I like how it's being positioned as "damage". It's the body working more efficiently with less fuel. That's not damage, it's adaptation and homeostasis.
The biggest losers: Metabolic damage or constrained energy?
81–90 of 284 posts
Re: The biggest losers: Metabolic damage or constrained energy?
#82A shift in understanding the metabolism has been gradually occurring since the 1990s with the isolation of leptin. What is leptin? Discovered in 1994, leptin is a hormone that signals the availability of energy reserves in the body. "High leptin levels are interpreted by the brain that energy reserves are high, whereas low leptin levels indicate that energy reserves are low", the latter causing the body to enter a re…
> However, low leptin levels causes the body to enter starvation mode, and hardcore dieting causes leptin levels to drop further. What about fasting? Dr Jason Fung wrote a book about fasting that IIRC says that it does not cause starvation mode.
Just looked up his book "The Obesity Code"; not sure if that's the one you're thinking of.
Dr. Fung says obesity is a basically a hormonal issue, not a caloric issue. He discusses a "causality test": "If we inject this hormone into people, they must gain weight". According to Dr. Fung, leptin and ghrelin don't pass this test, but insulin and cortisol do. Still, leptin and insulin appear to have a close relationship. "Insulin promotes fat storage. Leptin reduces fat storage. High levels of insulin should naturally act as an antagonist to leptin. However, the precise mechanisms by which insulin inhibits leptin are yet unknown." He also says that "too much insulin causes obesity" and that "obesity is a state of leptin resistance." (Sorry for that mini book review; I needed to understand what he was saying.)
On the fasting point, he's explicitly supportive not of regular fasting but intermittent fasting: "Diets must be intermittent, not steady...we cannot fast all the time. It won't work."
Based on my fast read of his work and my own understanding, intermittent fasting keeps leptin levels high enough that the body doesn't kick into calorie restricting mode. One approach which seems to accomplish this is eating close-to-zero carbs five days/week (say, during the week) and then eating lots of carbs two days/week (say, on the weekend). The burst of carbs will cause leptin levels to spike since the body now has tons of available energy. Over the week, the leptin levels will remain elevated, but since you're minimizing carbs, the body will draw energy from adipose tissue.
Re: The biggest losers: Metabolic damage or constrained energy?
#83A shift in understanding the metabolism has been gradually occurring since the 1990s with the isolation of leptin. What is leptin? Discovered in 1994, leptin is a hormone that signals the availability of energy reserves in the body. "High leptin levels are interpreted by the brain that energy reserves are high, whereas low leptin levels indicate that energy reserves are low", the latter causing the body to enter a re…
> This approach is generally referred to the calorie-in/calorie-out (CICO) model. While true to an extent, this perspective is too simplistic, given one key fact: leptin is primarily produced in adipose tissue [1]. This fact means body fat is actually an endocrine system organ.
This part I think needs more explanation. The reason calories-in/calories-out model is too simplistic (I would call it almost useless if not completely wrong) is because of mitochondrial uncoupling proteins [1] that control how much energy in the protein gradient gets converted to ATP and how much is lost to waste heat. These uncoupling proteins are upregulated by leptin so when your leptin levels fall, your body literally changes how efficient its metabolism is to do more work with fewer calories. Body fat isn't just an endocrine organ, it might be the primary metabolic controller with a nasty catch 22 feedback loop - which would help explain why a certain minimum percentage of body fat is required or else a person enter organ failure.
That's why there are some people who don't seem to gain much weight despite eating a lot of food: their bodies are naturally less efficient and lose a lot more energy to thermogenesis. Without taking that metabolic adaptation into account, CICO is nothing but harmful dogma that needs to die. Otherwise people are fighting what might be one of the most important biological adaptations humans have.
Re: The biggest losers: Metabolic damage or constrained energy?
#84Earlier quoted context omitted.
