can restricting calories too low mess your matabolism in the future?

trulyhealy

i was watching videos on how to build muscle and lose fat and a girl said that if you eat too low it can mess you up the future in terms of not losing any weight.

how do you avoid this not eating enough or eating too much. for example i eat 1,300 calores a day roughly and idk if that’s really unhealthy?? i mean i’ve done that and lost a pound a week so idk if it’s too low and then on another calculator it said to eat 1,500 but i feel like that’s too much to lose a pound a week.

tbh this makes no sense and idk where the question is in this i’m just stressed and if anyone knows anything about this and wants to share some know that would be good bc i don’t really know a lot.

i’m 20
5 foot 5
157 pounds

and my plans are to lose weight on 1,300 roughly until i lose like 17-20 and then raise the the calories up and weight train so i can gain muscle. but i’m weight training now but idk if it’s doing anything bc i’m not eating at a surplus

psuLemon

Without seeing the reference, i would suggest its bit of an exaggeration, but if you eat severely low calories, it can lead to muscle loss, nutrient deficiencies or general lethargy. This would reduce your daily calorie output (TDEE). This could also lead to binging issues. I have generally seen this in people who are eating super low calorie.

kimny72

Hun, you really need to stop watching these YT videos. They just give you unnecessary stuff to worry about.

Set your goal to lose no more than 1 lb per week. Eat all the calories mfp gives you, plus some exercise calories. Eat a balanced and varied diet. Fit in some treats. Move more. Take good care of yourself.

NovusDies

You do not need to guess or fret. Just follow @kimny72's advice and as long as you do not feel fatigued stick with it for 6 weeks. Try to be consistent with the percentage of exercise calories you decide to eat. When that time period is up you calculate the total amount you have lost and divide it by 6. If you are losing more than about 1.25 pounds per week you need to eat more. If you are losing less than .75 pounds per week you have the option to eat a little less if you feel it is sustainable. If you need help figuring out how to adjust it come back and ask for help.

PAV8888

trulyhealy wrote: »

and my plans are to lose weight on 1,300 roughly until i lose like 17-20 and then raise the the calories up and weight train so i can gain muscle. but i’m weight training now but idk if it’s doing anything bc i’m not eating at a surplus

You training now is excellent and helpful regardless of your current weight and future plans.

Are you planning to compete in bodybuilding or similar shows? Is there any reason you are already planning to decrease and increase your weight?

By far, I would suggest, your best chance to lose some excess fat that you may have and not end up with it on you again involves losing weight relatively slowly doing things and eating in ways you can continue to do so long term and while continuing to eat as many calories as possibly subject to you meeting your goals.

People lose weight and regain all the time in spite of not having this as their goal because our bodies are remarkable at wanting to maintain energy reserves while food and drink is plentiful, tasty, and relatively inexpensive and easy to access while our required caloric expenditure in an online world is relatively low.

I see no reason to be setting out to regain weight unless this is under very specific circumstances.

kshama2001

kimny72 wrote: »

Hun, you really need to stop watching these YT videos. They just give you unnecessary stuff to worry about.

Set your goal to lose no more than 1 lb per week. Eat all the calories mfp gives you, plus some exercise calories. Eat a balanced and varied diet. Fit in some treats. Move more. Take good care of yourself.

Yes, @trulyhealy no need to over-complicate things. The other calculator may have used a different methodology. Just use MFP as it was designed.

CSARdiver

Objectively - no. At least not long term.

There are a few small population studies that suggest a shift in metabolism when losing a great deal of weight in a shorter period of time in comparison to predictions. Note there are currently no directed studies proving this and the existing studies rely on self reporting.

Metabolism is a series of biochemical reactions which are very stable and contain little variation. Even the variation we believe occurring likely is not as great as we currently believe - largely due to the lack of precision and accuracy in detection equipment.

I recommend beginning some form of progressive resistance program now though. No real reason to wait on this and this will aid in preserving muscle tissue in a caloric deficit.

What you're describing is the typical cutting/bulking cycle. Sound strategy, but has little to no impact on your metabolism.

psychod787

CSARdiver wrote: »

Objectively - no. At least not long term.

There are a few small population studies that suggest a shift in metabolism when losing a great deal of weight in a shorter period of time in comparison to predictions. Note there are currently no directed studies proving this and the existing studies rely on self reporting.

Metabolism is a series of biochemical reactions which are very stable and contain little variation. Even the variation we believe occurring likely is not as great as we currently believe - largely due to the lack of precision and accuracy in detection equipment.

I recommend beginning some form of progressive resistance program now though. No real reason to wait on this and this will aid in preserving muscle tissue in a caloric deficit.

What you're describing is the typical cutting/bulking cycle. Sound strategy, but has little to no impact on your metabolism.

Agreed with this. Though OP, from my reading AT is small at best over what would be predicted. What I do not think is in doubt, is most of the reduced energy expenditure during and post weight loss comes from a decrease in NEAT and and increase in skeletal muscle fuel efficiency. Basically you move less and muscle becomes better at burning energy per contractile use. If you want to play your angles... get a fitbit or similar device to monitor NEAT. Start a progressive overload resistance training routine several days a week. There is some evidence that resistance training helps reduce skeletal muscle efficiency post weight loss. Increase your protein to about 1.6g/kg. Some evidence that it helps reduce some of the TDEE decreases during and post weight loss. Good luck. If you need references, feel free to ask.

magnusthenerd

To date, any of the models I've seen used to claim individuals have had permanent adaptive thermogenesis resulting in a lower BMR than others at the same weight have been questionable.
I believe Menno Henselmans has a paper out somewhere with a model that says there is no permanent adaptive thermogenesis once changes in body tissue composition is are accurately accounted for. If Menno is right, it would mean all one should worry about is preserving lean tissue. So lift weights...
Anecdotally, I think a number of people on MFP who have lost weight tend to track out or get body calorimetry done that shows their calorie burn is above expected for their weight, which I take to be from these people doing resistance training and having a higher lean mass than most people their same weight.

psychod787

magnusthenerd wrote: »

To date, any of the models I've seen used to claim individuals have had permanent adaptive thermogenesis resulting in a lower BMR than others at the same weight have been questionable.
I believe Menno Henselmans has a paper out somewhere with a model that says there is no permanent adaptive thermogenesis once changes in body tissue composition is are accurately accounted for. If Menno is right, it would mean all one should worry about is preserving lean tissue. So lift weights...
Anecdotally, I think a number of people on MFP who have lost weight tend to track out or get body calorimetry done that shows their calorie burn is above expected for their weight, which I take to be from these people doing resistance training and having a higher lean mass than most people their same weight.

While I agree, if there is any long term AT to rmr it is minimal at best. The biggest issue is NEAT and muscle efficiency. Unfortunately, long term data is lacking in how long these might persist. Though n=1, the leaner I became the more I moved. Just spontaneously. Now, its hard to keep me sitting still, so, who knows?