A Primer on Calories

There’s a lot of confusion out there, so in the name of clarity, I’ll give you the basics on calorie intake, as simply as possible. A calorie is a unit of energy. Your body uses energy to fuel your daily activity. If you take in more energy than your body uses, it stores the excess, usually as fat, but if you’re lifting heavy and using your muscles it can and will use that excess energy to build muscle too. That’s what we want.

If you’re at a healthy weight and your goal is body recomposition, you need to eat AT LEAST as many calories as your body burns, preferably a little bit more. Your body needs raw materials to build muscle, and if it’s using all the calories you eat to fuel your activity there will not be any left to build muscle with. If you’re undereating at a healthy weight, your body will do whatever it can to burn fewer calories, so will slow down your metabolic processes and start burning muscle for fuel, because muscle requires more calories to maintain than fat. If you’re undereating, that muscle is taking up energy (calories) that your body would rather use to fuel your heartbeat and brain activity.

If you’re obese or overweight, you need to burn more calories than you consume to lose weight. Not too many more, I generally recommend keeping a 500 calorie deficit to keep your metabolism healthy. Alternately, you can use a calorie calculator to figure out how many calories your body will need to maintain your goal weight (including your activity), and eat that many calories. Your body will take care of the rest (that’s how I did it). If you keep your deficit relatively small and lift weights and get regular exercise, your body will tag your muscles as ‘in use’ and preserve them, burning stored fat to make up the deficit in energy in vs energy out. If you’re sedentary, your body will burn lean mass as well as fat to make up for that deficit.

NONE of this means that diets that don’t require calorie counting don’t work. It just means that, for some people, those diets help them to naturally and instinctively consume the number of calories that will support their goals. Different people can experience this with different diets. Some people (like me) don’t ever experience it (or at least I haven’t yet, and I’ve tried all the diets) and need to be at least somewhat aware of our energy requirements. And we need to eat enough to fuel our activity and support our goals. Restricting calories below that level is counterproductive and will ultimately lead to failure. For most people, including women over about 100 pounds, that means eating at least 2000 calories a day, much more for most of us (I eat about 3000 most days). Even to lose weight, very few of us will need to drop below that, and if we do we are setting ourselves up for a damaged metabolism and fat storage.

Here are two calorie calculators that I find realistic and helpful, neither of them will give you an unsustainably low calorie target, in fact you will likely be surprised by just how much you need to eat to stay healthy and support your goals.

Calculator 1

Calculator 2

49 thoughts on “A Primer on Calories

  1. Pingback: Reference Page: Go Kaleo | Gregory Taper

  2. Pingback: Getting Rid of That Pesky 'Last Five Pounds' -- and How to Deal With 'Problem Areas' - Freshwadda Brooks | Coming Soon!

  3. Hi, thanks for the great article and your website which is amazing and a breath of fresh air! One question though, I tried both those calorie calculators and they each gave me a very different result (about 700 calories difference). Which one would you say is more accurate?

  4. Hi there!

    I’m so glad I found this!! I was wondering though, is there a specific nutrient ratio that you suggest using? like 40/40/20 or 40/30/30?

    • No, find what works for you. Mine tend to average out to 20% protein, 30% fat and 50% carbs, and I think most people will do best with adequate protein, but our bodies are all so unique, so i don’t prescribe ratios.

  5. Do you change your caloric intake based on the intensity of your workout on a given day? I’m training for a marathon and I’ve noticed that on my rest or cross-training days I tend to eat just as much (if not more!) than I do on my running days. I recently read an article where the person being interviewed stated that she ate fewer calories on days that she didn’t work out hard. I guess it makes sense, but I’ve noticed that intense workouts seem to initially curb my appetite a bit, and I am hungrier on my rest days. Admittedly since I started distance running about 3 years ago, I’ve gone from 108 to 115. At 5’4″ I recognize that 115 is a perfectly healthy weight and I’m not trying at all to lose what I have gained, but having been in the 150′s in my former, pre-exercise life, I am a little nervous that maybe I’m trending in the wrong direction and just want to make sure I’m fueling myself correctly as a long distance runner. Just for reference, I currently eat around 2000 calories on my training days, and probably 2200 – 2300 on my rest/cross training days.

  6. These calculators don’t take into account nursing a baby. What do you suggest? Adding 500 calories to the BMR?

  7. Ok I just stumbled across this post from someone who posted it in Matt Stone’s new forums on his website. I haven’t counted calories in years and hate doing so! I’ve also probably about 75 – 100 pounds overweight and have been for most of my life. My weight issues are complicated – running the gamut from emotional baggage to possible thyroid/adrenal issues. However in recent years as I’ve finally acknowledged my issues with ENOS (eating disorders not otherwise specified), I’ve come to realize that maybe I’m not eating enough. I’ve been a fairly “healthy eater” as my friends always say for years now, bordering on orthorexia, but always feeling shameful for every advocating my health tips to anyone considering I’m so overweight.