> However, low leptin levels causes the body to enter starvation mode, and hardcore dieting causes leptin levels to drop further. What about fasting? Dr Jason Fung wrote a book about fasting that IIRC says that it does not cause starvation mode.
Agree, straying from thermodynamics is wrong. Human fat holds around 8000Kcal per Kg. Stop eating altogether. Every the 8000th Kcal more or less you would have lost 1Kg of fat.
My reply to him addresses this. Intermittent fasting works better than starvation.
Re: The biggest losers: Metabolic damage or constrained energy?
#85Earlier quoted context omitted.
> However, low leptin levels causes the body to enter starvation mode, and hardcore dieting causes leptin levels to drop further. What about fasting? Dr Jason Fung wrote a book about fasting that IIRC says that it does not cause starvation mode.
Agree, straying from thermodynamics is wrong. Human fat holds around 8000Kcal per Kg. Stop eating altogether. Every the 8000th Kcal more or less you would have lost 1Kg of fat.
There’s the issue of not being able to decide what gets burnt. I’ve read that under certain circumstances, the body can actually burn the muscles faster than it burns the fat. Which obviously makes exercise harder.
Re: The biggest losers: Metabolic damage or constrained energy?
#86Earlier quoted context omitted.
I don’t understand how this needs anything beyond surface level complexity… you have fat people who for show reasons were tightly controlled on exercise and food intake - which works for well understood reasons - then they took that away and left the people to their lifelong established habits. Of course they regain the weight. These people didn’t magically create mass from nothing. They ate too much for their activi…
Welcome to weight loss discussion on HN, where any rational point like "eat less" or "calories in, calories out" gets downvoted and discussed to death. Apparently for this crowd taking medicines is better than stopping stuffing yourself, because you know, if you take a medicine you can keep stuffing yourself. Oh, and also "it's more complicated than that" is always a nice escape from the harsh reality of thermodynami…
It gets downvoted because it's stupid and unhelpful.
If your body has the wrong idea of how much fat it should store, it'll do its best to force you to eat more to get that fat, even if it makes you unhealthily overweight. Medication can fix the body's idea of how much fat it should have.
Taking that medication doesn't mean you can keep stuffing yourself, it means you can finally _stop_ stuffing yourself, without your body incorrectly reporting that it's starving. The point of the medication is to make it possible to do the right thing.
Re: The biggest losers: Metabolic damage or constrained energy?
#87Earlier quoted context omitted.
Sure, blame the people. Fat shame all you want. Problem solved. Done. It's so easy, just stop eating so much. As if fat people haven't heard that one a bilion times over. As if fat people havent tried time and time again. Personal responsibility! you put that stuff in your mouth, rah! rah! Personally I'm actually sick of people having no eye for the bigger picture, for many systemic reasons and larger society, and ju…
Well, it is easy to hold people accountable for what they themselves put in their mouths no? That being said, there is some issues with the prevelance of hyperprocessed unhealthy foods. The fact that the most unhealthy options also tend to be the cheapest and easies, really do not help.
Easy, yes, but not exactly correct and certainly not helpful in the slightest.
Re: The biggest losers: Metabolic damage or constrained energy?
#88A shift in understanding the metabolism has been gradually occurring since the 1990s with the isolation of leptin. What is leptin? Discovered in 1994, leptin is a hormone that signals the availability of energy reserves in the body. "High leptin levels are interpreted by the brain that energy reserves are high, whereas low leptin levels indicate that energy reserves are low", the latter causing the body to enter a re…
> This approach is generally referred to the calorie-in/calorie-out (CICO) model. While true to an extent, this perspective is too simplistic, given one key fact: leptin is primarily produced in adipose tissue [1]. This fact means body fat is actually an endocrine system organ. This part I think needs more explanation. The reason calories-in/calories-out model is too simplistic (I would call it almost useless if not…
CICO doesn’t work across individuals for reason you outline (just because I lose weight with a certain level of calories, doesn’t mean you will, etc.)
