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1

Sketti_n_butter t1_j2a4lgj wrote

It's good. Systolic pressure is the higher of the two. When that is lower, your arterial system is operating at a lower pressure, which likely leads to less long term damage. The key takeaway is that the effects are likely due to weight loss.

38

Applejuiceinthehall t1_j2a6ujq wrote

It just means that there should be some studies comparing IF to weight loss without IF.

The studies in the meta analysis only had a control group that ate normally but a losing weight group (like calorie deficit).

Then we can see if it's just weight loss or if IF is improves more blood pressure than weight loss alone.

Also, it says that there was no improvement in lipid levels or heart rate.

Also, "(1) the participants included mostly adults with metabolic diseases such as obesity."

So the benefit for overweight or normal weight people might be small or non-existent.

51

BafangFan t1_j2aas1c wrote

Here's my take: your hormones are supposed to be in some form of balance. With modern diet and modern lifestyle, our insulin levels are too high for too much of the day. When you become insulin resistant, your blood insulin levels remain higher for longer.

High insulin levels on their own are damaging to tissues.

Intermittent fasting allows time for insulin levels to come down to safer levels. Eating 6 small means throughout the day, or snacking between meals and late at night, keeps insulin levels too high for too long.

76

BafangFan t1_j2ad1tx wrote

As someone who is insulin resistant and wears a continuous glucose monitor, even low GI foods raise blood glucose, and therefore insulin.

The only food that doesn't raise insulin levels is fat (and maybe alcohol).

Every carbohydrate gets converted into sugar (glucose), as far as our cells are concerned.

16

aliceroyal t1_j2ahqy1 wrote

I have PCOS with insulin resistance. I can only do IF when medicated with an appetite suppressant but it works pretty well--I see it as a kind of harm reduction, if my body is going to crave calorie-dense food, might as well restrict the amount of time I eat so I'm putting less calories in overall.

13

Explicit_Tech t1_j2aloo7 wrote

I've been doing intermittent fasting for a long time, maybe almost a decade. It was never for a caloric deficit since I still make up for it 1-2 big meals later. The beneifit was not having the need to constantly raise my insulin levels, which would either make me more hungry or more tired from eating carbs in the morning. What I do now has reduced a significant amount of the fat around my belly area. Was still able to obtain gains too in muscles.

7

Wiggen4 t1_j2alqmo wrote

So the interim takeaway for the public is that intermittent fasting does not seem to be an overly risky form of weight loss. If you have high blood pressure, find a diet format (that isn't dangerous) that will be the most sustainable for you. Weight loss and financial success are majority behavioral, you just have to find the right systems to set you up for success

9

aliceroyal t1_j2amem0 wrote

So it's Ozempic, which does help with blood sugar along with the appetite suppression. It was originally a diabetes drug before celebrities figured out they could use it to lose weight lol.

6

VicodinMakesMeItchy t1_j2auzbv wrote

I suppose my “hot take” would be that after you’ve fasted for more than 12 hours, you have burned off any glucose plus all of the glycogen stored in your liver. There is no longer any form of carbohydrate to derive energy from, so the body directly mobilizes fat stored inside adipocytes. That produces ketones in the body, which have been shown to have their own beneficial effects.

Eating all day at a calorie deficit will slowly chip away at the fat, but it’s less effective because energy for the missing calories are taken from a constantly-replenished glycogen store, plus some from fat cells. Removing the glycogen store in the liver through fasting and forcing fat cells to provide all of the energy instead, means your calorie deficit is being taken directly from fat stores. Remaining in the glycogen-depleted state for a few hours per day means more fat is burned through for energy in total.

Adding in the fact that excess glycogen stored in the liver is converted into fat and stored in adipocytes, the less glycogen you have overall, the smaller the fat stores in adipocytes will be, and therefore overall weight.

