I weigh 340lbs and recently started a diet, but I'm worried I'm not eating enough.

[the13th]

(I am male) I started this diet on the 11th of this month, for the first few days I limited myself to 1200 per day, eating lots of fruits and vegetables and lean protein. I bumped it up to 1500 after someone told me that I might slow my metabolism to a halt. My BMR is just under 3000 so I figured I was burning near a half a pound of body fat per day. I realize it can't be that easy, I must be doing something wrong. This diet is going great so far, but I don't want to gain weight because I am limiting myself too much. I haven't started exercising yet, but I have some basic cardio and strength building routines planned.

I need to know the lowest numbers of calories I can eat per day and the minimal amount of exercise I must do so that I don't gain weight or lose all my muscle mass.

 

[summer123]

Your hoping to lose 0.5lb per day?! You realise that wont all be coming from body fat?

Your body cannot metabolise more then 2lbs of body fat PER WEEK, more then this and you lose it through muscle, glycogen and even bone mass. None of which you really want to lose from (I hope) if your body feels you are at risk of losing too much weight or losing weight too fast, it will slow itself down, try hard to conserve calories and favor utilising calories from muscle rather then that from fat.

Go back to your BMR, I'd make a cut of 25% max at first, see how it goes for a 2 week period before thinking about cutting again.

Eat a healthy and balanced diet: 2grams of protein per 1kg of your body weight. (Tuna strak of 125g would have about 35grams of protein in for an example) you will need to look at nutritional guidelines and weigh stuff before you memorise everything and trust yourself more but even then, take 1 day a week to weigh what you eat for that day to make sure you don't go off the rails!

Its important to get the macros and nutrients right though (eg protein, vitamins, minerals etc) as these not only help your body to work properly but they also help prevent cravings! If your body lacks certain nutrients for example you will often find yourself with strong cravings for foods rich in those nutrients which is the last thing you need when trying to be strict about what you eat!

 

[biggestloser105]

(I am male) I started this diet on the 11th of this month, for the first few days I limited myself to 1200 per day, eating lots of fruits and vegetables and lean protein. I bumped it up to 1500 after someone told me that I might slow my metabolism to a halt. My BMR is just under 3000 so I figured I was burning near a half a pound of body fat per day. I realize it can't be that easy, I must be doing something wrong. This diet is going great so far, but I don't want to gain weight because I am limiting myself too much. I haven't started exercising yet, but I have some basic cardio and strength building routines planned.

I need to know the lowest numbers of calories I can eat per day and the minimal amount of exercise I must do so that I don't gain weight or lose all my muscle mass.

You're not going to gain weight from eating too little, if you eat too little your metabolism will slow down, but you'll keep losing weight (just not as quickly or healthily as you could be). The main problem with being in starvation mode isn't so much the sub-optimal weight loss, but the negative health effects you'll suffer from your body not having enough nutrients. You could even get mental health issues because your brain won't have the resources to make the neurotransmitters.

Because you weigh 340, losing muscle mass will not be a huge concern for you provided you do resistance exercises. Muscle loss is a much more serious issue for someone who is already close to their goal weight, with a lot of fat, oversized organs, excess skin, tendons and all that your body has plenty of resources (fat and lean) to draw on. You'll want to lose some lean mass when your organs adjust to a healthier size for example.

Usually, starvation mode is a concern when you drastically cut calories (like by 50% of your BMR). 1200 calorie is something a woman could eat, but a man your size should eat more.

I would aim to lose 2lbs per week initially, because you want to avoid loose skin and negative health effects. So eat 1000 calories less every day than you use. Since your BMR is ~3000, I would eat ~2000 calories.

You could lose weight faster than that, but then your risk of loose skin increases. I personally was initially losing weight faster than 2lbs per week, but now I have slowed it down to 2 lbs per week because I am noticing that my stomach is kind of saggy and I really don't want to deal with loose skin after I finish my weight loss.

 

[ocd]

Take it from me, if you do this you will be sorry.

I did this. You will think you are making amazing progress up until you run out of muscle for your body to consume and get slapped in the face by a brick wall of reality.

It will feel great up until you hit that wall then you will be bagged all the time for energy and wonder why you are getting less fit instead of more fit as you get lighter.

You will dehydrate yourself and strip your body of lean muscle mass leaving you with a false sense of what you really weigh.

I was your exact weight when I started 340 pounds. I lost 180 pounds in 12 months, I got down as low as what I thought was 155 pounds but you know what? I looked terrible, flabby in the mid section and skeletal in the upper body, very frail and weak and cold all the time as well. I've since learned that I was probably dehydrated as hell too from going way too low in calories for so long so the weight I thought I was wasn't even real, I was just extra low on glycogen and body fluids. If you think you are going to shed that weight at that rate and come out looking like Ryan Reynolds in 12 months I have bad news...

There are no shortcuts. Take your time, do resistance training, lose maximum 2 pounds per week, and really 2 pounds per week is even pushing it for losing a lot of muscle mass. I did it the wrong way and now It's going to take me another year to put muscle back on again, like I say, there are no shortcuts. I wanted fast fast fast just like you do and didn't listen, but trust me it can be a bag of hurt.

I also developed an eating disorder bordering on bulimic behavior that I am still recovering from because of this behavior. The rapid swings in weight due to water weight loss and dehydrating myself, combined with weighing myself every day led to me becoming absolutely phobic of any weight gain. This is not healthy mentally or physically take my word on that. Really amazingly disturbing things start to happen to your mind when you lowball your calories that hard for too long. All the positivity, self esteem, and insight I had gained while losing weight got replaced by doubt depression and feelings of complete madness once I threw myself into a binge and restriction cycle. Every three to four days I would get cravings so hard I would literally feel as though I was going crazy. It got so bad at the worst of it that I started freaking out, panicking, screaming and yelling, feeling suicidal because I thought I was losing everything I worked for and the harder I tried to hold onto it by lowballing my calories the worse it got.

Yes I am making progress in reversing that now thanks to an article I found by a personal trainer, and the very generous support of that same trainer who I emailed to thank for having wrote the article that helped me start turning it around again.

I have a philosophy that staying overweight is about lying to yourself, at least it was for me. Take care however, that in your weight loss journey you don't start lying to yourself in a different way again. I did this by believing I could bang off 20 pounds a month and everything was going to be flawless when I hit 180. 180 came and went, 160 came and went, and the flab and loose skin remained. Granted I am still far better off than being morbidly obese, but in hindsight I really wish I had listened, you will too if you don't.

(EDIT) As I read over this I realize I make it sound pretty grave and dramatic, and I also realize that I am an obsessive compulsive person, (It's why I chose the forum name OCD afterall.) So your results may vary compared to mine. I concede that many people may have lost weight this fast and not ended up with a situation like mine, my own situation being clearly exacerbated by my own compulsive nature at every turn, still... save yourself future trouble and do it right.

 

[summer123]

(EDIT) As I read over this I realize I make it sound pretty grave and dramatic, and I also realize that I am an obsessive compulsive person, (It's why I chose the forum name OCD afterall.) So your results may vary compared to mine. I concede that many people may have lost weight this fast and not ended up with a situation like mine, my own situation being clearly exacerbated by my own compulsive nature at every turn, still... save yourself future trouble and do it right.

You didn't make it sound dramatic- this is what can so easily happen, the key thing is wanting to lose weight enough to allow it to happen.

You may be aware of the 1950s starvation trials they did with men who didn't want to fight in the war as they wanted to see the effects of starvation (they agreed to do this they weren't forced!) many developed the same issues, bulimia, obsessive thinking. I am not saying your personality traits are a result of what you did but for many it can infact breed and enhance these traits.

What you said was fine and was spot on and sadly very common.

 

[ocd]

You didn't make it sound dramatic- this is what can so easily happen, the key thing is wanting to lose weight enough to allow it to happen.

You may be aware of the 1950s starvation trials they did with men who didn't want to fight in the war as they wanted to see the effects of starvation (they agreed to do this they weren't forced!) many developed the same issues, bulimia, obsessive thinking. I am not saying your personality traits are a result of what you did but for many it can infact breed and enhance these traits.

What you said was fine and was spot on and sadly very common.

After my little experience in the effects of it it all makes perfect sense. The body's response is to make you meaner, less inhibited, willing to do whatever it takes to survive. I can understand how people facing true starvation in some situations have turned to cannibalism in reaction to those kinds of hormonal responses.

I had no idea how unbelievably and incredibly powerful their effects are on the mind. I literally was a Jekyll and Hyde personality when I would get into the extreme cravings like that. I was told as much by people in my private life who were in disbelief to see someone go from positive and outgoing at ten in the morning, to clawing your own eyes out despair and lashing out anger by evening, only to normalize again by the next morning after the binge for another three days for the cycle to repeat.

 

[summer123]

After my little experience in the effects of it it all makes perfect sense. The body's response is to make you meaner, less inhibited, willing to do whatever it takes to survive. I can understand how people facing true starvation in some situations have turned to cannibalism in reaction to those kinds of hormonal responses.

I had no idea how unbelievably and incredibly powerful their effects are on the mind. I literally was a Jekyll and Hyde personality when I would get into the extreme cravings like that. I was told as much by people in my private life who were in disbelief to see someone go from positive and outgoing at ten in the morning, to clawing your own eyes out despair and lashing out anger by evening, only to normalize again by the next morning after the binge for another three days for the cycle to repeat.

All very normal in the situation you were in:
Minnesota Starvation Experiment - Wikipedia, the free encyclopedia