Why 1000/1200 calorie diets are bad - backed by science

daj150

I've been eating 1300-1400 cals per day and eating my exercise cals back as well... exercise is a combination of strength 3 days per week with cardio (usually swimming), and another 2 days a week just cardio... my goal right now is to decrease fat while maintaining as much lean body mass as I can in the process... once I get my bmi down to a healthy range, I'll up my cals and start working towards the more fit look... hoping this is a good process lol, its working so far it seems

I would ditch BMI ...according to BMI I am "obese" but have 13% body fat..how does that work..???

You are one fat ripped dude!

Hexahedra

One thing that stands out from the first study is the average 454 calories decrease in the TDEE of people in -25% caloric restriction group after 3 months. This means that the slowed metabolism would fully counteract the -25% caloric deficit if your starting TDEE is less than 1816, resulting in the dreaded plateau.

Let's say a sedentary person's TDEE is 2000 calories. A 25% caloric reduction would put him on a 1500 calories diet. If that 25% reduction ends up slowing his metabolism to 1546, he only has effectively 54 calories of deficit, which is barely perceptible and can easily be negated by miscounting a couple of tablespoons of sugar.

The most important point is that you can combat slow metabolism through exercise.

I don't know how much of the lowered TDEE was slowed metabolism, and how much was just that people didn't expend as much energy when they ate less. I'm not talking about exercise (as this was the non-exercise group), but maybe generally just moving about.

I've noticed that when I was younger my weight maintained within a couple of pounds for years even when my activity levels varied wildly. I've always thought that was because if I moved about more I naturally felt hungrier and instinctively ate the right amount to maintain. But perhaps it works the other way round too - the less you eat, the less you feel like moving around - instinctively maintaining again.

But yes, either way, I think it might help to explain plateaus.

My personal experience, which included fasting at some point, shows that when I'm in a large caloric deficit I tend to be lethargic and therefore move less. At some point I actually tried very hard to stay awake, as my body just wanted to shut down due to lack of energy. Nothing slows down your metabolism like sleep.

BluejayNY

I honestly never noticed a difference with losing weight with or without exercising. If I work out, then I naturally get hungrier and end up eating the calories I burned. I am not saying I am pro sitting on your butt starving yourself, but just that I haven't noticed a real difference.

55in13

The study shows that the group that did both calorie restriction and exercise did not see any reduction in their TDEE.

The majority of posts I see claiming to have hit a plateau are made by people who claim to be exercising. MFP posters who openly say they are not exercising are pretty rare.

bcattoes

I honestly never noticed a difference with losing weight with or without exercising. If I work out, then I naturally get hungrier and end up eating the calories I burned. I am not saying I am pro sitting on your butt starving yourself, but just that I haven't noticed a real difference.

That doesn't mean that's true for everyone, though. I didn't change my eating habits at all to lose weight. I just started exercising regularly again. I didn't count calories or log anything. Just got my lazy bum up and moved. I dropped 2 dress sizes (my goal) in 5 months.

emmythedagger

Well, I for one enjoy reading about what the science says. Sure 1200 diets might work for some people, but I would rather concentrate on getting physically fit and strong rather than how much I weigh. I recently upped my calorie goal from 1200 to my BMR. I joined a gym to start some strength training and I'm trying to eat more protein and eat my exercise calories back. I am a little concerned that my weight loss will slow way down (I was really happy with my 20lb loss), but I'd rather be able to run a marathon than say I only weigh so-many lbs.

Thanks for answering a few of the questions that I didn't know how or who to ask.
I have a few more if anybody wants to dive in. I'm very new to this.
-How can I gain muscle but make sure I don't put any fat on?
-What strength training should I be doing? I use the machines at the gym. A little of everything, or concentrate on building up weight on one machine?
-Where can I get protein without fat?
-How much should I eat back without getting fat?

jonnythan

Thanks for answering a few of the questions that I didn't know how or who to ask.
I have a few more if anybody wants to dive in. I'm very new to this.
-How can I gain muscle but make sure I don't put any fat on?
-What strength training should I be doing? I use the machines at the gym. A little of everything, or concentrate on building up weight on one machine?
-Where can I get protein without fat?
-How much should I eat back without getting fat?