27

RtuDtu t1_j2ay47n wrote

it gets to a point where you don't want to eat breakfast as it makes you feel bloated. Once I started after a few weeks I couldn't stop even if I wanted because I don't like how I feel when I eat breakfast

44

D74248 t1_j2b26fr wrote

Here's my hot take.

I listen to my doctor. It helps that a family member in academic medicine tells me that her guidance is in line with recent studies. And by following my doctor's guidance I diet control my T2 diabetes into an A1C in the low to mid 5s. I am now considered by the ADA to be in remission. I didn't get here with CICO.

Intermittent fasting lowers insulin levels.

13

VergesOfSin t1_j2b2buu wrote

Its not that simple. It lowers insulin and keeps it low for hours. That's where a bunch of the benefits come from.

A calorie restricted diet would have you eat 6 small meals a day. That means your insulin never gets a chance to hit basr level, and you'll feel ravenous the whole time.

It is significantly easier to just not eat, than it is to eat less.

12

SKDI_0224 t1_j2b34y5 wrote

I lost 100 pounds and yeah, IF was part of it.

11

TV11Radio t1_j2b4z3o wrote

Do NOT be like me and celebrate losing 50 by thinking you can eat anything for the next year and losing progress. Please keep it up or be making a new years resolution tomorrow like me :(

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WantedDadorAlive t1_j2b8wdf wrote

Been doing 16:8 since mid August and it's amazing. Down nearly 50 lbs and never felt better. Lots of water, black coffee or tea is hugely helpful those first couple weeks but you get to a point you just aren't hungry during your fasting window.

2

chadwicke619 t1_j2b9ps1 wrote

You’re missing the point. You’re body doesn’t keep track of time in the same way that we do. People who fast stop eating at, say, 8PM. At that time, their body has plenty of glucose to work with, plus there is insulin present. As you get further away from your last meal, you have less and less insulin, and less glucose just floating around, and this applies to everyone. Now, most people wake up and eat, replenishing this glucose that is floating around. Not people who fast, though. They keep on going, until the body just has to start chipping away at fat. People who don’t fast never dip into this zone where they are just walking around, burning fat - they keep the store replenished. People who fast spend a few hours a day in this zone.

5

whichonespink04 t1_j2bchdy wrote

Yeah, unfortunately this study tells us exceptionally little and doesn't really support intermittent fasting per se--though it certainly doesn't detract from it--primarily because it was compared to normal diet and so there's no way to attribute the blood pressure improvement to the diet versus the weight loss. It would be interesting to compare to average changes in systolic blood pressure with similar weight loss. Incidentally, this paper is pretty damn embarrassing in that it literally never (as far as I can find), not even once, mentions what unit the damn weight is measured in (nor any of the other measures except once to say mmHg). It kind of makes a big difference between pounds and kilograms. I presume it's kilos, but how hard is it to put the unit in a couple times? Hard to say if the weight difference is considered clinically significant too because the studies ranged in length from 1-12 months.

I'm not saying don't try it or it isn't helpful for people, but this doesn't add much or anything to support its use.

4

CougarAries t1_j2bck2r wrote

I loathe breakfast since starting IF like 10 years ago. I'm not hungry when I wake up, and if I eat something, I get hangry 3 or 4 hours later.

After getting used to skipping breakfast, Im now not hungry until like 2 or 3pm. And not ravenously hungry, but more like, "I guess I could eat something."

Unfortunately, I'm getting old enough (Late 30s) where IF isn't enough to keep the weight off alone anymore. I guess I need to work out too now.

14

Djappaman t1_j2bdhnd wrote

Is this fasting for atheists?

−1

HolyStoic t1_j2bn1ov wrote

I’ve been accidentally intermittent fasting and I’ve dropped like 10 pounds this past month. I can’t gain weight back.

2

VergesOfSin t1_j2bqsxq wrote

Get electrolytes. Sea salt and potassium citrate. 1 to 2 ratio. Flavor the water anyway you want as long as its 0 calorie.

If you can't get the potassium just salt will be fine. Try to eat extra potassium if possible.

