Exactly What Is A Low Calorie Diet?

By Jim F

The latest issue of New York Magazine has a large cover feature called “the diet to end all diets”. The author spends time living the Calorie Restriction (CR) lifestyle. The idea behind the CR movement is to prolong life by obtaining the optimum amount of nutrients while consuming the lowest amount of calories.

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New York Magazine, Oct 2006

The rather lengthy NY magazine piece provides an inside look at the lifestyles of a number of proponents – who seem to continually gush about the wonders of living a life obsessed with food.

A number of biologists have discredited the idea – and in my view the whole idea seems like a bad case of orthorexia.

Michael’s regimen of 1,913 calories a day is exactly that: 1,913 calories every single day, 30 percent of them derived from fat, 30 percent from protein, and 40 percent from carbohydrates.

Which brings me to the question: Exactly what is a low-calorie diet?

The article author bemoans the fact that he has been surviving on just 1,800 calories – and that this is “well short of the minimum 2,500 recommended for adult males”. I tend to think that daily calorie intake is closely linked with energy output – but even then – it is hardly an exact science.

Is 2500 Calories Too Much?
As for 2,500 daily calories – you may be interested to know that Scotland have just “officially” lowered their daily recommendations. The new allowances are 1600 for women and 2000 for men.

Has our fear of “starvation response” and yo-yo dieting caused us to overestimate just how many calories we actually need?

It’s Not Just About Calories
I personally feel that resistance and strength training play a significant role in preventing muscle wastage and metabolic sluggishness during lower calories. I also believe that calorie needs are linked to body composition rather than body weight. Those with more muscle mass need more energy to maintain that tissue.

Food and nutrient quality also play a significant role – 1800 calories of white bread each day will leave you feeling like a constipated whale.

What do you think?
Are daily calorie recommendations redundant? At what point are calories “too low”?
(thanks to Randee)

56 Comments

  1. Spectra

    I know that body fat percentage definitely depends on genetics, lifestyle, etc. and you shouldn’t fight your genetics all the time just to look a certain way. I happen to like running and my body doesn’t hold onto fat very well. I gain muscle when I gain weight, mostly because I’m so active. I typically eat quite a bit in a day too, about 2400-2600 calories a day (which is a lot for a 5’3″, 108 lb woman). But if you happen to maintain 18% fat on a diet of 2000 calories a day, that’s fine too. That’s why there are ranges that people fall into; all of them are healthy, just different.

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  2. David

    I have a measured RMR of 1832 cals/day. To need 2000 cals/ day, I would need an activity factor of <1.1. The World Health Organization had a real job on to produce actrivity levels below about 1.3*RMR. I was told by the gym I was underweight, back at 145lbs, with 6.7% fat. I'm now at 150lbs, just within the healthy range, but intend to gain 2-3 more,as I still look skinny and I want a safety net. My calorie prescription was 3114. I'm the sort that really struggles to gain. I do a lot of cycling, running and weight lifting. I think age makes it hard to gain weight, as I'm only 19. The recommendations above are suitable for sedentary individuals over 60 according to MyPyramid. Recommendations should be closer to 1800 for women and 2300 for men if you are going to base it on a sedentary population. The reason people are fat isn't because they eat 2000-2500 calories/ day. It's because they pay no attention and eat more or else aren't very active.
    I don't think calorie restriction works. On 3000 cals/ day, trying to follow MyPyramid, I unnecessarily lost from 156 down to 142 over a period of 9 months. I was perpetually cold by the end, and was in a state of near collapse on 2 occasions. It's been a job to regain the weight. On 3500 cals/ day, I've gained a mere 8lbs in 3 months. I have a freind who when he was my age couldn't get above 120 despite engaging in only moderate activity and eating 3500-4000 cals/ day. On the other hand, I know someone eating 700 cals/ day who's still overweight. Everyone's different. If the government wants to tackle obesity, they need to offer metabolism tests on the NHS not chuck ridiculously low calorie recommendations at us, which we won't be able to follow.

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  3. Jan

    JJ, sadly I don’t think that teens (female ones, at least) have body fat as a concern at all – it is all about pants size and the scale. But you are right, maybe it would have a negative impact on the rare male teens we do get here.

    I’ve settled for 21-22% myself… I’ve found I can only get to 18-19% when I also drop weight, I can’t at the weight I like best, so whatever. I am not gonna trade a better face and a not totally concave butt (which wouldn’t be a big issue if I didn’t have big legs, but big legs + no butt just doesn’t seem to go together) just to have more calf and shoulder definition.