1) Impossible. If you are gaining weight, you are gaining fat. You can make sure you are gaining as much muscle as possible in relation to fat by gaining slowly and weightlifting.
2) Quit the machines. Use freeweights. Look at Stronglifts. It's much faster, more effective, and more efficient.
3) Lean meats and protein powders. Chicken, fish, turkey, whey, casein, blends, etc.
4) I'd recommend a mild calorie surplus - on the order of 200 calories over TDEE.

55in13

The study shows that the group that did both calorie restriction and exercise did not see any reduction in their TDEE.

An interesting point about this, assuming I understand this and the point the OP was making. If I didn't exercise and my TDEE dropped to 1500 (2000 - 25%) then 1200 would give me a 300 calorie deficit or 2100 a week, still losing over a half pound. Add in my running, currently 20 miles a week, and it would go to about 4500 except that if that kicks the metabolism back up to 2000 a day I get 3500 more and would be be losing over 2 lbs a week. Sure enough, here we are 24 weeks into the year and I have lost 48 pounds. It has not been linear, though. My sedentary TDEE was higher when I had to haul 2 cases of butter around with me all day...

skinnydreams19

Agreed, when I eat less I'm too tired to even peel myself out of bed, much less work out.

SabrinaLC

I think WHAT you are eating is WAY more important than how much you are eating.
I honestly function best on 1000-1200 calories of fresh, whole foods.
I'm a small person, 4'11" and weigh just 104lbs. I am VERY sedentary about 80% of the day.

I'm not saying you're wrong, just throwing it out there that this is not going to be right for 100% of the people out there.

OkieTink

in...for the oncoming sh$t storm and show!

Ha. Me too.

Me three!

BluejayNY

I honestly never noticed a difference with losing weight with or without exercising. If I work out, then I naturally get hungrier and end up eating the calories I burned. I am not saying I am pro sitting on your butt starving yourself, but just that I haven't noticed a real difference.

That doesn't mean that's true for everyone, though. I didn't change my eating habits at all to lose weight. I just started exercising regularly again. I didn't count calories or log anything. Just got my lazy bum up and moved. I dropped 2 dress sizes (my goal) in 5 months.

No it isn't true for everyone, just like with your experience with adding exercise. I initially dropped 40 lbs just by eating smaller portions and making healthier choices and just doing a walk 5 days a week. It was almost entirely from changing my diet. I have maintained my weight whether I am working out hardcore or sitting on my butt which I have been doing for a year now. It seems my body is happy here so if I am more active it tells me to eat more so I don't drop anymore weight.

eric_sg61

Everyone's an expert.

Including you right?

bcattoes

I honestly never noticed a difference with losing weight with or without exercising. If I work out, then I naturally get hungrier and end up eating the calories I burned. I am not saying I am pro sitting on your butt starving yourself, but just that I haven't noticed a real difference.

That doesn't mean that's true for everyone, though. I didn't change my eating habits at all to lose weight. I just started exercising regularly again. I didn't count calories or log anything. Just got my lazy bum up and moved. I dropped 2 dress sizes (my goal) in 5 months.

No it isn't true for everyone, just like with your experience with adding exercise. I initially dropped 40 lbs just by eating smaller portions and making healthier choices and just doing a walk 5 days a week. It was almost entirely from changing my diet. I have maintained my weight whether I am working out hardcore or sitting on my butt which I have been doing for a year now. It seems my body is happy here so if I am more active it tells me to eat more so I don't drop anymore weight.

You do need to eat more to maintain if you exercise because your TDEE will be higher. You were just eating too much more if you gained.

I had the opposite problem. I stopped exercising, thereby lowering my TDEE, but kept eating the same amount as with exercise. I could have lowered calories (I was already eating healthy foods, just too much of them) but I really like to eat, and drink.

xinit0

-How can I gain muscle but make sure I don't put any fat on?

1) Impossible. If you are gaining weight, you are gaining fat. You can make sure you are gaining as much muscle as possible in relation to fat by gaining slowly and weightlifting.

Um... what?

DatMurse

One thing that stands out from the first study is the average 454 calories decrease in the TDEE of people in -25% caloric restriction group after 3 months. This means that the slowed metabolism would fully counteract the -25% caloric deficit if your starting TDEE is less than 1816, resulting in the dreaded plateau.

Let's say a sedentary person's TDEE is 2000 calories. A 25% caloric reduction would put him on a 1500 calories diet. If that 25% reduction ends up slowing his metabolism to 1546, he only has effectively 54 calories of deficit, which is barely perceptible and can easily be negated by miscounting a couple of tablespoons of sugar.

