for them.

> Plenty of those "alpha male" guys on social media are shooting blanks.

Honestly, they don't care. I skim the testosterone subreddits occasionally and many people brag and joke about how small their testicles are.

It's crazy to me to see this shift happening. TRT clinics that advertise on the radio, TikTok, and everywhere else will entice people to come in for "free tests" but the trick is that it doesn't matter what your numbers come back as, they'll always find a way to prescribe you TRT because it's easy recurring revenue for them with lifelong dependence attached.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#183
post #2

As someone who's struggled with weight loss, and have known others to struggle with it well, I think we colloquially called this "slow metabolism". It always did feel like it was easier to gain weight than lose it, especially fat weight and not muscle weight for me. I was recently sent a video about fat adaptation (basically teaching your body to be better at burning fat) by a very fit friend, but I wonder how much o…

> It always did feel like it was easier to gain weight than lose it, especially fat weight and not muscle weight for me. It is the exact, polar opposite for me. I cannot gain even if I eat junk all day.

I had a friend who was trying to bulk up make that claim (he was 6', 140 lbs), and then when I finally convinced him to write down everything he ate in a day, it was like 1800 calories.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#184

Earlier quoted context omitted.

I can't remember exactly what I was listening to, maybe some kind of NPR podcast. But the doctor was mentioning that none of the influencers influencing young people to try T and Steroids (which is rampant right now) are ever mentioning that you are on a ticking clock to infertility as soon as you start this stuff. Some people can regain their fertility but it might take years, and some people are going to be permane…

This is interesting because about 20 or so years ago when I was super into bodybuilding, you couldn't talk about a "cycle" on a bodybuilding forum without talking about a "post cycle protocol." I know that's different than permanent TRT but I feel like you couldn't get very far researching that stuff without understanding that you natural test production (and sperm production) would get "shut down" as soon as you sta…

Yeah, it's well known that steroids shut you down. The problem with the broscience is that the PCT is talked about like it reverses everything like an antidote, but long-term bodybuilders often end up on TRT because eventually they can't get back to baseline.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#186

Calorie counting is the only truly reliable way to lose weight

The only true reliable way is to burn more than you eat. Counting calories is a way to keep track of that, but it's only going to be so-so accurate unless you only eat labeled food. I will certainly not measure the weight of a banana I eat, and anything else is just a very rough estimate as a banana can be twice the size of another banana. In general, when I was losing weight I did not really need to count calories,…

> I will certainly not measure the weight of a banana I eat, and anything else is just a very rough estimate as a banana can be twice the size of another banana.

This is the wrong way to look at it. Sometimes you'll have a larger banana, sometimes a smaller banana, but overall it'll average out. What you need is consistency to compare to your own previous measurements, not perfect accuracy.

For example: By counting my calories and keeping track of my weight, I've learned that I burn about 2200 calories per day. If I went over my foods and measured them perfectly it probably wouldn't be that number, but because I'm consistent in how I measure it I can know with certainty whether I'm above or below that limit. I've been able to reliably control my weight for a few years now because of this and I'm not even measuring, just eyeballing how much of things I use.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#187
post #2

As someone who's struggled with weight loss, and have known others to struggle with it well, I think we colloquially called this "slow metabolism". It always did feel like it was easier to gain weight than lose it, especially fat weight and not muscle weight for me. I was recently sent a video about fat adaptation (basically teaching your body to be better at burning fat) by a very fit friend, but I wonder how much o…

Fat adaptation is not bro science, it is what happens when you do not consume enough carbohydrates to meet your TDEE so your mitochondria “learn” to become really efficient at burning fatty acids. It’s the whole premise behind keto/low carb. When used to our modern high-carb diets, the adaptation takes some time for genes to activate, since we eat a lot and never have long enough fasting periods to be able to quickly switch between glucose and fatty acid metabolism.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#188

Well, yeah. Adipocytes multiply when you get fat. But when you lose weight, they don't apoptose, they just shrink in volume by giving up their lipid stores.

Similar adaptions occur in muscle. The extent of new muscle fiber development (hyperplasia) is debated, so there are multiples factors influencing how muscle retains some memory of past strength ability. Once you’ve reached a level of physical strength it’s easier to return to that level in the future. This has been a topic of debate in the sports world because past anabolic steroid use could therefore carry benefits…

> This has been a topic of debate in the sports world because past anabolic steroid use could therefore carry benefits into the future long after the athlete has stopped using the steroid.

Similar advantage is conveyed to athletes who had elevated (~male) testosterone levels in the past, even if they subsequently take blockers / go on HRT to ~female hormone levels.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#189

Earlier quoted context omitted.

Similar adaptions occur in muscle. The extent of new muscle fiber development (hyperplasia) is debated, so there are multiples factors influencing how muscle retains some memory of past strength ability. Once you’ve reached a level of physical strength it’s easier to return to that level in the future. This has been a topic of debate in the sports world because past anabolic steroid use could therefore carry benefits…

I can't remember exactly what I was listening to, maybe some kind of NPR podcast. But the doctor was mentioning that none of the influencers influencing young people to try T and Steroids (which is rampant right now) are ever mentioning that you are on a ticking clock to infertility as soon as you start this stuff. Some people can regain their fertility but it might take years, and some people are going to be permane…

The big, big problem is heart disease. Infertility might be bad for your family planning, but the high blood pressure will kill you.

Re: Adipose tissue retains an epigenetic memory of obesity after weight loss

#190
post #118

Doesn't similar happen for strength gain? People that have had larger muscles tend to have an easier time building them back up, as well.

> People that have had larger muscles tend to have an easier time building them back up, as well.

Yes, although I don't know whether that's epigenetic.

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