Misunderstanding Metabolism

[Rianne]

Great article about the body's metabolism, weight loss, myths about expending energy. After reading this, I realize I am wrong about a few things how the body works.


https://getpocket.com/explore/item/...-metabolism-here-are-9-facts-to-clear-that-up

 

[haha]

Great article about the body's metabolism, weight loss, myths about expending energy. After reading this, I realize I am wrong about a few things how the body works.


https://getpocket.com/explore/item/...-metabolism-here-are-9-facts-to-clear-that-up

Excellent article Rianne. Thanks for posting.

Ha

 

[mamadogmamacat]

Interesting.

one caution is its basically a blog post (copied from Vox), so would have to do more research to check provenance.

Anecdotally, I've managed to lose, so far, 35 lbs, and keep it off for a couple yrs so far, on a low carb and high fat diet. The high fat part is in conflict with one item mentioned in this article. Article makes no mention of the low carb part. And. I'm not at all hungry most of the time, again in conflict with this article.

 

[haha]

I really wonder about this thesis that not much can be done about excess weight, either with exercise or diet.

I really have no idea, but I lived with 5 other guys through college, and I am still close to them. One used to get fat over Christmas Holiday, maybe 25 pounds. He always took it off in January, with moderate dieting and daily swimming.

50 years later, he is still lean. The other 4 look about the same (lean) as they did at 20(regarding weight, not wrinkles!) I weigh 5 or 6 pounds less than at 20. I see normal looking men and women every day, many more of them than fat looking people.

My mother and father were both lean until they died. One brother and I were always lean and always exercising. My other brother and only sister exercised little, and are both fat now.

Also, how about the idea that surgical weight loss is permanent or at least may be, but weight loss from dieting and exercise rarely lasts? Sounds like only if you give money to doctors can you lose weight and keep it lost. Suspicious.

Ha

 

[Rianne]

The article says to me, there is much more going on in the body than carbs, fat, exercise and calories. Metabolism controls much more than I thought. Everyone is different, no one size fits all. Forced weight loss is futile. What's the point? The body reverts back to where ones metabolism is naturally.

When I see an obese person I judge by thinking fat and lazy. There is so much more going on. I discovered I am comfortable eating early, usually before 4 pm, because I sleep better, feel rested and energetic. I am at my desired weight and have been for many years. If I eat high carb (pasta) and a large portion at 6:30, I am miserable all night and usually the next day. Same with fried foods, large amount of protein and fat (saturated fat). I simply cannot do it. My body screams no. I eat nuts, seeds, avocado, some bread but mix fiber with those foods.

 

[Rianne]

Interesting.

one caution is its basically a blog post (copied from Vox), so would have to do more research to check provenance.

Calling this article a blog post makes no sense. Various highly respected medical professionals and studies are quoted.

IMHO, the big waste of time is following ridiculous fad diets, so many I cannot bother to repeat. The only thing that makes sense is low sugar. We are not hummingbirds. Carbs, fat, fiber, protein all play an important role in healthy weight maintenance.

 

[Sunset]

Interesting.

one caution is its basically a blog post (copied from Vox), so would have to do more research to check provenance.

Anecdotally, I've managed to lose, so far, 35 lbs, and keep it off for a couple yrs so far, on a low carb and high fat diet. The high fat part is in conflict with one item mentioned in this article. Article makes no mention of the low carb part. And. I'm not at all hungry most of the time, again in conflict with this article.

I have a relative who has been doing the low carb, high fat protein diet for a year. She lost 50 lbs, and loves the diet. There is no feeling of deprivation as she eats good tasting filling things.

 

[Sunset]

Last year, in the summer I was doing lots of physical work, nothing extreme, but I'd spend a couple of hours per day digging holes, mixing by hand cement, cutting down trees, etc.

I didn't diet at all, there was no intention to lose weight, in fact I ate whatever I wanted including "treats". I certainly built some muscle and I lost over 10 lbs and my gut.