    So recently a dietician informed me that most people in ED recovery should be eating 2500 at minimum a day. It’s very hard for me to believe that by eating more I could actually heal my body and eventually loose weight. In fact last year, I ditched a lot of my diet dogma (was fairly paleo) – found Matt’s blog and started eating carbs and gained about 10-15 pounds and have had severe bloating for over a year now.

    I’m just trying to get help with the whole calorie thing. I clicked on both those calculators and the first one says I’m at 2140 for my BMR and I think like 3420 for my TEE. So if I want to start loosing weight, what do I need to shoot for Please claify. Also the second calculator listed my BMR at 2500. Can you help me out in all of this.

    I’m also trying to eat intuitively – only when I’m hungry and some days I’m just not that hungry and may not be getting even my minimum calories.

    Thank you for any help you can give!

    • Hi Christy. I’d start with something really simple, 2500 a day, and walking for 15 minutes. Give that a couple weeks and see what happens. I think if you’re consistent, you’ll be surprised at how sustainable it is. It won’t be fast, but I think you’re probably very familiar with what happens when you lose weight fast. :)

      Check out this post too.

      • Thanks for getting back to me. I’m realizing that unless I eat stuff like ice cream or high fatty foods, it’s hard for me to even get in 2500 a day. Like today, I had 2 eggs, ezekiel bread with lots of butter and jam, then chick fil a 8 piece nuggets with side salad and ranch and sweet tea and ice cream cone and I’m stuffed. It’s almost 5 and I’m not even hungry. I’ve still got a 1000 cals to go. And that’s an average day for me. Being 240 pounds with lots of natural muscle, I even wonder how I can live off that little, but I’m just not hungry. I felt bloated after breakfast and didn’t want to eat lunch but was meeting a friend so I did. Do I force myself to eat more? I feel like it’s triggering my ED even more. And only walking for 15 minutes each day seems like such little exercise. I try to go to this lake by my house at least 3 times a week – it’s a 2.5 mile easy to moderate walk/hike. Just trying to get out of my disordered mindset and the way that I try to always make things harder than they have to be. The eating that much seems hard and the walking that little seems too easy. Thoughts? Thank you!!!!

          • What would you say about what I mentioned about feeling like I can’t even eat 2500 calories a day because I seem soo full on what little I do eat. What might be the problem there? Any thoughts would be appreciated! Thank you!

  8. When you punch in your weight for the calculator is it your current weight or the weight you want to be?
    Also, thank you. I think you’ve saved my life

  9. can someone help me with this. I shot my metabolism eating what this calculator is TELLING me to eat (about 1500 cal/day – and it was not the fault of this – I had food allergies and just was not eating muh) I must be reading this wrong or something.. Have blood sugar issues and just feel like crap and have been WAY under weight for a long time til finally I ate whatever I wanted and GAINED way too much. I want to lose about 55lbs. and I want to maintain that. Up until a year ago I was skinny fat at 120 lbs but I am 5’9″ and I was so sick. I have adrenal fatigue so crazy working out does not work for me right now but I bought the 100 day thing you have and am starting it and now the weather is nicer so I will be walking everyday as well. HELP!

    • I’ve never known this calculator to give such a low number. Is that the smaller of the two numbers the calculator gives you?

      • yes it was. 2172 BMR and 3436 TEE the 3rd time I tried it. It was running slow before so maybe it messed up? So waht does this mean? LOL I am not sure exactly what the BMR and TEE mean for me. And I did day 3 today on the 100 days and my kids did it too! LOL they thought it was fun (5 and 1) they are so goofy but it was cute!

        • BMR (basal metabolic rate) is the amount of calories your body uses just maintaining life processes (digestion, brain function, heart beat, etc), and TEE (total energy expenditure) is your BMR plus your activity, so the* total* number of calories you burn.

          Most women’s BMR is somewhere between 1400 and 1800 or so, so the first number was probably right if it was your BMR. The third set of numbers sounds a little high so I think you may have overestimated your exercise that time.

          • well, no wonder I felt like crap at 1400 calories a day. So I should shoot for about 2100 and up my exercise?

  10. I, like most women, find my actual TEE a little terrifying. Because I make a point of standing all day long.. regardless of what I am doing, I stand.. my TEE is crazy high 3700ish. In addition to standing all day I workout 6 days a week. So, while my REE is only 1600, my TEE is off the charts. EEK!

