bruce19

Just thought this might be of interest.

https://getpocket.com/explore/item/m...=pocket-newtab

PJay120

I saw this article. I think it misses a major aspect that should be obvious: your body has some overall control mechanism, probably largely hormonal, that sets the basal metabolism, and also sets how it responds to changes in general activity level.

I can get out of shape for running or cycling, but after a few steady days, my capacity or fitness will jump back up. I have been a jogger since I was 10, so that is 45 years. I believe my body somehow knows when it is time to jump from some laziness mode to higher metabolism mode.

I believe our bodies work like this because, over time, humans have generally experienced periods of high activity - summer, or migration time, with periods of low activity - winter, non-migration time. Many Native American groups had regular periods of migration, and Bedouins did, etc.

This would be a "biological clock" that is geared to "seasons" that are not necessarily seasonal, in a timely sense. Your body wants to get in shape for migration, but not sustain that level of activity all of the time. Burning more energy leads to cell turnover. Too much cell replication eventually leads to cancer.

One line of thinking is our telomeres, that line up and separate the two dna strands at cell division, can only perform this function about 17 times in a cell lifespan. As we burn out our supply of some type of cell, this division process gets less precise, and cell replication activity gets less polices by DNA repair processes, and the replication process goes awry.

All that to set up the concept that our bodies can be boosted in metabolism, but that the body will want a period of rest, as well, to avoid this state of too much cell replication.

Some people believe that our body uses external input, such as sunlight, (as well as internal such as energy expended, breathing rate, etc.) to gauge the metabolic level. So, this would explain why we feel more sluggish in winter. Foods eaten in preparation for winter, and in winter, are different from those eaten in spring.

Spring is when the garden starts blooming. So, some people think that eating salad is telling the body it is in Spring mode. So, it prepares for summer activity and migration - by having metabolism get higher, and storing less fat. If you eat like winter is coming - carbs, fat - the body thinks it is fall winter, and puts on fat to survive the winter, and slows metabolism for this less active season.

Further, some people believe we do a range of things to mess up our metabolism set point. Like, having artificial light to extend the "day," or coffee to kick in one type of metabolism versus another, drive us to be in winter mode: lethargic and putting on fat.

The article say things like caffeine cannot change metabolism much. However, it is well documented that women who quit smoking will put on weight - typically 10 - 15 pounds. It seems like it is the metabolism, not the snacking. This phenomenon is actually one of the barriers to women quitting smoking, and addressing this should be part of smoking cessation counseling, and women should build this aspect into their quit-smoking plans - however they might want, such as accepting the eventual weight gain, or also changing diet and exercise.

So, I believe the article misses this "set point" aspect, like a home thermostat - and this can be changed by regular physical activity mimicking seasonal / migrational body needs.

This "set point" idea explains a few things. It is a more accurate and complex idea than "calories in- - calories out." Asa the article notes, if you "diet" to eat too few calories, your body perceives that you are in a famine, and the body is hesitant to give up fat.

Also, in my younger days, when I was very physically active for years, I could consume amazing levels of calories - beyond the noted 3500 - and stay slender.

Having kids at age of 40 slowed my recreational activity down. I have teetered between watching diet, or just not worrying about it, and have gained the pounds. I am at a weight I thought I would never be at. When I was 45 and finally felt my body fat move / jiggle as I jogged, I realized I now knew what most people know. Up til then, I had no fat on chest or belly to jiggle back and forth as I jogged. Now, I am just trying to be a good Dad, and grow old gracefully, and stay fit, and not get hurt!

Like the article says, we slow down with age!

Carbonfiberboy 

I've lost 17% of body weight over almost 30 years, down from 175 at 45 to 145 at 74. For sure my metabolic rate has slowed, but my leptin and ghrelin seem to be just fine. It takes very little food to end my hunger now, much less than it used to. As one's cycling power decreases with age, the only defense is to decrease kg.

I read the article a few days ago. Sounds about right. My comment on it is that metabolic rate varies a lot between individuals, maybe a factor of 2 if I recall the international study I saw correctly.

canklecat

The reference to "stay away from high-fat foods" makes me a bit skeptical about the entire article. That may be a single flaw in the article but significant since there's increasing evidence that dietary fat has little or no bearing on weight -- possibly not even on cholesterol, heart disease or stroke -- and that most obesity is due to sugar.

Seattle Forrest

Obesity isn't due to sugar any more than it's due to dietary fat. Full stop. Obesity is due to eating more calories than a person burns, over a long period of time. It doesn't matter what macronutrient those calories come from at all.

berner

I noticed some time ago when I was hiking and backpacking weekly summer, and winter. Winter pack loads are heavier due to carrying extra clothes and gear in addition to already wearing heavier clothes, insulated boots and wearing snowshoes. I noticed then that my friends would begin to warm up in minutes and begin unzipping or removing parkas where I was still warming up 20 minutes later. I've noticed the same thing on the bike. It takes about 20 minutes to feel 'warmed up'.

canklecat

You're misinterpreting what I wrote. Americans in particular consume far more sugar than they're aware of because it's added unnecessarily to so many processed foods. And over the past century most fruits have been modified for higher sugar content.

Add that to the excessive consumption of known sweets -- sodas, candy, etc. -- and Americans consume way too much sugar. That's the primary cause for obesity. Sure, it's calories. But sugar is the worst offender for empty calories that rarely satiate hunger.

And then there are the theories about how higher fat content foods may satiate hunger more effectively so people are less likely to overeat in general, or suffer blood sugar spikes and crashes that tempt them to eat more sugar.

Seattle Forrest

From the Journal of Nutritional Neuroscience:

Fat rather than sugar diet leads to binge-type eating, anticipation, effort behavior and activation of the corticolimbic system

For what it's worth, this is absolutely true in my case. The idea of eating a spoonful of sugar is revolting. Chocolate and iced cream, though, have more calories from fat than from sugar.

But other than protein being the most satiating macro by far, the rest is highly individual.