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  4. jj

    Spectra,

    Sorry, I’m late getting back to you on this. But really, my point wasn’t about your size or your percentage. It was really that the right range for each of us varies with genetics, and may change depending on goals in other areas of our life (like having kids or acheiving an athletic goal). I just worry about giving the impression that lower is better, especially since we sometimes get younger people on here with eating disorder issues.

    And Jan, I’m like you, I’m around 20-21% right now and starting to look a wee bit on the bony side.

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  5. A different Nic

    Michelle, it sounds like you have disordered eating. I can tell you and tell you until I’m blue in the face that 1000 calories is nowhere near enough what you need, but if you really panic at the thought of eating more, I would look into some kind of counseling. Believe me, I’ve been there, and it is worth it.
    Check out this website: http://www.somethingfishy.org
    It’s really great. Good luck.

    PS Exercising is great. Don’t stop doing that…it is great for your body and your mind!

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  6. Jan

    Michelle – maybe if you stopped counting calories, you could do it? Focus on eating healthy foods. If you wanna speed up metabolism, why don’t you try doing weight training for the whole body? You could pick a DVD on it, or check out http://www.stumptuous.com/iron for some free weight training programs.

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  7. Michelle

    Well everyone in here has their opinion, so I would like to ask for ya’lls opinions about my diet. Im 17 years old (female) of course, but I started a diet in june this year 5mths ago. I was 198lbs now im 144lbs im medium bones dense, and im 5’5″. At first it was a normal diet no sugar, no junk , but then at some point it changed drastically to the point i was aiming for just below 800 a day. I had crazy dizzy spells and all those side effects. I was so obsessed that if I had to go into the 900s, I freaked out and feel bad. But anyway after a lot of talks with my family im now up to the 1000 and a little over points im moderatly active im to the point now that i just need to loose the belly so im doing arm weights leg stretches jogging a little dancing and 350 crunches a day. But im still not sure about how i can manage a little over a 1000 without have a mild guilty feeling, I honestly believe that I have developed a mental problem………..any suggestions thanks in advance ps. Im not belemic, anorexic, i don’t binge or use laxatives I just thinks it’s a slight problem with me accepting the calories

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  8. RedPanda

    “To further what Spectra’s saying, some people think that metabolism only goes down with less activity and less lean mass, not necessarily with age. I’m inclined to believe it.”

    I agree too. Those online calculators which tell you how many calories you need to maintain your weight assume that you lose muscle as you age. I plugged in my stats into one of those calculators and apparently I need to be 26 to eat as much as I do, which is interesting because I’m 50!

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  9. Jan

    Ryan made a good point. I forgot also fat intake, not only body fat. You need a decent amount of fat to be able to produce hormones correctly and in a balanced way.

    Now, too much body fat can often lead to the production of too much estrogen or in the case of people with PCOS, too much testosterone, both of which also affect fertility negatively. Not that it has anything to do with the “too low” body fat thing, but it is a much more common problem than being infertile from being too lean.

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  10. Spectra

    JJ–did you read my earlier post? I said I’m a bit underfat for my frame and I’m trying to correct it by eating more. Right now, I am at 12-13%, up from 10% where I was at the end of summer. I’m an athlete and a runner, so my doctor said %14 or so is about the lowest I should go. I do still menstruate at a BF % of 14%, so I know it’s fine. When I am at 18% body fat, I’m fine health-wise, but I get too heavy to run properly. I do know that when I do want to have kids, I’ll have to cut back on running and I’ll probably get a bit more fat on my frame.

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  11. Ryan

    Basically, the period and fertility stop when the body senses a crisis. There’s no point in breeding when there’s a food shortage or you’re constantly being chased by large animals, which you can simulate with heavy dieting and exercise. If the body feels it shouldn’t allocate the resources necessary to menstruate and so forth, then it won’t. This decision is influenced not only by body fat percentage, but also the amount of lean mass, the recent amount of calorie deficit or surplus, what kinds of calories and nutrients are being provided, etc.

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  12. Jan

    JJ, as long as the person is still having periods, there is no set number for body fat that is too low. Some people will never get below 18% (I’m one of those – I’m “stocky”, at around 19-20% I have bones sticking out all over the place), some people can have 12% and still get regular periods.

    Also, the fertility impact is usually because the person doesn’t only have low body fat, they also have an extremely low BMI. If a person has low body fat but still plenty of metabolically active muscle, there is no fertility impact.