    I have read what you state above about a gazillion times over the years, but for some reason it finally sunk in. I have been eating below maintenance for… years while maintaining all sorts of activity from distance running to heavy lifting to kickboxing and have never really made any significant progress. I just stay the same.. regardless of how cleanly I eat, whether or not I drink alcohol… whether I fast or eat breakfast, regardless if my biggest macro is fat or carbs… I just maintain. But now, after reading your explanation, I get it! In order to see any sort of re-comp I need to eat more to displace the fat. What the hell is wrong with me?! Not sure what took so long to make this make sense. Regardless, thank you for the inspiration.

  11. Pingback: Finding Your Ideal Weight | Go Kaleo

  12. I’m having serious issues with this calorie measuring BS. It is so conflicting!!!!!!

    The 2 calorie calculators on this page state I should be at like 2300 or more per day (5’2″; 34, female, 128lbs, reasonable to rigorous activity)

    but the one I’ve been looking at (here – http://caloriecount.about.com/cc/calories-burned.php) tells me I am needing to not go above 1900 – and definitely NOT above 2100 even if I do tonnes of exercise.

    I’m sure it doesnt make that big a difference though, a 400 calorie or so divergence – what’s that, 4 apples? Anyway I eat anywhere from 1400 to 3000 calories a day (very weird I know) & I am at the pt of wanting to LEAN UP & REDEFINE, am looking to lose the tyre around the middle and overall be BADASS!!! Thanks for you cool site!

    • The calculators I linked here are more accurate than the one on caloriecount and other calorie tracking sites. Those sites are great for tracking, but they tend to give low-ball calorie targets, so err on the side of the calculators here, they take more factors into account. Hope that helps!

      • yay!!!!!! more food !!!!! :D :D :D I will strive to normalize at c. 2400 then and hopefully get off the merry go round, amusing though it is


  13. LOVE the link to the first calculator–thanks! And not to be an idiot, but if my BMR is 1,743 kcals and my TEE is 5,129 kcals then I am supposed to eat 500 kcals less than my BMR (1,243 kcals) in order to lose weight? Please advise…I miss my brain :)

    • Never eat less than your BMR. To lose weight, you want to eat a little less than your TEE. However, 5129 is REALLY high, and I suspect that unless you’re training hard for several hours a day you probably aren’t burning that much. Are you training hard for several hours a day? :)

      • I was CrossFitting 6 days a week but since I wasn’t losing weight I thought I’d cut back to 3 days a week in case my body was revolting and just needed a break. I am trying to find the “sweet spot” for food and exercise and am trying to determine what is too much/not enough for each. I am pretty heavy for my height at the moment but am also pretty strong so I imagine there is muscle under there somewhere that’s doing me some good. I did have my RMR done at my CF box at the end of the summer doing one of those breathing tests and the trainer was surprised at my readout of 2,700 kcal (which is evidently high?). Anyhow, just trying to figure out this part of my life and would love any ideas…

  14. I can’t get either of these to work. :-(
    The first link takes me to a page with a PDF file and I can see the picture of the calculator but can’t click on it. The other one takes me to a page telling my to buy the women’s Heath an fitness app. Am I missing something? I’ve tried these links on my iPhone, desktop computer, and iPad. Help! I know from reading your blog that I’m likely under eating and have been on an off for years!

    • The calculator is confusing – it took me three attempts at going back to figure it out. You see how there is a little red square on each of the circles the numbers are in? You move that red square by left click holding it and you can then slide it around the circle – changing the numbers.

    • I know this is old, but I can’t get the second one to work, either. There is an option to purchase the app or subscription, something like that. First one worked, though.

  15. I just recently threw in the towel for “dieting” and am attempting to focus on body composition instead. I did not, however, carefully and slowly add back in calories, I just went whole hog and starting eating 2400-2800 calories a day that the calculator says I should be eating, even though my metabolism is seriously jacked up from being restrictive for a year (and getting nowhere, except killing my hormones). I have gained back all of the weight I lost (about 10 lbs), but I also gained back a normal menstrual period, as soon as I gained back some weight and ate carbs. I was definitely trying to maintain a weight that forced me to be too restrictive. Every time I splurged, the scale would shoot up.I don’t mind the weight gain as I just tell myself I need the calories to build muscle, and as long as it evens off somewhere and doesn’t keep adding on fat . Should I continue eating 2400-2800 calories a day, or should I back off and slowly add back in calories? I’ve been eating this way for about 3 weeks now. I seriously want to find a weight where I can continue to eat like this. It’s so much more freeing!
    I lift weights 3-4 mornings a week for about 20 minutes, whole body stuff like heavy deadlifts, squats, presses, lunges. I walk my dog for at least 30 minutes every morning and I have a fairly active job where I’m on my feet for 6-8 hours a day.