2

calumin t1_j2bwgiq wrote

I don’t know that anyone thinks IF has any significant intrinsic benefit other than its ability to facilitate weight loss. What would the point of IF be if not to facilitate weight loss?

2

VicodinMakesMeItchy t1_j2bysat wrote

Of course your metabolism has no idea what time it is. It doesn’t matter what time it is—after 12 hours of fasting, you have burned through your glycogen stores. It’s literally just biochemistry.

Get off your bro science high horse. You clearly don’t know as much about metabolic processes as you think you do.

2

mr_doppertunity t1_j2c4418 wrote

Why IF works for weight loss: caloric deficit.

Why keto works for weight loss: caloric deficit.

Why %dietname% works for weight loss: caloric deficit.

Why does IF improve health: you lose excess weight and your health markers get back to normal.

Why does keto improve health: you lose excess weight and your health markers get back to normal.

Why does %dietname% improve health: you lose excess weight and your health markers get back to normal.

Yet another study supports this claim.

Mostly, there’s really nothing more to add to it. People often forget that correlation doesn’t mean causation and give diets some exceptional qualities, while the effects they see are caused by the mere fact they lost weight. And you can lose weight on beer and ice cream (literally) and still improve your health.

IF is merely a timing protocol, for the most people it’s primarily helpful to control hunger and to not dive deep into counting calories (as satiety is achieved faster by having larger meals in smaller time window), maybe some can benefit from keeping insulin levels low. That’s all.

So eat a balanced diet, lose excess weight and improve your health markers, but it’s up to you whether to follow IF.

P. S. I see posts like “eating 6 meals bad”, but I can eat 8 meals while doing IF (I guess I’m always in postprandial state while not fasting), so there’s absolutely no relation between those.

−1

NotLunaris t1_j2c5xqa wrote

My hot take: calories in; calories out is not the end-all be-all of dieting and weight loss. People like to quote the first law of thermodynamics as if the human body operates in a vacuum. Truth is, not all the calories we take in get absorbed by the body. There is the basal metabolic rate, which differs for everybody and can fluctuate day-to-day, as well as the condition and makeup of the gut biome breaking down certain foods and making them more bioavailable. The ability of the stomach to break down foods, and the intestines to absorb them - so many factors determine how many nutrients one can absorb from the food they eat.

It is, therefore, not outlandish - not even anything special, really - to suggest that there is more to weight loss than calories in, calories out. We already know that hormones can have a significant impact on how much fat one is able to gain/lose on the exact same diet in patients with hyper/hypothyroidism. Perhaps IF puts one's body in a state to lose more fat compared to someone who is eating three square meals a day. Perhaps it's not purely calories.

More research is needed, and this is just my humble opinion.

2

bisforbenis t1_j2cbfw4 wrote

It means Intermittent fasting is good for lowering systolic blood pressure, but doesn’t do much for diastolic blood pressure. Systolic blood pressure is more strongly correlated to all sorts of health problems (both matter, but systolic matters more barring edge cases) so this is good

However, it’s basically saying that there isn’t some magical thing going on with intermittent fasting specifically, the only reason it’s good for lowering systolic blood pressure is because it’s good at helping you lose weight, but it’s no better at reducing systolic blood pressure than any other approach to weight loss

7

byneothername t1_j2ccdte wrote

I personally saw my A1C go down while I was intermittently fasting. Don’t know if there are studies on that and I don’t know how to distinguish that from generally keeping my weight down.

5

RoseBengale t1_j2cft6n wrote

Totally non-scientific personal anecdote: IF really exacerbated my binge eating/exercise bulimia and I ended up gaining so much more weight than I had lost. Might not be the best route if you suffer from disordered eating.

12

T6000 t1_j2cjjww wrote

No, I'm not missing the point. Intermittent fasting is just another fad diet that people hope will put them in a caloric deficit. I'd rather eat when I feel like it and still lose weight if I chose to by eating low calorie dense food. Most people won't find sustainability in intermittent fasting or keto.