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  13. jj

    “she has really great body fat, around 15%”

    I hate to be difficult here, but 15% is not “great” for a woman. It’s low. Not necessarially bad low, but it’s not something all women should aim at, especially if they’re thinking of having children. Below 18% can impact fertility for many women.

    I’m not criticizing Spectra in any way, I have no way of knowing whether that percentage is “great” for her body… it’s a fine level for many women. But just in general, 15% is not better than 18-20%.

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  14. Mary

    Jim: “…some of those who are very obese will often lose weight far more rapidly than that.” That may be true if they diet every day. If they diet every OTHER day, the amount of weight they lose weekly can be programmed precisely. So can the length of their plateau, because that is directly dependent on how much they lose in the first week.

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  15. James

    What the points I am about to bring up is about this:

    It not just about the calories, but it’s the balanced calories. Some people may need fat calories, carb calories, and some protein calories, but the rule of thumb is: everything in moderation…well, not everything. Hydrogenated oils are unburnable calories, simply because our body doesn’t have the tools to metabolize these synthetic trans fats. Remember my posting earlier on these so-called sick fats? Man, they make it tougher to burn calories, they cancel the benefits of omega 3 fatty acids, they lower HDL AND disable HDL function, and yes, a new research, they even weaken the immune system and may even cause osteoprosis.

    But the rule is: fruits, veggies, fish, chicken, and a little bit of everything else, including red meat. We even do need some saturated fats like butter and coconut oil or cocoa butter, but the important fat is omega 3 fatty acids, which further helps us to burn more calories as we exercise, and supplimenting with saturated fats enhances omega 3 fat function. However, you NEED to stay away from deep fried foods and any pasteries containing hydrogenated oils. Don’t just limit them, ELIMINATE them. Period.

    And Yes, you can gorge on 5000 calories on a holiday break, but don’t do it every day.

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  16. Ryan

    To further what Spectra’s saying, some people think that metabolism only goes down with less activity and less lean mass, not necessarily with age. I’m inclined to believe it.

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  17. Spectra

    Spectra: If you continued to eat the amount you’re eating now, you would gain weight as you aged, whether or not you were sedentary. But you won’t continue to eat this way. You will automatically eat less as you age.

    Uh, no, that’s not always the case. Age has little to do with metabolism if you are active. I know a lady who runs about the same amount as I do and she eats a LOT.

    Jan…I don’t mind you using me as an example at all. It’s very true. If I didn’t eat as much, I would lose muscle mass and therefore reduce my metabolic rate. To me, it makes no sense to eat less when it will basically cause me to eventually eat even less. I don’t think that you “automatically” eat less as you age…that’s complete BS.

    As far as the whole nutrient metabolism thing, it definitely varies from person to person, since everyone has differing levels of digestive enzymes. You can maximize the amounts of food you eat if you eat a lot of foods with fiber and protein and low on the “processed foods” scale.

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  18. Jan

    Mary, I beg to differ and to respectfully disregard anything you say, the same way I do for most doctors and nutritionists. And is “weight loss coach” sorta like “life coach”, which is a person who is like a completely untrained and unqualified “therapist” (or person acting as a therapist, to be more specific)? So are you a completely untrained and unqualified “nutritionist”, or are you an actual nutritionist or dietitian?

    I stand by my opinions. Of course you can lose weight eating 700 calories of apple pie a day. But if you change the kinds of food you eat, you could be losing the same amount of weight with a better body composition eating 1,700 calories. So why the hell would you wanna eat so little, if you don’t have to, especially when the effects on your body composition of eating a low-calorie diet will be of a lot of muscle loss, and little fat loss, making you unhealthier at your thin weight, than a weight lost by speeding metabolism and changing sources of food, that will keep your healthy lean mass? Do you tell your clients that body composition doesn’t matter as well?

    I’m not sure if Spectra will mind if I use her as an example but as far as I remember, she has really great body fat, around 15%. I doubt she would keep such a great body comp if she kept eating low calories, whether she minded the sources of food or not. I’m guessing it would be closer to 25% body fat. So as they say, the proof is in the pudding. Want to see the scale move, and not care how you look or how health is? Eat as little as you can and you too can look skinny flabby.

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  19. Jan

    Lisa, are you absolutely sure your thyroid replacement is at the correct levels for you? I don’t wanna go into a big thyroid rant here (I don’t have a working thyroid either), but the doctor has to be teste Free T3 and Free T4 as well as TSH. TSH is a lousy measure of thyroid hormones… it changes as much as 100% within the same day, for everyone, depending on the hour of the day you measure it.

