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Original poster

Calories in vs calories out is just not working !

220 replies

noseriouslyguys · 19/09/2025 17:28

Yes I know the principle is correct- I get it. But explain this to me then…

I’ve been weighing every bite I eat or drink for two months - PLUS exercising 5 times a week and I am not losing on the scale.

I have lost weight since the start of the year, without exercising at first, but now the scale is just standing still.

I create a deficit of 1000 calories a day and nada.

the scale teases me, it will say a certain low weight- then I get back on it and it says 2kg more the next day and it will show me that 2 kg more for another two weeks.

I have lost weight already by the way, without exercising since the start of the year- slowly. Maybe a kg a month- some months 2. I thought I would really tighten up my eating and track absolutely everything plus add in exercise. At first I thought it’s normal, water retention- but not after 2 months surely ?

I have gone to the gym a couple of times but mainly playing tennis. For 1-2 hours a day, 5 days a week. Sometimes 4. So it can’t be muscle gain from tennis.

anyway, I am not giving up- but it just makes no sense ?

I do agree with calories in vs calories out, but I have to drop down so extremely low- I mean 800 or so, to lose weight.

I currently eat between 1.200 and 1.500 a day ( max ).

OP posts:
Original poster
noseriouslyguys · 19/09/2025 19:33

UnhappyHobbit · 19/09/2025 19:32

This is why some people are on mounjaro!

I am !

OP posts:
Twinkylightsg · 19/09/2025 19:32

I have pcos and am like this. But by month 4-5 it starts melting off. Make sure u eat smaller portions throughout the day as opposed to larger portions as well.

Original poster
noseriouslyguys · 19/09/2025 19:32

i don’t have intense cravings.

OP posts:
UnhappyHobbit · 19/09/2025 19:32

This is why some people are on mounjaro!

InMyShowgirlEra · 19/09/2025 19:32

noseriouslyguys · 19/09/2025 19:30

Apple Watch is saying this week my most day it’s 2.900 calories and least active where I didn’t exercise it’s 2.300.

I estimate it should be at least 2000 a day with the amount I’m exercising and moving.

Ok well that's wildly incorrect unless you're 7 foot tall and built like a rugby player.

Original poster
noseriouslyguys · 19/09/2025 19:32

@realhousewifeofocyeah. Often.

OP posts:
Sundaymorningcalla · 19/09/2025 19:32

popcornandpotatoes · 19/09/2025 19:30

But the other side of this, the practical side, is women like op struggling to lose weight can't just keep relentlessly slashing calories to lower and lower amounts. It can cause all sorts of health issues and is miserable. So when 1200, 1000, 800 isn't working, something else may be going on with their bodies. Regardless of whether op thinks "she's breaking the laws of thermodynamics", it's not working so what else do you suggest?

Show quote history

The OP is eating too few calories then falling off the rails due to intense cravings and not tracking it, it's all to common, I see it with my clients all the time.

Original poster
noseriouslyguys · 19/09/2025 19:30

Apple Watch is saying this week my most day it’s 2.900 calories and least active where I didn’t exercise it’s 2.300.

I estimate it should be at least 2000 a day with the amount I’m exercising and moving.

OP posts:
Shitmonger · 19/09/2025 19:30

noseriouslyguys · 19/09/2025 19:01

But why do you need to know more than my TDEE ? It’s enough information.

Because your TDEE is wrong. The calculators always vastly overestimate it. Without your height and age this thread is pointless.

If you are 5’1” and 46 years old, for example, then needing to eat less than 1000 calories in order to lose weight is probably bang on.

bluecrochetedplane · 19/09/2025 19:30

If i were you I'd start again and get new scales.
Unless you're a gym addict I wouldn't use the calories burnt during exercise to alter the deficit amount, Id just have them as bonus loss.
It would be easier to get your deficit without guesstimating how much your burning from a watch.
Anyone who's actually in a deficit will lose weight, that's a fact. You're not in a defecit if you aren't.

popcornandpotatoes · 19/09/2025 19:30

InMyShowgirlEra · 19/09/2025 19:24

I'm saying that if you are burning more calories than you take in, you are going to lose weight. Your BMR will vary slightly depending on your hormones etc., but if it could just magically adjust to keep up with any diet, humans wouldn't be starving.