−4

Wants-NotNeeds t1_j2cmtbr wrote

Before they term “intermittent fasting” was a thing I used to fast once a month. I’d eat a healthy dinner by 7pm, and not resume eating for about 36 hours. (A one day fast, 1x month.). Would that be considered “intermittent fasting” by today’s standards? I always felt good afterwards.

3

J11ghtman t1_j2cs243 wrote

IF is interesting because while it definitely has benefits, I have no idea if they’re specific to IF or incidental to the fact that you’re consuming fewer calories in general when you’re fasting. Like IF has obvious benefits, but are they superior to the same level of caloric restriction spread over three meals throughout the day?

Put another way, if I am going to eat 1,400 calories in a 24-hour period, does it matter if I only eat them between 8am and 2pm, vs. any time in that 24-hour period?

I think the only consistency in IF studies is that it works, but not because of IF science—it’s just another way of caloric restriction dieting that requires less planning and fewer temptations.

1

J11ghtman t1_j2csf4w wrote

The easiest way to get in shape is to ask yourself “did I move enough this morning/afternoon/evening?” Every day and also “is what I am planning to eat this morning/afternoon/evening/right now healthy?”

People know the answers to both of these questions. If you’re overweight or have high cholesterol the answer is usually “no” to both of them. The challenge is motivating yourself to eat well and exercise. IF is great, dieting is great. The problem is that they are always temporary solutions to a willpower and lifestyle problem that needs to be addressed to see lasting success.

7

lurkerfromstoneage t1_j2csfpp wrote

Do NOT toy with intermittent fasting if you (or a dependent child) are suffering or have wrestled with an eating disorder.

12

calumin t1_j2cshr8 wrote

That’s great!

I also had some very positive effects from IF. I’m just not sure I would have expected IF, on its own, to have affected my blood pressure, or any other statistic, without considering IF in combination with actual dietary choices.

1

LuckyHedgehog t1_j2d75qk wrote

When your body enters a fasting state it will begin a process called Autophagy, the process of cleaning up old and damaged cells in your body

This process has a number of beneficial long term effects such as lowering cancer risks, elimination of latent viruses and pathogens hiding in older cells, triggering stem cell production, etc.

Another study about this effect, though this is using longer fasting cycles the benefits still apply for IF

https://news.usc.edu/63669/fasting-triggers-stem-cell-regeneration-of-damaged-old-immune-system/

>The study has major implications for healthier aging, in which immune system decline contributes to increased susceptibility to disease as people age. By outlining how prolonged fasting cycles — periods of no food for two to four days at a time over the course of six months — kill older and damaged immune cells and generate new ones, the research also has implications for chemotherapy tolerance and for those with a wide range of immune system deficiencies, including autoimmunity disorders

2

LuckyHedgehog t1_j2d7z42 wrote

It's far from definitive, but here's an article on Diabetes.co.uk

>A study published in February [2017] reported that cyclical fasting helped to repair beta cells in mouse models of type 1 diabetes. This may be due to the fact that autophagy is often followed by a massive boost in stem cells that can replenish or replace beta cells destroyed by autoimmune processes with healthy cells

1

whatisitmooncake t1_j2da3ce wrote

Hot take that is purely wrong. Fasting causes a cascade of changes in the body that affect stuff all the way down to mitochondria. When the body has to switch from glucose to ketones for fuel... it's a big deal.

0

Ashamed-Simple-8303 t1_j2ddjj9 wrote

In terms of weigh loss, moving/exercise plays a very minor role. Even if you believe the myth of calories in, calories out, the calories burnt by exercise are minuscule compared to energy needs just for staying alive.

What really, really matters first is what you eat and not how much you eat. Because if you eat right and get your hormones (mostly but not only insulin) in control, your hunger and cravings will go down, a lot. You will automatically eat less. Eg. you then don't even need the will power as you will stop being hungry all the time.