Since then, I've sat at my computer, gone on a vacation & cruise, and I have my tummy back and feel sluggish

I've realized I eat pretty much the same all the time, so it's a matter of how many calories I burn off that determines if I gain/lose or stay constant.

 

[Which Roger]

The article seems really pessimistic about exercise. In (2) they talk about how physical activity accounts for only a small part of the total calories we burn, because the average person doesn't have much physical activity. Isn't that the whole point of exercise, to burn more calories than average? In (5) they acknowledge that building more muscle mass increases basal metabolism, but then say this will only lead to weight loss if you don't eat more (but not that you can eat more and not gain weight). And most people won't keep up the activity to maintain the extra mass. But what if I'm not most people?


A lot of the other stuff (some people have higher/lower basal metabolism than others, metabolism decreases as we age, starving ourselves by dieting decreases metabolism, most people who lose weight gain it back because they don't stick to what they've been doing) is pretty well known.

 

[bjorn2bwild]

The article seems really pessimistic about exercise. In (2) they talk about how physical activity accounts for only a small part of the total calories we burn, because the average person doesn't have much physical activity. Isn't that the whole point of exercise, to burn more calories than average? In (5) they acknowledge that building more muscle mass increases basal metabolism, but then say this will only lead to weight loss if you don't eat more (but not that you can eat more and not gain weight). And most people won't keep up the activity to maintain the extra mass. But what if I'm not most people?


A lot of the other stuff (some people have higher/lower basal metabolism than others, metabolism decreases as we age, starving ourselves by dieting decreases metabolism, most people who lose weight gain it back because they don't stick to what they've been doing) is pretty well known.

Yeah, the biochemistry/physiology of metabolism is so complex, simplifying to a handful of facts can be misleading.
A long but most interesting article on metabolic flexibility from Oxford Endocrine Reviews ------

Essential Points

• Metabolic flexibility describes efficient switches in metabolism depending on environmental demand
• Mitochondria play a crucial role in determining metabolic flexibility
• Metabolic inflexibility is a hallmark of many age-related metabolic diseases but also plays a central role in, for instance, cancer and immune metabolism
• Molecular and signaling pathways drive metabolic flexibility and often serve as metabolic sensors
• Metabolic flexibility pathways are therapeutic targets for age-related diseases, similar to caloric restriction or exercise

(8) in 1999 when they studied fuel selection in skeletal muscle in lean and obese individuals after an overnight fast. Specifically, they discovered that skeletal muscle of lean individuals showed a remarkable ability to adapt fuel preference to fasting and insulin infusions and were therefore designated as metabolically flexible (8). Insulin-resistant obese patients however manifested a lesser reliance on fatty acid oxidation compared with lean individuals and did not show increased fatty acid oxidation after fasting or reduced fatty acid oxidation after insulin infusion. Because of their inadequate responses to metabolic challenges, these patients were named “metabolically inflexible” (9). More recent work showed that, upon consumption of a high-fat diet, lean subjects with adequate metabolic flexibility were able to increase fatty acid oxidation (FAO) at the expense of glucose, whereas obese individuals were not (10). Lean individuals also showed an increased expression of genes involved in fatty acid transport and oxidation compared with little or no change in their obese counterparts (10).

A good example of cell intrinsic metabolic programming upon physiological stimulation occurs in skeletal muscle. Skeletal muscle consists of oxidative (type I) and glycolytic (type II) fibers, which differ in their metabolic abilities. Oxidative muscle fibers have a high mitochondrial density; hence, they prefer oxidative phosphorylation for ATP production. They also contain more lipid droplets and rely on FAO. Glycolytic muscle fibers have a low mitochondrial density and rely predominantly on the breakdown of stored glycogen by glycolysis for their ATP production........
As such, regular physical exercise is a classic example of how metabolic flexibility is regulated by transcription factors. During acute exercise, an increased AMP/ATP ratio, sensed by AMPK, increases transcription, translation, and activity of the transcriptional coactivator PPAR gamma coactivator 1-alpha (PGC1α..........