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  20. Lisa

    To maintain 128lbs and being very active and exercising daily for 45min hard to 1hr….I had to keep my calorie intake at 800-950 about. And, my body would not lose any weight with that. I ate lots and lots of foods…because I went for high fiber, low fat, good for you stuff…veggies, fruits, non-fat veggie meats,etc….so, it wasn’t like I had 1 meal a day. I also think every body is different. I am amazed at some who can stay thin and eat 1600 calories a day and not be as active. I did have thyroid cancer and have no thyroid now. Maybe it is just my body..figures…probably! Now, I am at 1300-1600 a day and need to lose! Grrrrrr. I don’t get it. I just figure to each his own…there probably is a “in general” deal, but that doesn’t apply to everyone.

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  21. Jim

    I don’t think it is an exact science. A calorie as a unit of energy – sure that’s absolute science. But the way our body metabolizes different nutrients – and adapts – that’s not so exact.

    As for the 2 pounds per week rule – I believe that is a good rule of thumb except some of those who are very obese will often lose weight far more rapidly than that. Of course, who can judge the long term health outcome without properly studying the situation many years later.

    Anyway – it’s surely all about feedback. If something is working – stick with it. If it’s not – then change it.

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  22. Heather

    It’s hard to say, since every person is different.

    And then if my experience shows anything, your body changes as you go along… 🙂

    Confusing, the human body.

    I use DietPower to help me know what to do.

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  23. jj

    Honestly, I think blanket calorie recomendations are useless. The key to long term weight loss and weight managment is to know thyself. Emotionally, how your body reacts to certain foods, and yes, the calorie level that *you* maintain *your* weight at. We all have a different frame size, muscle mass, food preferences and allergies and activity levels.

    The Scotland recommendations surprise me. I’m a very short woman and I work out fairly hard on a very regular basis (i.e. I’m far from average on both fronts) and 1650 is about my maintence calorie level. A woman who’s taller than me and moderately active would probably be at a calorie deficit.

    I think there’s some worth in calorie restriction, although personally I wouldn’t like to know what I look like at an 18 bmi. But replacing zero nutrient junk foods with high nutrition foods and trying to get a well balance of nutrients from whole foods are both strategies that lead to a greater level of saitety (sp?) at a lower level of calories and better overall nutrition. And while I wouldn’t want to live forever (yeeech) being able to have just 4 or 5 more years with my family, in good health, would certainly be a wonderful gift.

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  24. Mary

    Jim: “I tend to think that daily calorie intake is closely linked with energy output – but even then – it is hardly an exact science.” But it is an exact science, Jim. I use it in my weight loss coaching.

    Jim: “Has our fear of “starvation response” and yo-yo dieting caused us to overestimate just how many calories we actually need?” In a word, Jim, yes. I’ve had clients who followed the calorie guidelines of their program, and who didn’t cheat, yet who didn’t lose an ounce. If the calorie allowance you’re using isn’t getting you anywhere, it’s too high for you. Period.

    Calorie needs are linked to our metabolisms, which become more efficient as we age. Here’s the kicker: some 20-year-olds have the metabolic level of some 60- or 70-year-olds. I expect it’s for genetic reasons. It’s my job as a weight loss coach to find out what that level is, then go from there.

    Jim: “At what point are calories ‘too low’?” Calorie allowances are too low if you lose weight at a weekly rate that’s unsafe. I don’t allow a client to lose more than 2 pounds/week.

    Nic: You would lose weight in a coma if your calorie intake were below what you need to maintain your weight at X pounds. That amount depends on your metabolic level.

    A Different Nic: You’re quite right. You can’t really say that a man needs X calories and a woman needs Y calories. The amount needed to maintain one’s weight has nothing to do with one’s sex. There is a standard formula I use that takes into account several things, age being one of them. But it’s still a matter of trial and error until I find out the client’s metabolic level.

    Cecilia: When you become an adult, that 1300 calories will get lower, not higher. And even if your weight remains the same, that amount will automatically lower every few years.

    RedPanda: You didn’t say what weight you maintain on 2200 calories/day. But if you’re content with your weight, it’s the right amount of food for you.

    Spectra: If you continued to eat the amount you’re eating now, you would gain weight as you aged, whether or not you were sedentary. But you won’t continue to eat this way. You will automatically eat less as you age.