Exercise helps somewhat mostly because it helps to deal a little bit with the poor western diet but not by burning calories but by affecting your metabolism.

5

Ashamed-Simple-8303 t1_j2deppk wrote

> Unfortunately, I'm getting old enough (Late 30s) where IF isn't enough to keep the weight off alone anymore. I guess I need to work out too now.

Not really. exercise is almost irrelevant in terms of energy burnt. I still advise to work out as in strength training combined with functional training (eg balance). building muscle will only get harder with age and it will help a lot with common problems at age especially better balance. More muscle also means more calories burnt when sleeping or watching TV.

What you really need to address is not how much you eat and exercise but what you eat. And here the common advice is usually just poor or even outright harmful, namley low fat. low fat it terrible because it means high carb which means high insulin response. And insulin makes your body store fat and prevent fat from burning.

Second issue is that high fat is too general. You need to go high saturated fat (eg animal fats mostly). mono-unsaturated (olive oil) to an extend is also ok but for sure avoid any highly processed plant oils. polyunsaturated fats (eg. plant oils aka PUFA) are THE cause for arteriosclerosis (full biochemical pathway is pretty much known). The problem is that we feed your animals "crap" especially pigs and chickens but also farmed fish like salmon. So these meats usually also contain too much PUFAs and need to best be avoided. what remains is meat from ruminants that ate gras (beef, sheep/lamb, venison).

What you must avoid under all circumstances is any deep fried food most notably french fries. the repeatedly cooked plant oils used fir frying in most places are unstable and result in toxic products which the deep fried food is drenched in.

0

Sculptasquad t1_j2dh0nf wrote

Massive volumes of matter passing through your colon and rectum is directly associated with an increased risk of rectal issues such as fissures, tearing, hemorrhoids etc.

Compare passing 500 grams of waste twice a day to passing 2 kg once every two days.

−2

kerridge t1_j2dhoj4 wrote

Although there is likely an association, this will be due to lack of fibre, for example not eating enough vegetables with food. As a vegetarian, I have done massive shits all my life and suffer with zero such issues. If the mass is impacted but if you eat enough fibre it's gonna be absolutely fine. and the time to recover is absolutely going to help. Stop spreading faecal related FUD!

1

Fumobix t1_j2dsk1a wrote

Pretty sure i've read that IF is good at many things but not at weight loss, so this study is affirming that IF is good for weight loss?

1

StevenTM t1_j2e198b wrote

IF works just fine for people over 40, what on Earth are you on about?

Edit: and no, a "slowing metabolism" is not a thing that exists before your 60s, on average, and it's not the reason people gain more weight in middle age (late 30s - early 50s), or have more trouble losing it. Barring medical conditions, your metabolism slows at a predictable rate, but is mostly stable between age 20-60.

https://www.health.harvard.edu/blog/surprising-findings-about-metabolism-and-age-202110082613

> these results strongly suggest we may no longer be able to blame weight gain in middle age on a slowed metabolism.

4

whichonespink04 t1_j2e1yb5 wrote

I don't think it's quite that simple, but I do think that calorie deficit is the central factor for weight loss in most diets. I do think there is some role for timing and body state in the efficiency with which someone absorbs calories and how they metabolize them that can produce an effective calorie deficit between calories invested and calories that are usable and I think some diets capitalize on that. There may be some role of body-integrated calorie catabolism during ketosis states, but I'm less sure of the legitimacy there and haven't read enough to really know.

2

LuckyHedgehog t1_j2e2bo7 wrote

Going that long is extreme and should definitely be medically supervised to make sure you're getting the correct nutrition supplements. People do go that long on a routine as well but they have to build up to it and be very careful coming out of it to avoid refeeding syndrome

In this context they're looking at the extreme specifically for treating cancer patients

2

CougarAries t1_j2efqeu wrote

Just stating my own personal experience. Maybe if you're over 40 and you want to drop some weight IF works, but I've been on IF for a long time now, so my goal hasn't been to lose weight, but just to maintain. And I don't know if you know this, metabolisms slow down pretty noticably by the time you hit 40, so maintaining weight requires a little more effort than when you're 30.