The increase of mitochondrial biogenesis and FAO improves insulin sensitivity. The role of PGC1α in metabolic flexibility is underlined by observations that basal PGC1α skeletal muscle expression is reduced in sedentary subjects (49)

https://academic.oup.com/edrv/article/39/4/489/4982126#

 

[Katsmeow]

I have done a lot of research and reading on metabolism. I wrote a weight loss blog for several years while I was losing about 65 pounds and maintaining the loss.

The article strikes me as a good basic article. I particularly was impressed by the fact the article makes it clear how there is a lot of uncertainty about some areas. I have read a lot of the underlying research on metabolic adaptation and why it can continue for years. I have read the Biggest Loser studies and they are quite interesting.

The one weakness I felt the article had was in the area of body composition and metabolism. It does mention that if you have more muscle you burn more calories. However, it says this is marginal. I would disagree with this. The Katch McArdle calculator gives a ballpark of your metabolic rate depending on body fat.

Take a woman who is 65, 5'4" tall and 145 pounds. If she is 45% body fat, her basal metabolic rate (what she burns just by being alive, with no activity) is 1151 calories a day. That same woman, if she has 25% body fat would burn 1435 calories a day. That is almost 300 calories a day more and once you figure in activity it is over 300 calories a day more. That is a lot. That can make a difference in maintaining your weight versus slowly gaining. This is way, way more than marginal.

Also the article says it is impractical to maintain the workouts required to keep the muscle mass. I don't really agree with that. If you could do the workouts to get to 25% body fat then it is far easier to maintain the workouts to stay there. Note -- I am talking about things that are not that difficult to maintain. A woman at 25% body fat is not extremely low in body fat. It would be way more challenging to maintain 15%.

 

[Midpack]

The one weakness I felt the article had was in the area of body composition and metabolism. It does mention that if you have more muscle you burn more calories. However, it says this is marginal. I would disagree with this. The Katch McArdle calculator gives a ballpark of your metabolic rate depending on body fat.

Take a woman who is 65, 5'4" tall and 145 pounds. If she is 45% body fat, her basal metabolic rate (what she burns just by being alive, with no activity) is 1151 calories a day. That same woman, if she has 25% body fat would burn 1435 calories a day. That is almost 300 calories a day more and once you figure in activity it is over 300 calories a day more. That is a lot. That can make a difference in maintaining your weight versus slowly gaining. This is way, way more than marginal.

Also the article says it is impractical to maintain the workouts required to keep the muscle mass. I don't really agree with that. If you could do the workouts to get to 25% body fat then it is far easier to maintain the workouts to stay there. Note -- I am talking about things that are not that difficult to maintain. A woman at 25% body fat is not extremely low in body fat. It would be way more challenging to maintain 15%.

+1. Regular exercise can significantly reduce weight IME.

I found it puzzling the article claimed you really can’t change your metabolism yet it goes on to say more muscle will change your metabolism, and that losing weight (by whatever means) will also alter metabolism.

The fallacy most people have is that you can diet and/or exercise until you reach some desired weight, and then return to your old habits without regaining the weight. Your old habits led to the overweight condition in the first place, and they will again. How many have heard a dieter say ‘I’m going to diet until I lose X pounds and then I can eat what I want again’ - that simply doesn’t make any sense. Unless you’re going to make permanent changes in your eating habits and/or exercise, you might as well not bother - that’s the “yo-yo” diet phenomenon. Your body will reach some sort of “equilibrium weight” based on your good or bad habits, and a new equilibrium if you revert to past behavior. And as the article says, your metabolism will gradually slow with age, another caveat.

 

[Katsmeow]

One distinction that I think is important that is touched on in the article but not really gotten into. It is true that for most people the contribution of formal exercise to weight loss is not great in terms of calories.

The argument is made that well if you burn an extra 300 calories in exercise and it makes you hungry and you eat 300 calories then the exercise didn't help weight loss. If you get hungry and eat 400 calories then it was counterproductive.

