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

deksgrl

In for "I can't possibly eat more than 1200 cals or I will pack on 5 pounds tomorrow".

_lyndseybrooke_

You're also above average in height for a female. There are a lot of women who are much smaller than you and don't have your caloric requirements. There's nothing magic about the number 1200.

That's my point. Women think, "oops, these pants are getting tight. I need to go on a diet," and they automatically go to 1200 calories per day with no good reason. I think I said in my original answer, "unless you're tiny..." because I know very small women will need less calories, but it's not only very small women limiting their caloric intake to 1200 daily.

With my stats...

BMR: 1500-1600 (depending on the formula)
TDEE (little to no exercise): 1920
TDEE (exercise 5 days/week): 2339

So, if I'm not laying in bed all day but I'm not actually exercising, I burn 300-400 calories just with my daily activities. So, a 500 calorie deficit would be 1420. Cutting more than 500 calories per day doesn't sound like a very healthy option. If I exercise 5 days per week, I could eat 1700 calories and still lose weight. If I eat less, I'll be working on a calorie deficit way less than TDEE-25%, which some people think is excessive. So, I'll admit that I probably don't eat enough (and I'm going up slowly), which is why eating 1200 calories seems that much worse.

kirstyfairhead

The information provided shows a number of things:

1. A calorie restriction plus exercise gives the best balance of fat/LBM loss
2. A low calorie diet achieves the greatest fat loss but with the down-side of increased LBM loss

Would love to see the same study with LCD plus exercise, then we would have a complete picture.

Unfortunately this study still says that if you want to lose the most fat and the most weight a LCD is the way to go, you will lose LBM as well but depending on where you are depends on your priorities.

A person who is significantly overweight may consider that a loss of LBM is a perfectly acceptable sacrifice in order to reduce weight and minimise the health risks that go with being that heavy. Can't say I would disagree with them.

They are also perfectly capable of slowly increasing calories and moving towards a sustainable food intake as they get closer to their goal.

Lots of people fall off the wagon on a LCD because it's too restrictive, lots of people fall of the wagon exercising (including lifting) because it takes up too much time etc. Plenty of people would think that eating lots of protein to support lifting and looking ripped was just as unsustainable as a LCD and could argue that if you stop exercising when you are accustomed to eating that much food you are gonna get huge pretty quickly.

So YES 1200 cal diets are bad....for quite a lot of people, quite a lot of the time but with loads and loads of exceptions - Backed by Science

rosemaryhon

...Lots of people fall off the wagon on a LCD because it's too restrictive, lots of people fall of the wagon exercising (including lifting) because it takes up too much time etc. Plenty of people would think that eating lots of protein to support lifting and looking ripped was just as unsustainable as a LCD and could argue that if you stop exercising when you are accustomed to eating that much food you are gonna get huge pretty quickly....

I have wondered about this ^^ ~ seems to me could be a similar risk.

So YES 1200 cal diets are bad....for quite a lot of people, quite a lot of the time but with loads and loads of exceptions - Backed by Science

I agree.

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.

55in13

Disclaimer - I have lost almost 50 pounds in 6 months by eating mostly in the 1000-1500 range with occasional days of even less (a quirk of mine around the zeros; when I see a digit disappear from the tens' place, I don't ever want to see it again). During this period I did the C25K and now run 3 times a week. I have run over 40 miles so far this month and will probably run 6 or 8 more tonight. I also bike and hike with my kids, do yard work, etc. I am no lethargic lump. So my personal experience is at odds with the study.

There is a lot of conjecture about what happens when you go to maintenance. It may be that the metabolism recovers. I don't know whether it does or not; just pointing out that the conclusion of "this is bad" is partially based on conjecture.

I read one study that said that metabolism slowed between 4% and 10% when dieting. I don't remember what the parameters were as far as how fast the participants were losing weight. I do remember it was done on people using a diet service (like Weight Watchers, but I don't remember if that was the one). Anyway, the point of that study was that some drop seems inevitable.

Another line of thought to consider...
Are obese people more likely to get to a healthy weight using LCD than by taking more time using a diet with higher calories?
Are they more likely to regain the weight if they used LCD to lose it?
If data from the first two questions are taken together, which method results in more people getting to a healthy weight and staying there?

One last note - note that under study conditions, these people did lose the weight and while metabolism slowed it did not reach a level where weight loss stopped.

55in13

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.

arains89

This is not science I know but I have been netting 1200 cals for 5 months now. I eat back my exercise cals and exercise everyday. I lost well in the beginning but the last two months the only weeks I have seen a loss are the weeks where I have slipped up and gone over on cals or missed some workouts. From following this pattern I can only assume that (since I refuse to workout less) I need to be eating more (especially being only 18 pounds from goal weight). My TDEE at sendentary is 1850 - 20% is about 1450 cals per day so this is what I set my cal goal to and am planning to eat back most of my exercise cals as well. This still puts me at a fairly large deficit. I think that at least from personal experience 1200 cals worked at first but I think my body has outgrown it...

lanajaymurphy

Got to be in it to win it.

Vailara

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.

bcattoes

If you think 200 calories make a significant difference then carry on doing what you are doing.

EDIT

Have you not made goal in over a year?

If 200 calories makes no difference then 1400 is just as bad as 1200. And that would make 1600 just as bad as 1400, which is just as bad as 1200, which, apparently, is just as bad 1000.