−1

StevenTM t1_j2ehvyb wrote

I am aware.. that it's mostly pseudoscience. "Metabolism" refers to basal metabolic rate. From the Mayo Clinic:

> Metabolism is the process by which the body changes food and drink into energy. During this process, calories in food and drinks mix with oxygen to make the energy the body needs. The number of calories a body at rest uses to do these things is known as basal metabolic rate, also called basal metabolism.

BMR differs by 100-200 kcal per day between a 25 and a 55 year old who are both 180cm/6" and 80kg/176lbs (declining with age). It differs by 300 kcal per day for those doing a lot of exercise.

https://www.calculator.net/bmr-calculator.html

Harvard also disagrees with your statement:

> Adulthood (20 to 60 years): Total and basal expenditure and fat-free mass were all stable from ages 20 to 60, regardless of sex.

> What’s more, these results strongly suggest we may no longer be able to blame weight gain in middle age on a slowed metabolism.

https://www.health.harvard.edu/blog/surprising-findings-about-metabolism-and-age-202110082613

2

CougarAries t1_j2ezpcx wrote

And 100kcal a day excess equates to a pound gained every 20 days or 18 lbs a year.

That's some fascinating research though that changes a lot of preconceived notions about aging.

Either way, my religiously followed 18:6 fasting schedule that I've followed for 10 years isn't enough to keep maintenance anymore, and whether that be diet or activity related, I can no longer rely on just IF and need to supplement it with some other form of lifestyle change no matter how you argue it. I'm definitely significantly healthier going into 40 because of it, but it's not a magic bullet that solves everything.

1

just_tweed t1_j2f3fna wrote

NEAT, however, might change. I'm eating the same or less, workout more than I used to, but I've gotten 10kg fatter over the last 20 years or so. I just spontaneously move a lot less, and have less energy overall.

1

StevenTM t1_j2f8f4u wrote

That (100-200) was the difference between 25 and 55. The difference between 25 and 35 is at most 60 kcal. 60*365/7000=3.129 kg gained per year if you consume a fixed amount of calories daily every day, but almost nobody does. So if you maintain the same activity level, you'll just naturally need a bit less. If you count calories, run a BMR calculator using updated values every 5 years.

IF helps you lose weight by reducing cravings and snacking. You still need to apply CICO, IF just makes it easier to do so. I guarantee that if you consume the exact amount of calories that is required for your daily lifestyle (say 2350), you will neither lose, nor gain, weight, regardless if you eat 8 meals a day or OMAD.

Again: IF helps with cravings and hunger. You need to reduce your caloric intake (relative to body weight) as you age, but not by a lot. But obviously a 30 year old should neither be consuming as much as they were when they were 17, (and super active/developing) nor should they continue consuming as much when they're 70 as they did when they were 24, when they're likely to be way more sedentary.

1

StevenTM t1_j2f9usi wrote

And you seem self-aware enough to know that that's a factor, but still don't compensate for it by eating less or exercising more. I'm not sure what to do with that information tbh

1

amoose-boosh t1_j2fezzj wrote

Do what works for you, what works for some doesn’t work for all. But IF is no more of a fad than the three meal a day diet which most of us follow. For most of human history meals came sporadically - it’s relatively easy to stick to because our physiology evolved to handle it. I’ve personally done IF (OMAD) and stuck with it for over a year.

1

just_tweed t1_j2fhm94 wrote

Well, it's something that people miss or misunderstand when they talk about "metabolism slowing", that it's actually probably NEAT and/or just becoming more sedentary in general. A good thing to remember as you age.

1

CougarAries t1_j2fsh7w wrote

That's my point, is that focusing only on a IF schedule was previously enough to initially lose then later maintain weight, and now I need to do a little more, including tracking CICO which I never previously had to do.

1