    Jan: I know how much this offends some people but when it comes to weight loss, the amount of calories is more important than the source. If you’re talking about nutrition, it is certainly important what you eat; if you’re talking about weight loss, it isn’t. If you eat fewer calories than you need to sustain your current weight, you can lose pounds eating nothing but apple pie. I don’t recommend it but it does work.

    Howie Jacobson: “The US food industry produces over 3900 calories per day per person – about double what’s needed, on average.” Howie, there isn’t any average. Different metabolic levels need different amounts of calories. Even people who are the same weight and age can have different metabolic levels.

    Mel: “I’m a 1200 calorie a day diet…and I’ve lost about 45 kilos. I think it will be difficult bringing the amount up once I’m at my goal weight.” You’re right, Mel. It will be difficult because you won’t be habituated to the number of calories you need to maintain that 45-kilo loss. It’s better to find this out before you even start dieting. If you find it out then, you won’t need a maintenance program after you reach your goal.

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  25. Jan

    blubbah, indoor cats hunt too. They eat moths constantly, but I think those are pretty low-calorie, haha.

    Mel, I admire you. I’d die on 1,200 calories a day. Gosh.

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  26. blubbah

    Spectra, I agree, but one significant difference is that we tend to get to choose, whether consciously or not, what we’re eating, whereas pets get what we give them, both in quality and amounts. (Some outdoor cats hunt, but they’re usually fed kibble on top of that.)

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  27. Mel

    I’m a 1200 calorie a day diet…and I’ve lost about 45 kilos. I think it will be difficult bringing the amount up once I’m at my goal weight.

    Things that worry me are putting on weight, yoyoing, keeping up the healthy eating…

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  28. Spectra

    Humans AREN’T the only animals with the problem of overconsumption. Domestic pets are getting fatter and fatter as well. Wild animals have to search for their food; domesticated ones are fed a diet of processed pet foods. Ideally, dogs should be fed a diet of raw meat and bones and hide…like in the wild. Just like humans should be eating mostly unprocessed vegetables, fruits, meats, and grains. UNPROCESSED is key!!

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  29. Ryan

    “I eat a whole-foods, plant-based diet, and I’ve found that calorie counting simply disappears as an issue when you keep out of your body foods that don’t belong in your body.”

    I’m finding the same thing works with a whole-foods, animal-based diet too.

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  30. Howie Jacobson

    To me, the key question is why humans, with our big brains and big calculators and big computers, can’t manage to keep our caloric intake and output in equilibrium. In other words, why are humans and our pets the only creatures on the planet who consistently overeat? We’re not the only ones living with caloric abundance, but we’ve lost our “I’m full, so I should stop eating now” mechanism.

    Four theories:

    1. The processed foods – concentrated calories and artificial ingredients – confound our circuitry. Like putting an elephant on a 5-lb postal scale.

    2. We’re eating on the run, distractedly, so we’re taking no pleasure in our foods. Maybe pleasure is the nutrient we have to get enough of in order to stop naturally. Ever eat a single M&M, slowly? Like really slowly? Try it, and you’ll find you won’t have a craving to eat a pound at a sitting.

    3. Professor Wansink’s book Mindless Eating suggests that clever marketing may induce us to eat more than we think we’re eating. Huge plates, big bowls and spoons, Super-Sized portions, etc. are turning us into a nation of unintentional gluttons.

    4. Michael Pollan (The Omnivore’s Dilemma) and Marion Nestle (What to Eat) both look at our overconsumption with a naturalist’s eye. The US food industry produces over 3900 calories per day per person – about double what’s needed, on average. To grow and satisfy shareholders, these companies will do everything they can – are required by LAW to do everything they can – to get us to buy and then consume those extra calories.

    I eat a whole-foods, plant-based diet, and I’ve found that calorie counting simply disappears as an issue when you keep out of your body foods that don’t belong in your body. No dieting, no counting, no obsessing. Just improved health and a normal physique.

    Is it calorically restricted? I don’t have the slightest idea – I eat until I’m satisfied, and I don’t worry about it. Like every other animal on the planet does.

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  31. Jan

    I agree with Ryan, Jim, Red Panda, and Spectra. In my own very unscientific experience, source of calories matters more than calories. When I was eating not-so-clean (no sugar, no junk, but still eating a few diet foods), at 170lb with weight training and cardio, I needed to eat 1,400-1,500 to lose weight. As soon as I cleaned up my diet a bit, not anywhere close to bodybuilding perfection cause I’m a very undisciplined eater, but just quitting about 60% of the diet processed foods I used to eat, I started losing so fast I had to keep upping calories, and kept them at an average of 2,000 a day until I reached my goal weight, and then had to up to 2,500 for maintenance.

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  32. Spectra

    Ryan and RedPanda–I tend to agree with you both. Lean body mass plays a huge role in how many calories are enough. I eat around 2400 calories a day and I maintain just fine…I’m even a bit underfat for my frame size (which I’m trying to correct by upping to 2800 calories a day). I am very active though, so I’d guess that if I continued to eat this way and be very sedentary I’d probably gain.

    That being said…the CR movement does have a valid point when it comes to nutrient maximization vs. calorie minimization. I try to do that so I can eat more of the foods I like. Spinach, for example, will provide more vitamins than say, white bread with a fraction of the calories. So if you eat a spinach salad instead of a PB and J on white, you’ll save calories, feel about as satisfied, and get more nutrition so you’ll feel better. I think processed foods in general are contributing to our eating too many calories with not enough nutrients. Therefore, our bodies always feel malnourished and are “starving” even when we’ve eaten.

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  33. RedPanda

    “I personally feel that resistance and strength training play a significant role in preventing muscle wastage and metabolic sluggishness during lower calories. I also believe that calorie needs are linked to body composition rather than body weight. Those with more muscle mass need more energy to maintain that tissue.”

    This has been my experience. When I was obese and never exercised, I would maintain on 1200 calories a day. Now that I “lift heavy” (and do a moderate amount of cardio) I maintain on 2200 calories a day – which is a lot of food for a 5’3″, 50 year old woman. I monitor my body composition with calipers: when I don’t eat enough calories, or don’t eat enough protein, I lose muscle.

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  34. Cecilia

    I’m no expert, but I think that 16-1800 calories is fine, whether you’re actively trying to lose weight or not. Lately, I’ve been doing about ten minutes of exercise each day and usually stick to about 1300 calories, give or take a few. If I eat more than that, I get really overactive and less makes me feel tired. By the time I’m an adult (I’m 16) that 1300 that works perfectly for me will probably be a little higher. That ‘magic number’ is different for everyone, though. One of my friends (17) weighs 98lbs and eats at least 2000-2500 calories a day. No anorexia, no dieting, no exercise. Just a high metabolism.

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  35. iFitandHealthy

    At what point are calories “too low”?

    If we are not talking about weight-loss, the calories are too low when your intake is below your resting metabolic rate. In other words, if you do not want to lose weight, but you eat less calories than you need to maintain your current weight – that is too low.

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  36. Lemaloon

    The basis of the CR fad is animal studies showing that rats and mice fed very low calorie diets can as much as double their lifespans. Usually rodents are constantly breeding – but if they’re starving they stop reproducing. Surprise! Constant breeding really takes it out of you. These poor animals also spend all their time huddled in their cages conserving energy. What a rotten life. I wouldn’t wish that on any human.

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  37. A different Nic

    When I was in treatment, I was asked by my nutritionist how many calories a person needs if they are not moving at all and are in a coma. I thought the answer would be about 800. I was shocked to learn that the real answer is 1200-1400. If you’re in a coma. If you’re moving around at all, even if you’re sitting on your butt, you need more.
    I don’t think I can really say “A man needs X calories and a woman needs Y calories”. It varies so much from person to person, I don’t think there is really any standard formula one can use.

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  38. Nic

    I think this just proves that people are becoming less active. I believe the 2500 calories is based on having an active lifestyle. We’re sitting on our butts! Hence the 1200 calorie guaranteed weightloss diets. You could lose weight in a coma with that one.

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  39. Ryan

    I’m losing weight on at least 3000 calories a day. I’m carrying quite a lot of lean mass for my height though. If you’re sedentary and maintain weight on X calories of processed food, then in my opinion, eating below X calories is too low. Instead, increase food quality and start doing cardio and strength training. This will create the deficit. If you insist on restricting calories, never do so for more than 2 or 3 days in a row, and never go below 20% of your maintenance.

    Oh, and if any diet was “the diet to end all diets”, it would be BFFM.

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  40. jodi

    i think when your body can’t function anymore, is when calories become too low… some people don’t realize that the more you restrict yourself, the harder it will be to lose weight – if that is their goal… your metabolism needs fuel in order to work and that’s as simple as you can get… i think going under 1200 (for women) is too low, esp. if you’re also exercising, and feel 1500-1800 is acceptable… that’s what i do anyway and it seems to be working… :o)

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