That is true -- to a point. However, even if you do burn 300 calories in exercise and then eat another 300 calories that can still help weight loss because it may make the dieting more sustainable. I am on the shorter side and don't burn a lot of calories in terms of BMR. If I don't get activity, I can maintain my weight on around 1350 calories a day. To lose weight I would have to cut that. That is challenging. On the other hand if I am more active I can burn more calories each day and cut that. Let's say I burn 500 calories in activity (some exercise, some non-exercise). And, lets assume I eat 300 of those calories. Well I am now able to have a calorie deficit while eating more calories. That is far more sustainable.

If I have don't exercise and I have to eat 1200 calories a day to lose weight -- that is hard. But if I do 300 calories of exercise and eat all 300 calories then I am eating 1500 calories a day and that is far more sustainable long term.

The other thing is that while exercise may have a relatively small effect for most people during weight loss, it is a huge factor in maintaining weight loss. People who exercise do far, far better in maintaining weight loss.

 

[daylatedollarshort]

We're trying to eat more of a Blue Zones, plant based kind of diet to live longer and ward off chronic diseases. The Blue Zone recommends 5% of calories from animal based foods and the MD Anderson web site had cooked meats at 18 ounces per week. I didn't think we were big meat eaters before but that is requiring a big change in meal planning for us. Even at the 18 ounces limit that is less than 2 ounces of meat a day.

Link - Can a vegetarian diet lower cancer risk?
https://www.mdanderson.org/publicat...etarian-diet-and-cancer-risk.h31Z1591413.html

 

[Rianne]

So many examples are specific to the individual. Calories in, calories out is a myth. Two TBS of mixed nuts and sunflower seeds = 200 calories. A donut = 200 calories. There's nothing wrong with a donut every so often. I eat mixed nuts and seeds everyday. It's portion control and enjoying treats occasionally.

Again, this is specific to the individual. I worked with a lady who had bariatric surgery. They tied off her stomach so she would feel sick if she ate too much. Basically, she got a smaller stomach from the surgery. After a year, her stomach stretched as she gradually ate more. She was back to her original weight over time.

For me, a non medically trained person, found my ideal weight and overall energetic lifestyle from eating early, portion control and avoiding processed (highly sugared, salted, fatty) foods. I know very slender people who do not exercise. There is no one size fits all.

I found the article interesting because it addressed metabolism as a key component in how our bodies utilize energy.

IMHO, exercise is beneficial for blood flow, muscle and bone health, mental health. I do not view exercise as a way to lose weight.

 

[Katsmeow]

So many examples are specific to the individual. Calories in, calories out is a myth. Two TBS of mixed nuts and sunflower seeds = 200 calories. A donut = 200 calories. There's nothing wrong with a donut every so often. I eat mixed nuts and seeds everyday. It's portion control and enjoying treats occasionally. .

Whether it is a myth or not depends on what you are talking about. Weight loss and health, though, are not the same thing. Type of calories matters a lot to health, but not so much to weight loss.

Certainly calories in and out it not a myth with regard to weight loss and weight gain. If you have a calorie deficit you will lose weight. The research is pretty clear on this. For those interested in weight loss, the amount of calories consumed makes a huge difference. If I eat 500 calories more per day than I burn -- even very healthy calories -- I will gain weight. If I have a 500 calorie deficit of unhealthy foods I will lose weight. So, calories in and out really does matter for weight loss.

However weight loss and health are not the same thing. I agree with you about nuts and seeds and donuts. I have a serving of nuts almost every day and have done this for many years. It is calorie dense but they are good healthy foods that taste great. So - in terms of weight loss, I focus mostly on calories. But, in planning my own eating I also look at nutritional quality.

 

[Rianne]

A calorie is a measure of energy. My takeaway is the way the calorie is processed and utilized in the body. Is is stored (fat)? Is it passed through (fiber)? Is it processed through the liver? kidney? Does it affect blood pressure? blood sugar? Is it retained or does it serve a purpose to feed and energize the body in a positive way? Is that calorie going to help me be healthy? or sick? That's what I mean by calories in calories out is a myth. The higher my metabolism, the more efficient use of calories. This article is a window into an extremely complex process that I don't profess to begin to understand.