Am I ruining my metabolism?

I would say you should consume at least 1200 calories a day, to avoid the dreaded starvation mode. Loosing more than 3-4 lbs a week can be very unhealthy, and can lead to many problems down the road, like loose skin for example. At first you will probably lose quite a bit, but it will, most likely, slow down. When this occurs, just change up your workout routine and keep your body guessin'.

I would say you should consume at least 1200 calories a day, to avoid the dreaded starvation mode. Loosing more than 3-4 lbs a week can be very unhealthy, and can lead to many problems down the road, like loose skin for example. At first you will probably lose quite a bit, but it will, most likely, slow down. When this occurs, just change up your workout routine and keep your body guessin'.

Agree!

1200 is the healthy minimum. I don't think you can ruin your metabolism in 3 or 4 days but this isn't a good long term strategy. Remember you didn't just wake up this weight. It took time to put it on it's gonna take time to get it off. Do you exercise? That will burn calories and increase your metabolism. 1900 is a good number you don't have to restrict yourself so much you have a better chance at making a lifestyle change apposed to just being on a diet. Because when your on a diet you eventually get off the diet and end up right back where you started.

P. S. Are you sure it says 5 months and not 5 weeks?

Eat the 1900.

1200 is acceptable for a woman, but according to your profile, you're 18 years old and male-- and 6'3"! You need a lot more calories than the ladies need. You may find you need even more than 1900 to be honest... if you find yourself losing very slowly or getting headaches/dizziness, you should check your BMR using the calculator on the tools tab. Your BMR is often higher than the calories MFP gives, and sometimes you need to eat a little more in order to feel healthy.

Hello, My name is Mason. I am about 6'3" and 270lbs. I started 3 or 4 days ago, and it hasn't been very difficult so far. I'm actually saving myself about 700 calories a day. Myfitnesspal gave me a goal of 1900 calories a day. And I have been eating around 1100. I am wondering if this hurts my metabolism, and will hurt me in the long run. It tells me that at 1900 calories a day, I will be 254 in 5 months, but I assume that if I don't eat all 1900, I will lose weight faster. Should I eat 1900 or keep doing what I'm doing?

Ruining your metabolism? No, you're putting a gun to its head and slowly squeezing the trigger...

I read that you are 18. Based on your height and assuming you are not doing ANY exercise per week your maintenance level of calories will be about 2800. If you are doing some sort of exercise it will be higher, well into 3000.

1100 calories per day is way, way too low. Luckily you haven't been doing it for long enough to do any damage.

I think 1900 is even too low straight off the bat but it is something you can work up to once your weight is lower. Try 2300 and cut your calories by 150 every two weeks until you get to a steady rate of loss of 2lbs a week. I f you are exercising remember to account for that and eat back those calories.

Also, start lifting weights to preserve muscle.

Good luck.

Let me come down in the middle here. At your level of starting weight, a 1000 cal deficit a day, or *maybe*even* a *little* more could be sustainable. If 1900 is what you get for a 1 lb / week loss (500 cal/day deficit) then I'd say you're ok to go for 1400 to accelerate. Once you get closer to your goal weight, you'll have to reduce the deficit, and loss will be slower, but yes, very overweight people CAN, for a while, loose quite quickly while eating comfortably enough.

However, there is a level of deficit where your metabolism will slow down to the point that you're better off eating slightly more but keeping the engines fired up. Exercise will help (eat back a few of those extra calories, but be conservative estimating). Also, note that too big a deficit will increase loss of muscle mass, which you want to avoid.

When I was doing the Curves diet they recommended 1200 CALS FOR 1 WEEK followed by 2 weeks at 1600 cals then 1 week at 2400 cals which is coincidently very close to my recommended cals and bms. But they stressed that this was for women NOT men. Men should consume more calories.

Putting this in perspective if you take your recommended daily calories and multiplied by 75%(this would be 1425 in your case) this would be what you should eat for one week then your recommended cals for week 2 and 3 and then your BMS for the last week.

BUT you also have to factor in your lifestyle as a teenager. Most teens are more active than they realize. Whether it's walking to school, between classes up and down stairs, sports, PE class, walking the mall, whatever.... that activity will factor into your recommended target as well.

What it all comes down to is the quality of what you eat not the quantity. Healthy proteins, fruits and veggies, whole grains.... and staying active.

Set goals that don't center around food. For exampke set a goal of walking a 5k this summer or a turkey trot on Thanksgiving. The more tangible it is the easier it will be to stay focussed.

This is a fantastic thread. Just reading everyones opinions is so helpful.

Thanks all.

Hey man, I started here at 6'5 @ 270, and at 2000. Now I'm 6'5 @ 240, eating 2400 still at a deficit. Don't cut too much too fast, because once you stall at such a low deficit, where do you go from there?