Most people in famine situations aren't eating no sustenance, they are not taking in enough calories to maintain their weight.

Show quote history

But the other side of this, the practical side, is women like op struggling to lose weight can't just keep relentlessly slashing calories to lower and lower amounts. It can cause all sorts of health issues and is miserable. So when 1200, 1000, 800 isn't working, something else may be going on with their bodies. Regardless of whether op thinks "she's breaking the laws of thermodynamics", it's not working so what else do you suggest?

realhousewifeofoc · 19/09/2025 19:29

noseriouslyguys · 19/09/2025 18:21

I eat two meals a day really. I weigh everything, no junk. I estimate I burn maybe 300 calories an hour for tennis, which isn’t that outrageous at all. That’s what my Apple Watch says anyway. But I low ball it. It estimates more than 300 calories.

I have done a lot of weight loss stuff in the past. I know I need to drop even lower in what I eat, but it’s ridiculous.

I eat under 1,200 on some days as well.

lots of days I don’t have breakfast ( well, I have a coffee and measure the milk ). I don’t have lunch and just have a lot of water with electrolytes and then I have chicken for dinner with potatoes or rice and broccoli. All weighed and measured.

other days I have coffee with milk ( measured ) for breakfast, Greek yoghurt with honey and fruit ( all measured ) and chicken or prawns with veggies for dinner. I don’t snack.

I really don’t eat a lot of food and I’m so careful measuring it because I really want to drop this weight.

What you've said you eat here sounds like it would come to less than 1200-1500 cals. Are you eating this way every single day?

Original poster
noseriouslyguys · 19/09/2025 19:26

Hellohelga · 19/09/2025 19:19

This has come up before. The tdee is an estimate and its on the high side. My tdee is 1800 for moderate activity and 1600 for light. I walk an hour daily and go to the gym three times a week. I reckon my maintenance is around 1400.

I’ve tried several websites and talked to ChatGPT about it. That’s the estimate on my TDEE. I am very active on top of that and I’ve been tracking my food intake religiously.

OP posts:
Sundaymorningcalla · 19/09/2025 19:25

Didimum · 19/09/2025 19:17

Who are you even talking to? OP is asking for advice and taking it on board. End of. Run along now.

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Didums, how appropriate.

Crikeyalmighty · 19/09/2025 19:25

I’ve varied this up a lot in last 6 months as originally did 6 weeks with mounjaro and then stopped - to consistently lose weight even at around a lb a week max I have to stick around 1150 to 1300 cals , keep salt down, drink loads of water and eat very little carb and no more than a couple of glasses of wine a week max . I’m 63, 5ft 4 and around 83kg - down from 96kg - it’s a hard slog - I walk around 10,000 steps a day plus an hour dance excercise class once a week. I find every few weeks if I up to 1600 cals for 2 or 3 days and then drop down again, that seems to help too if weight is stagnant .

InMyShowgirlEra · 19/09/2025 19:24

popcornandpotatoes · 19/09/2025 19:20

No, anyone can starve if they literally take in no sustenance. But are you suggesting that all.women struggling to lose weight should just starve as though they are living through a famine?

There's plenty of science our there about why weight loss is more than just calories in v calories out, just go and read it, it's not hard

Show quote history

I'm saying that if you are burning more calories than you take in, you are going to lose weight. Your BMR will vary slightly depending on your hormones etc., but if it could just magically adjust to keep up with any diet, humans wouldn't be starving.

Most people in famine situations aren't eating no sustenance, they are not taking in enough calories to maintain their weight.