If 200 calories makes no difference then someone with a TDEE of 1900 would lose nothing by eating 1700 (more than a 10% deficit), and would gain nothing by eating 2100.

Of course 200 makes a difference. Don't be ridiculous.

holliebevineau

I love MFP!!!!!

MaydayParadeGirl

Redacted.

Broscience: it's completely unquestionable and 100% reliable! XD

Its sod all to do with broscience. Its everything to do with actual science.

Read the study and understand.

The study doesn't really support what you claim.

The main thing to get from the results is that losing weight while exercising is way better than losing weight while not exercising.

Man I'm just reading everything you're posting in here and taking your advice At the moment I have a bad ankle which once my health insurance kicks in i'm getting looked at to get the okay to go forward and really exercise. So at this time I'm going with the 1200 calorie intake because I'm not that active. Like you said though, exercising is a way better way to lose weight and I'm going to up my calorie intake at that point. Hopefully when I get there and ask people for help they won't spew their judgment about the 1200 diet i was on and will actually offer help and intelligence. Thank you for being intelligent about it.

kitka82

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

Ha. Me too.

55in13

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

I don't think it explains most of them. I think we all know what causes about 90% of them, but it seems like the only subject that is taboo on MFP is honesty.

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.

mjharman

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.

There is an exact science to weight loss. you do not defy the laws of energy
well did you confirm not having hypothyroidism?
Did you weigh all your food out?
Did you have a diary?

Yes - I was referred to the dietician by my endocrinologist.
Yes - I weighed all of my food out...I was EXTREMELY exact.
Yes - I used MFP
BELIEVE ME, I was extremely exact and dedicated, which was why I was so upset when nothing worked. It is also why, when I left the dietician's office on December 27th, I was sure I could follow the diet she gave me but was also sure that it would not work. Imagine my surprise when it did!

I have to wonder if any of the subjects studied were 54 year old, post-menopausal, diabetic women. HMMMM....

And let me also mention that my MFP ticker does not indicate my actual weight loss. When I left the dietician's office that day, I weighed 256.4 pounds. Today I weigh 207.4. That's a 49 pound weight loss in less than 6 months...so I am definitely going to argue that the "methodology" that you are pushing is "exact science."

First of all, it's dietitian, not dietician.

Second of all, your diary is closed.

OK - so if you're going to start correcting my spelling, I'm thinking I may have hit a nerve. Second, my diary is closed because I am a private person and I prefer it that way.

I didn't mean to make y'all mad. What y'all are doing is working for you, and that is good. All I was pointing out was that we are all on a weight loss journey, and it is our own. A formula that works for the majority does not necessarily work for all, so stop assuming that it does. I have found what works for me, and honestly, I could eat like this for the rest of my life. It is not difficult for a 5'4" woman to eat this way. However, I am sure that when I reach my goal weight, my DIETITIAN will advise me on how to eat in order to maintain my weight loss. She is, after all, my personal medical authority.

If you are curious, here is my typical day:
Breakfast: 1 piece of wheat toast with a teaspoon of butter, a small banana, and a cup of coffee

Lunch: a salad consisting of mixed lettuce greens, red, yellow, and orange pepper strips, broccolli, and grilled chicken breast topped with fat free honey dijon dressing

-or-

a sandwich made with 2 pieces of whole wheat bread, mustard, Boar's Head chipotle chicken deli meat, lettuce leaves and tomato slices, a cup of red, yellow, and orange pepper strips, and a cup of fruit, such as watermelon or pineapple

Afternoon snack: a cup of Greek yogurt and a piece of fruit, such as an apple or peach

Dinner: Whatever I prepare for my husband and 3 adult sons, but in smaller portion sizes. I use a salad plate rather than a full-size one, and fill 1/2 with the vegetable of the day.
Last night's dinner was: 1 boneless, skinless chicken thigh cooked on the grill with 2 TBSP barbeque sauce, 1/2 cup of stuffing, and steamed spring vegetable mix

I also spent 2 hours at the gym yesterday, 1 in a Zumba class and 1 in a body pump class.

What is so difficult about that?

RGv2

You must have a calorie deficit to loose weight. Burning more than 3500 calories than you consume results in the loss of 1 pound. By reducing your calories/ day by 500 (from your maintenance calories/the calories your body burns without additional exercise) you will loose 1 pound a week. By only loosing 1 pound a week you also prevent your body from going catabolic and using your muscle as an energy source.

So, if my maintenance calories works out to be about 1850/day than I should be eating 1350 calories/day. Which I have been doing and which has helped me to loose 40 pounds. When I was swimming varsity I wasn't calorie counting and although I was swimming 2 hours every day plus lifting I was eating to my maintenance and therefore had no deficit.

Now if a body building male tried to eat 1200 calories it would be devastating and he would loose muscle mass because his maintenance calories are so high. The average woman however has a maintenance of about 1700 so therefore 1200 would be the perfect amount.

Source: Varsity swim team coaches, online research, personal experience dieting bodybuilding and varsity swimming.

I LOL'd at "Varsity swim team coaches", and "varsity swimming" as a source.

believe22

Everyone's an expert.

Eating 1200 cal/day is so bad, I lost 80 lbs and have kept it off a year and a half. Its awful, don't do it!

anazombee

:huh: