Calorie deficit confusion

cxeex
cxeex Posts: 121 Member
in Health and Weight Loss
I’m not sure I’ve been doing this right.
I used an app which based on my weight etc to lose weight I should be eating 1300 calories a day. I’ve been leaving at least 500 each day on this but not sure I’m eating enough. Should I be eating the full 1300?

Replies

  • spiriteagle99
    spiriteagle99 Posts: 3,749 Member
    At least that much. How much weight are you hoping to lose? What are your current stats? To lose one pound a week, you would aim at 500 or so calories less than the calories you need to maintain your current weight. Are you using the MFP app? If so, enter your stats and your goal, then eat what it gives you, plus some or all of your exercise calories. It is not good to eat less than 1200 net calories if you are female as you can't get enough nutrition and you will probably lose muscle.
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    edited June 2021
    cxeex wrote: »
    I’m not sure I’ve been doing this right.
    I used an app which based on my weight etc to lose weight I should be eating 1300 calories a day. I’ve been leaving at least 500 each day on this but not sure I’m eating enough. Should I be eating the full 1300?

    Yeah...the 1300 is your deficit. Whatever calculator you used computed your maintenance calories and cut from that giving you 1300 calories. You don't take a deficit from your deficit...you would be vastly undereating. The calculator calculated your calorie target based on your stats and rate of loss goal.
  • yirara
    yirara Posts: 9,986 Member
    cxeex wrote: »
    I’m not sure I’ve been doing this right.
    I used an app which based on my weight etc to lose weight I should be eating 1300 calories a day. I’ve been leaving at least 500 each day on this but not sure I’m eating enough. Should I be eating the full 1300?

    Yes, you should be. Just eating 800 calories per day is ridiculously little and even dangerous. Even small children need more food than that.
  • KevHex
    KevHex Posts: 256 Member
    Make sure to eat back a portion of exercise calories as well if you are active.
  • age_is_just_a_number
    age_is_just_a_number Posts: 631 Member
    Yes, eat the 1300 calories.
    Plus: if you are adding extra calorie burn with exercise, then eat those calories as well.
    Sometimes I only ‘eat back’ half of my exercise calories. But invariably, I find this isn’t sufficient.
  • anativeapache
    anativeapache Posts: 1 Member
    GlenG1969 when you eat back your calories burned in exercise, do you still lose weight? I’m struggling with wrapping my brain around eating more and not less.
  • yirara
    yirara Posts: 9,986 Member
    anativeapache wrote: »
    GlenG1969 when you eat back your calories burned in exercise, do you still lose weight? I’m struggling with wrapping my brain around eating more and not less.

    Well, it's quite easy really.
    Imagine your calorie allowance per day is 1300 calories.
    Now you exercise for 300 calories.
    Burning calories is difficult for your body, and basically requires energy. Thus if you only ate 1300 calories and exercise for 300, then you've effectively only eaten 1300-300=1000 calories.
    Just eating 1000 calories is NOT sufficient.
  • yirara
    yirara Posts: 9,986 Member
    Hey, I currently eat about 1400 calories. When I go on one of my longer bike rides I burn about 800 calories.
    Imagine you do this every day. 1400-800 = 600 calories. How long could you live on 600 calories daily? When would you start to binge, when would your body start complaining, when would you develop health problems?
  • justhost
    justhost Posts: 4 Member
    edited June 2021
    This is my favorite calorie calculator because it takes just about everything into account. It will rarely recommend anything lower than 1300 calories.
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    anativeapache wrote: »
    GlenG1969 when you eat back your calories burned in exercise, do you still lose weight? I’m struggling with wrapping my brain around eating more and not less.

    You're already eating less (in a deficit) when you're eating to your MFP calorie target. Your MFP calorie target assumes no exercise...that's why there's no mention of it in the activity level descriptors. It's a weight loss target without exercise.

    Moving requires energy...that's what a calorie is. When you move more your body requires more energy. When I car commutes 60 miles round trip per day vs going around the block to the grocery store a couple times per week, it's going to require more fuel...in this case...calories.

    When you exercise, you are moving more than what you told MFP in your activity level, so you get more calories. It's really just math. MFP will give me about 1900 calories to lose 1 Lb per week. MFP is estimating my NEAT (No Exercise) maintenance calories in this case to be 2400 calories per day. If I go for a ride or walk or whatever and burn 300 calories, my target increases to 2,200 calories but I still maintain a 500 calorie deficit because my maintenance number of calories would have also moved up by 300 calories to 2,700 calories. 2,700-2,200=500 calorie deficit still.

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