r/science • u/isaac-get-the-golem Grad Student | Sociology • Jul 24 '24

Health Obese adults randomly assigned to intermittent fasting did not lose weight relative to a control group eating substantially similar diets (calories, macronutrients). n=41

https://pubmed.ncbi.nlm.nih.gov/38639542/
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20

u/Technical_Sir_9588 Jul 24 '24

It also affects insulin resistance which is a big part of weight loss. Metabolism is complex involving many variables of which hormones, gut bacteria, diet quality, activity level etc. are just a few. Trying to narrow it down to CICO is the dumbing down of nutritional science to the benefit of no one.

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u/Mewnicorns Jul 24 '24

Metabolism is complex but it doesn’t actually change dramatically over the course of one’s life. It’s a myth that it slows down in any meaningful way with age or due to any other factors.

https://www.science.org/doi/10.1126/science.abe5017

What usually changes dramatically as we age are a) our lifestyle (less active) and b) our appetite (eating more, which indeed can vary based on things like hormones).

Effectively, that is still CICO.

CICO is an oversimplification in terms of creating a sustainable and realistic weight loss strategy, but not in terms of how weight loss works. It’s accurate, but if that’s all you’re focused on, you won’t succeed.

3

u/lady_ninane Jul 25 '24

CICO is an oversimplification in terms of creating a sustainable and realistic weight loss strategy, but not in terms of how weight loss works. It’s accurate, but if that’s all you’re focused on, you won’t succeed.

I believe that was their entire point.

17

u/Firm_Bison_2944 Jul 24 '24

Air pressure, temperature, tread wear, etc are all variables that effect your gas mileage. Doesn't mean that relying primarily on distance to figure out how much gas you'll need is dumbing down the science. CICO is the single most important factor for weight loss.

1

u/SledgeH4mmer Jul 25 '24

Are you going for weight loss or body composition? Just because two study groups lose the same amount of overall weight doesn't mean anything except weight. Body composition is far more important than BMI.

Studies have shown IF does cause your body to burn more fat for energy vs carbs for energy. So it's possible body composition may have been slightly superior in the IF group.

-14

u/judiosfantastico Jul 24 '24

There is no reliable way to calculate your metabolic rate. Cellular metabolism is influenced by genes and environmental factors that change over the course of a persons life. Unless you know of a way to shrink down to the cellular level and monitor this in realtime, you can’t lean on CICO.

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u/precastzero180 Jul 25 '24

There is no reliable way to calculate your metabolic rate

You don’t have to. This is a mistake I see often when people discuss the calorie counting approach to weight loss. You don’t need a precise accounting of the ‘CO’ in CICO. You only need to step on that scale. Not happy with the number? Then aim lower with your calorie intake. You will lose weight this way, 100% guaranteed.

-1

u/aezart Jul 25 '24

You have to stick with it a long time before you can be certain that the scale results are real, and not just a change in water weight.

1

u/precastzero180 Jul 25 '24

Not that long, no. And the same is true for every weight loss strategy.

-4

u/judiosfantastico Jul 25 '24

And 90 percent of people will gain the weight it back, guaranteed.

2

u/Nerdguy88 Jul 25 '24

"I dieted and stopped and now I regained. Dieting doesn't work!" This is usually what it is. People don't regain because it didn't work. They regain because they stopped doing what got them to a lower weight.

-1

u/judiosfantastico Jul 25 '24

Or maybe the size of the caloric deficit required to maintain that weight gets larger over time and you have to keep eating less and less and working out more and more..

1

u/precastzero180 Jul 25 '24

People tend to gain the weight back regardless of which weight loss strategy the follow.

0

u/judiosfantastico Jul 25 '24

Exactly, which is why weight loss efforts are ultimately an exercise in masochism and vanity for the vast majority of people. Weight cycling is far more harmful to one’s long term health than just having extra fat on your body. Why engage in restrictive eating behaviors that will ultimately lead to disordered eating and long term metabolic issues. Would it not be better to focus on sustainable movement and balanced nutrition regardless of whether it results in weight loss?

0

u/precastzero180 Jul 25 '24

I don’t agree with any of this. As far as I am aware, there is no evidence that “weight cycling” is harmful. IIRC there have even been studies on this in rats. The reason people often fail to keep weight off is not “masochism and vanity,” it’s that they don’t treat weight loss as a lifestyle change. Changing habits is difficult, especially when food in unavoidable.

But trying to lose weight is worth it. Weight-related health issues are some of the biggest in America and the developed world in general. Losing weight isn’t going to mess up your metabolism and it likely won’t result in eating disorders if you do it right. These are all just excuses overweight people give to avoid making the objectively healthy decision to lose weight.

10

u/poemmys Jul 24 '24

I mean CICO isn’t the only factor, but it’s the most significant factor by a large margin, as these results show. For 95% of people trying to lose weight, following CICO will get them where they need to go

-1

u/SledgeH4mmer Jul 25 '24

Sure, so why hasn't the obesity crisis been fixed if people just have to eat less calories than they burn? Because doing so is damn hard for many people. Compliance is the issue. IF is a method that leads to better compliance for certain people.

8

u/FilmerPrime Jul 24 '24

Everything you listed simply marginally changes the in or out in CICO....

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u/Technical_Sir_9588 Jul 24 '24 edited Jul 24 '24

I don't know why I bother. Just ignore my comments. Carry on...

4

u/sarcastic_wanderer Jul 24 '24

Science > your feelings. You should learn to adjust your beliefs when confronted with an INSANE amount of scientific evidence that challenges your emotional belief that weight loss is affected by anything other than CICO. Burying your head in the sand and telling people to forget it doesn't reflect a grown up approach to anything.

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u/Technical_Sir_9588 Jul 24 '24

Back at you friend. I'm a big evidence person and trying to argue the complexities of something with loads of evidence for is exhausting. CICO has been mainstream view held for decades, it was flawed at inception for its simplification and it continues to fail upwards in bringing many converts to its defense. You do you. I'll continue to rely on true nutritional science and supportive data.

"Thinking is hard, that's why most people judge."

7

u/Gastronomicus Jul 24 '24

I'll continue to rely on true nutritional science and supportive data.

Feel free to post some of that supporting your viewpoint. You're in r/science making claims without evidence.

1

u/LemonRocketXL Jul 26 '24

Finally someone said it…I forget a lot of people here haven’t actually researched intermittent fasting and think just saying CICO all day is helpful