But for a single individual, working to establish your base metabolic rate by counting every calorie and weighing yourself regularly, you can always find a way to be successful with the CICO model. If you establish a baseline that your metabolic rate is (say) 2000 calories a day, then eating 1600 calories a day will cause you to lose roughly a half-pound to a pound per week. It does not mean that every individual’s baseline metabolic rate is the same.
As you also outline, your base metabolic rate also changes as your weight does, so re-baselining by continually measuring caloric intake and your weight to recalibrate is always going to be necessary.
Given the above CICO almost seems tautological: Measure the weight loss you actually observe at a given calorie level, and that tells you… how much weight you will lose at that given calorie level. So it is almost useless as you describe.
BUT, the main reason I’m still a proponent of CICO is that it simplifies dieting away from thinking about what you eat, and instead focuses on how much you eat. If I establish that I need to eat 1800 calories a day, I can still have a Big Mac meal and drink some beers. But I may not be able to eat much else that day. That alone makes it useful for me. What isn’t useful to me, are diets that essentially limit the type of food you eat and tell you to just go nuts and eat however much you want: I will often find myself hating the foods I’m restricted to, and the quantity I eat may end up being such that I gain weight anyway.
To me, CICO is simply a technique that says “actually measure how much you’re eating”, no more and no less. That is what makes it a useful tool.
Re: The biggest losers: Metabolic damage or constrained energy?
#89Thoughts on Adenoviruses as being a root cause of obesity? https://www.geneticlifehacks.com/weight-loss-genetics-obesit... "Interestingly, animal studies show that the gain in fat mass is not due to eating more or moving less… Animals ate the same amount of chow, but those infected with adenovirus 36 increased fat tissue by 60-80%." https://pubmed.ncbi.nlm.nih.gov/17135605/ "A 2004 twin study showed that the Ad-36 an…
It may be a contributing factor in some cases. The study published in Obesity you link says the adenovirus affects insulin, leptin, and corticosterone. An important note about the third item: "In many species, including amphibians, reptiles, rodents and birds, corticosterone is a main glucocorticoid, involved in regulation of energy, immune reactions, and stress responses. However, in humans, cortisol is the primary glucocorticoid..." [1]. Note that the adenovirus itself wasn't definitively causing obesity, but obesity is caused by the adenovirus' effects on certain hormones.
I highlight this because obesity is increasingly being reestablished as a hormonal problem. See my post and replies for more information about this change: https://news.ycombinator.com/item?id=38942521
Re: The biggest losers: Metabolic damage or constrained energy?
#90Earlier quoted context omitted.
> This approach is generally referred to the calorie-in/calorie-out (CICO) model. While true to an extent, this perspective is too simplistic, given one key fact: leptin is primarily produced in adipose tissue [1]. This fact means body fat is actually an endocrine system organ. This part I think needs more explanation. The reason calories-in/calories-out model is too simplistic (I would call it almost useless if not…
CICO doesn’t work across individuals for reason you outline (just because I lose weight with a certain level of calories, doesn’t mean you will, etc.) But for a single individual, working to establish your base metabolic rate by counting every calorie and weighing yourself regularly, you can always find a way to be successful with the CICO model. If you establish a baseline that your metabolic rate is (say) 2000 calo…
Knowledge of leptin changes this because what you eat does actually matter. The goal should be intermittent fasting, where you eat little-to-no carbs about five consecutive days/week and then plenty of carbs two consecutive days/week. This approach ensures leptin levels in the obese body remain high enough to prevent onset of starvation mode while minimizing glucose levels to promote catabolic action on body fat [1].
The bottom line is: you're welcome to eat your Big Mac and beers, just only two days out of the week.
Also, stress has an important role to play on weight loss. Stress causes your adrenal glands to release cortisol. Cortisol increases glucose levels through gluconeogenesis by making glucose from non-carbohydrate sources, such as proteins from muscles.