    • My gut says keep eating like this. The weight gain is part of the recovery process. I suspect that you may lose it again eventually. What’s important is that you are feeling and functioning better. Your body is telling you it’s happier with adequate nutrition! Listen to it! :)

    • PS: congratulations for your victory over dieting. I say celebrate with something carby and delicious.

  16. ok. according to this, I should be eating 2500 calories to mantain my actual weight.
    what about if what I want to do is to loose body fat. right now I’m in 31% bf. what do you think

  17. I love your website, I’ve just recently found you, and I’m so happy! I used these calculators and have a question. I’ve been steadily (slowly) losing weight from eating about 1,200 calories a day. I have now plateaued at 157 pounds, and can’t seem to go further. I work out pretty vigorously 5 times a week. The calculator said I need to eat around 3,000 to maintain my weight. However, if 1,200 is currently maintaining me at 157, then wouldn’t I gain at 3,000? Or have I jacked up my metabolism so much that it had to slow down because I’m starving my body? This weekend I’ve started adding more calories to test this system, but I’m having a hard time really understanding how it works. Thanks so much! I love this site!

    • I’m sorry for not responding sooner, Emily. You metabolism is probably a little jacked up, but it’s fixable. Start adding calories back in slowly, perhaps 100 per day per week. So week one eat 1300 a day, week 2 eat 1400 a day, etc, and work up to something more realistic, probably in the mid 2000′s. You may want to just maintain here for awhile and let your body adapt to being fed an adequate amount and heal itself. Undereating is so stressful on the body!

  18. WOW, even though what you’re saying makes complete sense, and it falls in line with my experience, it’s so hard to overcome decades of “programming” and accept that 2100-2300 calories will get me to (and keep me at) my ideal weight. (I am 5’3″, so obviously, my ideal weight is going to be a little lower.) I’ve done so many diets in the past that had me between 1000-1500 calories per day….and destroyed my metabolism to the extent that I would immediately and rapidly gain weight any time I went above 1300-1400 calories per day. The hard part, mentally, is getting past that initial weight gain and letting the metabolism normalize. That’s what I’ve been working on recently, thanks to your posts. Thank you for putting this out there!

  19. Pingback: Body Composition: That ‘Last Five Pounds’, and How to Deal With ‘Problem Areas’ | Go Kaleo

  20. What books do you recommend to read up on this info please? What books or authors or sites did you read when you were learning? Thanks!

  21. Thanks for this! These two calculators give me numbers that are different by about 1000 calories. I’m never sure exactly how much I really need to eat but since I want to build muscle I’m sure I have to eat more. Right now I eat around 2000-2300 per day and maintain but the first calculator gives me 4,100 (really..?) and the second somewhere around 3000. I do exercise a lot/am very active which the first one takes in to account better. I guess I will just experiment a bit and see what’s comfortable for me!

  22. Pingback: Q and A: Part 2 | Go Kaleo

  23. Thanks so much for this article! Calorie levels have always been something I have been perplexed by and have never known what I should be at.

    I am at a healthy weight (5’7″;135 lbs; 20% body fat) and am look for body recomposition. I don’t do any heavy weight training but instead do intense daily yoga sessions (I am actually going to be doing teacher training this summer). I have already seen some positive progress on my muscle tone since January. I also do some other light exercise like walking.

    I finally got one of those BodyBugg devices that measures calorie burn all day which shows that on my work days (I have a standing work desk and try to move around throughout the day) with yoga that I burn a little over 2500 cals (for 24 hours). On days when I am working from home (sitting) plus a yoga session 2200-2300 cals and on weekend days with yoga and other family activities I burn upwards of 2600 cals.

    My goal is to lose body fat. So what calorie level would you say I should target?

    I have been eating around 1500 calories. Should I be more at at 1700-2000 calorie level? I am afraid I will gain weight.

    • I upped my calories over the past week and have already seen positive change in my lean muscle mass. WOW!

      Thanks for you article again.

  24. If I was eating 2000+ calories a day I would gain weight rapidly. I really believe our calorie consumption is based on our height and energy expenditure, but even so, I am pretty active all day (dog walker by profession), doing at least 45minutes of strength training, I was eating at about 1800 cals a day and basically maintaining. The only way I was able to drop any weight was to lower my calories…can you further discuss this?

  25. THANK YOU for this! I’m so tired of hearing about people counting calories and saying things like, “I’m going eat 1200 a day!” There’s just so much wrong with that I don’t know where to begin. Thank you for spreading good info. :)

Comments are closed.