The most important point is that you can combat slow metabolism through exercise.

But your hypothetical people likely do not need to lose weight. I used my height (69.5") and age (54) and selected sedentary on a TDEE calculator and got 1968 when I set the weight for a BMI of 25 (171). When I set it to my old weight of 225, it went up to 2371. Throw in moderate exercise and it goes over 3000. Older and/or shorter people can have the lower TDEE numbers but again, if you add in extra pounds, the numbers go up. I don't think the study validates the idea of plateaus at all.

I agree about the exercise, but I am not sure whether that study proves it or not.

I'm 5'8" and my sedentary TDEE for my starting weight of 175lbs is a little above 2100. Shorter people can easily have 1800 TDEE or less and be overweight.

The study shows that the group that did both calorie restriction and exercise did not see any reduction in their TDEE.

I seen alot of your posts and none of them make any sense.

This one doesnt either

lunahbby

My BMR - using a calculator that ACTUALLY takes into account my 40% BF and DOESN'T assume that at 170 lbs, I am at a good balance of BF and LBM for my height - is about 1370. In a sedentary lifestyle, my TDEE is 1644. Not everyone is running 2000+ TDEEs, and not everyone is eating "extremely low calorie" at 1200 or less. Just throwing that out there. For some of us sedentary, short women, 1200 calories or less is actually necessary to lose any sort of proper weight

55in13

Another thought about exercise...

My understanding about reduced metabolism is that it is achieved by the body doing less work (lower HR and respiration, slower peristalsis, less hormone production, etc) not by doing work more efficiently. Running (my primary exercise) is pretty much always measured by units of work - moving mass over distance. So my belief is that lowered metabolism does not decrease the extra deficit caused by exercise.

Hexahedra

One thing that stands out from the first study is the average 454 calories decrease in the TDEE of people in -25% caloric restriction group after 3 months. This means that the slowed metabolism would fully counteract the -25% caloric deficit if your starting TDEE is less than 1816, resulting in the dreaded plateau.

Let's say a sedentary person's TDEE is 2000 calories. A 25% caloric reduction would put him on a 1500 calories diet. If that 25% reduction ends up slowing his metabolism to 1546, he only has effectively 54 calories of deficit, which is barely perceptible and can easily be negated by miscounting a couple of tablespoons of sugar.

The most important point is that you can combat slow metabolism through exercise.

But your hypothetical people likely do not need to lose weight. I used my height (69.5") and age (54) and selected sedentary on a TDEE calculator and got 1968 when I set the weight for a BMI of 25 (171). When I set it to my old weight of 225, it went up to 2371. Throw in moderate exercise and it goes over 3000. Older and/or shorter people can have the lower TDEE numbers but again, if you add in extra pounds, the numbers go up. I don't think the study validates the idea of plateaus at all.

I agree about the exercise, but I am not sure whether that study proves it or not.

I'm 5'8" and my sedentary TDEE for my starting weight of 175lbs is a little above 2100. Shorter people can easily have 1800 TDEE or less and be overweight.

The study shows that the group that did both calorie restriction and exercise did not see any reduction in their TDEE.

I seen alot of your posts and none of them make any sense.

This one doesnt either

Then unless you're willing to point out where I'm wrong, I say you need to read better.

watcheronthewall

You can say what you want but I have been surviving on a 1200 calorie diet, as recommended by my dietician, since December. It is the first time I have been successful at losing weight. I have tried dieting with higher calories allotments and with as much exercise as I am doing now...but with no results. ABSOLUTELY NONE. As I said, this is the FIRST TIME that I have been successful at losing weight in a very long time.

I also know that, as I continue on this journey of mine, my exercise is increasing not decreasing. I am moving more than ever, and loving it.

I believe everyone is different and there is no exact science to weight loss. My diet is working, better than I ever hoped it would, and I am sticking with it. It is balanced, thus providing me with all of the nutrients I need, and I can do this. No charts and graphs are going to change my mind. Thanks for trying, though.

I would be really careful with such a restrictive calorie goal. In the long term there is a very real possibility of 'falling off the wagon' and ending up binging because you are restricting your calorie intake so much. You shouldn't take these things personally, it is very possible that you have done well on 1200 but that doesn't mean it will always work. Realistically, existing on a higher calorie goal is much more sustainable and lessons the chance of going back to old habits or encountering problems.