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Do anorexics and underweight people eat less calories than they burn?

As I heard that to gain weight you eat more calories than you burn so I assumed the opposite is true to lose weight?
Reply 1
Yes but anorexia is an eating disorder where people form unhealthy habits around eating such few calories. I can't do the topic any justice so won't try.
Reply 2
i think it's mostly genetics. i've always been underweight, even despite eating lots of chocolate as a kid
Not all people who are underweight have anorexia. Not all people with anorexia are underweight. Both can be very serious.

But to answer your question:
Original post by Anony345533
As I heard that to gain weight you eat more calories than you burn so I assumed the opposite is true to lose weight?

Essentially:
energy in = energy out ––> maintain weight
energy in < energy out ––> lose weight
energy in > energy out ––> gain weight
Original post by Ciel.
i think it's mostly genetics. i've always been underweight, even despite eating lots of chocolate as a kid


This is not how genetics work
Original post by Anony345533
As I heard that to gain weight you eat more calories than you burn so I assumed the opposite is true to lose weight?


No underweight people who maintain a steady weight, are eating the same calories as they burn.

If they are losing weight they are burning more than they are eating
Reply 6
Original post by Anony345533
As I heard that to gain weight you eat more calories than you burn so I assumed the opposite is true to lose weight?

Anorexic and underweight people might not be eating less calories than they burn. They could be eating as much as they burn, but too little for their body's daily requirement. For every height-weight range, there is a certain amount you should eat everyday to be healthy like putting fuel in a car. Anorexics and underweight people usually eat less than this recommended amount.

However, I think underweight people with a high metabolism are the exception to this rule. They could be eating a lot more than most with no exercise yet they won't put on weight. My current flatmate is a lot smaller than I yet she eats thrice what I eat. Even on days I eat more for working out, she eats double that. That's just her physique.
Reply 7
Original post by Angry cucumber
This is not how genetics work


genetics are partially responsible for your weight. but you can deny it all you want.
Original post by Ciel.
genetics are partially responsible for your weight. but you can deny it all you want.



You didn't say that
Reply 9
Original post by Angry cucumber
You didn't say that


i said mostly but that was when i was referring to skinny people with high metabolism
most fat people do overeat
Reply 10
Original post by bl0bf1sh
Not all people who are underweight have anorexia. Not all people with anorexia are underweight. Both can be very serious.

But to answer your question:

Essentially:
energy in = energy out ––> maintain weight
energy in < energy out ––> lose weight
energy in > energy out ––> gain weight


"Not all people with anorexia are underweight" - maybe not on the BMI scale, but one of the diagnostic criteria is to have a lower bodyweight than is healthy for the individual.

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