Sundaymorningcalla · 19/09/2025 19:23

Northerngirl821 · 19/09/2025 19:12

The principle of CICO is false. Your body will vary your BMR to adjust to food supply, and hormones such as insulin and glucagon also influence your body’s ability to store or burn fat. If you reduce your calories as severely as you have, your body will crash its metabolic rate to compensate and then try to store any excess calories as fat in anticipation of further starvation conditions. If you then start to increase calorific intake, fat storage will increase too.

You need to read up on the science of metabolism if you want to calorie restrict effectively!

This is the biggest myth going, starvation mode doesn't exist. You can't defy the laws of thermodynamics. As you lose weight your TDEE decreases, if that's what you mean by metabolism changing?

soupyspoon · 19/09/2025 19:22

You could do a couple of experiments OP, first month you do 1200 a day, averaged over the week obviously, focusing on low fat, second month the same calories but focusing on higher protein and fat. See if one is more effective than the other. Personally I need to eat quite a lot of fat and cut wheaty type foods and non veg carbs and that really drops me down but only if I stick to the right calories, if I don't eat enough fat I get too picky, hungry and bloated

soupyspoon · 19/09/2025 19:22

You could do a couple of experiments OP, first month you do 1200 a day, averaged over the week obviously, focusing on low fat, second month the same calories but focusing on higher protein and fat. See if one is more effective than the other. Personally I need to eat quite a lot of fat and cut wheaty type foods and non veg carbs and that really drops me down but only if I stick to the right calories, if I don't eat enough fat I get too picky, hungry and bloated

popcornandpotatoes · 19/09/2025 19:20

InMyShowgirlEra · 19/09/2025 19:17

By that logic, everyone living in a famine would be fat.

Show quote history

No, anyone can starve if they literally take in no sustenance. But are you suggesting that all.women struggling to lose weight should just starve as though they are living through a famine?

There's plenty of science our there about why weight loss is more than just calories in v calories out, just go and read it, it's not hard

Hellohelga · 19/09/2025 19:19

This has come up before. The tdee is an estimate and its on the high side. My tdee is 1800 for moderate activity and 1600 for light. I walk an hour daily and go to the gym three times a week. I reckon my maintenance is around 1400.

Didimum · 19/09/2025 19:17

Sundaymorningcalla · 19/09/2025 19:09

This is the sort of narrative a loser peddles whose not committed to lifestyle change to lose weight..

Go back to weapons world and continue to receive terrible advice and create bad habits and relationships with food.

Show quote history

Who are you even talking to? OP is asking for advice and taking it on board. End of. Run along now.

InMyShowgirlEra · 19/09/2025 19:17

Northerngirl821 · 19/09/2025 19:12

The principle of CICO is false. Your body will vary your BMR to adjust to food supply, and hormones such as insulin and glucagon also influence your body’s ability to store or burn fat. If you reduce your calories as severely as you have, your body will crash its metabolic rate to compensate and then try to store any excess calories as fat in anticipation of further starvation conditions. If you then start to increase calorific intake, fat storage will increase too.

You need to read up on the science of metabolism if you want to calorie restrict effectively!

By that logic, everyone living in a famine would be fat.

InMyShowgirlEra · 19/09/2025 19:16

So considering that the BMR for the average woman is around 1500 calories and you're adding 300 for tennis, you're trying to say that you eat 800 calories a day and have the energy to play tennis for 4 hours?

Original poster
noseriouslyguys · 19/09/2025 19:16

Northerngirl821 · 19/09/2025 19:12

The principle of CICO is false. Your body will vary your BMR to adjust to food supply, and hormones such as insulin and glucagon also influence your body’s ability to store or burn fat. If you reduce your calories as severely as you have, your body will crash its metabolic rate to compensate and then try to store any excess calories as fat in anticipation of further starvation conditions. If you then start to increase calorific intake, fat storage will increase too.

You need to read up on the science of metabolism if you want to calorie restrict effectively!

So what’s the answer ? Because when I drop low enough, it does end up working.

OP posts: