If I'm limiting my carbs to 20-30 a day, how much should I factor in my overall calorie intake?

January 28, 2011 11:27 AM

DietFilter! I want to lose 15-20 pounds by this autumn. If I'm limiting my carbs to 20-30 a day, how much should I factor in my overall calorie intake?

After reading the Gary Taubes books, my boyfriend and I cut down on our carbs, first going under 20 carbs a day, then falling off the wagon for a bit, and then resuming a lowish-carb diet. Bread, rice, pasta, and especially sugar are very rarely consumed. We eat mainly meat, tofu, vegetables, and nuts. I've lost 20 pounds in a year, the dude lost about 35.

When I put my height and weight into a calculator that only figures out how many calories I'd need to lose 1 pound a week, it says 1200. This is, of course, not counting the fact that I'm limiting carbohydrates. I know that one must maintain a calorie deficit even on a low carb diet, but for how much? 1200 calories seems awfully low to begin with, but that's because I'm already within the normal weight range for my height and would need to restrict caloric intake by a significant margin to keep up the weight loss. If I lost 20 pounds, I'd be on the lower end of the healthy weight spectrum for my height.

So, low carb diet on 1200 calories? Or can I have more leeway when I restrict carbs?

posted by Viola to Health & Fitness (29 answers total)

I think it's pretty much calories in minus calories out. The carb/fat/protein balance effort is to make sure you get the right nutrition making the most of your calories and to optimize the neural signals that control your sateity/hunger levels.

If you are going to eat a Kcal of something make it something that really feeds you and preferrably makes you feel satisfied and full the longest. In my experience, that is a good balance of all three. Attempts to "game the system" rarely result in lasting benefit.
posted by cross_impact at 11:39 AM on January 28, 2011

I'm a little confused about your question, but I'll just point out that calories are much more relevant to weight loss than carbs are. Aside from relatively minor personal inconsistencies and the fact that calories (as reported) are an estimation, it doesn't matter where the calories you eat come from when it comes to losing weight.

You should find a better way to calculate your basal metabolic rate (BMR) if you want to really figure out how many calories you need/should be eating each day. The best way (my opinion) involves keeping strict track of your calories for a full week of normal activity and weigh yourself at the beginning and end.
posted by aganders3 at 11:41 AM on January 28, 2011

Response by poster: I think it's pretty much calories in minus calories out.

I'll just point out that calories are much more relevant to weight loss than carbs are.



Without inciting a huge debate about this (and really, thank you for answering!) Taubes' books provide a lot of evidence suggesting that calories in, calories out is a pretty terrible dieting philosophy. This has proved true in my personal experience of cutting carbs vs. cutting calories as a whole. I'll head off further CICO suggestions by saying that I need to go low carb to drop weight.

To clarify, I'm mainly wondering how drastically I need to cut calories when my diet is already very low in carbohydrates. Apologies for sounding convoluted.
posted by Viola at 11:50 AM on January 28, 2011 [7 favorites]

Another book that has some food quantity rules that goes very well with a macronutrient-control philosophy is the Zone Diet, Barry Sears. He doesn't go strictly on calories, but it's probably worth picking up cheap or finding at the library to take a look - basically, his method is to calculate how much you eat based on your lean mass rather than your overall weight.

It also might be worth a look at one of the various Paleo books - the Cordain one is the foundation, but Robb Wolf is engaging and also very heavy into the biochemistry of things. (I've read his blog, but not his book as of yet.) You may get better results making further changes to your food quality rather than futzing with quantity.

And... I dunno if it's worth asking, but why exactly do you want to be "on the lower end of the healthy weight spectrum for [your] height"? Or are you just guessing at the number for now? Because thinking about body composition may also get you more bang for your buck, aesthetics-wise. (If you're cutting weight for a wrestling meet, well, so be it.)
posted by restless_nomad at 11:56 AM on January 28, 2011 [1 favorite]

The difficulty is that asking how drastically you need to cut calories is intrinsically a question about "calories in - calories out". There is no other way to answer the question except to make a judgment about that equation.

To lose a pound a week of fat you need to shed roughly 500 calories a day. So figure out how many calories you are eating when you are maintaining current weight and subtract 500 from that. There's really no other way to do it unless you want to go with trial and error.
posted by Justinian at 11:57 AM on January 28, 2011 [2 favorites]

it's hard to say without you describing your physical output -- if you just sit on a couch all day, 1200 calories / day might not cause you to lose much weight, but if you are exerting yourself physically in some way, then of course your daily caloric requirements will increase. if you stay below those caloric requirements, you will lose weight (all other things being equal).
posted by modernnomad at 11:57 AM on January 28, 2011

The idea behind low carb is that if the carbs are low enough the calories don't matter. Not wanting to get into the whole CICO argument either, here's a link to Gary Taubes' blog where he discusses that low carb diets are unrestricted calorie diets.
posted by artychoke at 11:58 AM on January 28, 2011 [1 favorite]

15 to 20 pounds in 9 months is totally reasonable, and 1200 calories sounds a bit low.

Something that people forget when planning diets is that this is how you're going to eat for a while. If 1200 calories isn't enough food for you, you're going to fall off the wagon. Depending on your current height/weight (and that information would be helpful,) you'd be fine anywhere from 1400 to 1800. You have a lot of time to lose this weight, and there's no need to cut calories that drastically.

I think you have more leeway not because of the carbs thing, but because for most people, 1200 calories is not enough. You need to fuel your body, especially if you're working out.

IAMAD(octor/ietician.)
posted by punchtothehead at 11:58 AM on January 28, 2011

I'm not at all an expert on any of this dieting business (trying to figure out the best way myself)... but I would think that if you're trying to drastically cut calories on a diet very low in carbs, that doesn't sound very healthy or sustainable.

At this point, perhaps a rigorous physical exercise regimen may help you lose those last 15-20 lbs in a healthier way than cutting calories can. Further cutting calories would also considerably slow down your metabolism, hindering steady fat/ weight loss progress.

My 0.02.
posted by Everydayville at 11:59 AM on January 28, 2011

Gary Taubes position appears to be that you could eat 5000 calories a day and lose weight as long as the carbs are low enough; this would appear to be factually untrue.

I just don't see any way to answer the question "how many calories do I have to cut out of my low-carb diet to lose a pound a week" without addressing, well, how many calories you have to cut out of a low carb diet to lose weight. It's possible that restricting carbs in and of itself will restrict calories so take that into account.
posted by Justinian at 12:05 PM on January 28, 2011 [2 favorites]

No online calculator based only on your height and weight, and certainly no one on metafilter who doesn't even have that info, can tell you what the optimum caloric intake is for you to reach your goals. Your metabolic rate depends largely on your body composition (i.e. lean mass vs. fat) and activity level as well as the makeup of your diet. Even a calculator that took more data into account will still only give you a rough estimate. If you want to figure this out for yourself it will take a little trial and error. Choose a ballpark figure that seems like something you can stick with, do so for a week or two, and observe the results. If you gain or maintain weight, reduce your caloric goal or increase your activity. If you lose weight and feel satisfied with your diet, keep at it.

restless_nomad's point about body composition is well-made; weight loss in and of itself won't necessarily make you look, feel, or perform better, depending on how it's achieved. Also, while Gary Taubes seems to be on to something, his work is of course not the last word on nutrition and weight loss; I found some of the commentary here to be interesting.
posted by Anatoly Pisarenko at 12:06 PM on January 28, 2011

I'm generally a "calories in/calories out" kind of guy, but I respect your personal experience and your thread so I will try to frame this in a way that we can agree on.

In my philosophy, the issue is that for you the calories estimated (what you see on a "Nutrition Facts" panel) for a gram of carbs is (perhaps vastly) under estimated. Similarly the calories estimated for a gram of protein or fat may be over-estimated for your metabolism. So if low-carb is working for you, keep at it!

I'd say feel free to give your self some leeway on "total calories" for the first month, and if you're not seeing the results you want (1-2 lb/week I assume, which is healthy weight loss) then lower your calories further by either cutting more carbs or overall food intake.

On that note (and I'm sure you've heard this before) I'm going to be "that guy" and chime in here with the suggestion that body weight is not the best metric for setting goals. If you are exercising (which you should be -- cardio and weights) you will end up putting on muscle and it can distort your impression of progress if you're just going by weight. Consider setting strength/endurance or even appearance (using e.g. a tape measure or photos) goals instead of weight-based goals. This becomes more true the closer you get to your goal weight!
posted by aganders3 at 12:07 PM on January 28, 2011 [1 favorite]

Response by poster: More info: My current weight is 128 and my height is 5'3". I used to weightlift three times a week (partly as a way to maintain muscle and lose fat), but my gym is so damn expensive that I'm taking a break until my finances coalesce. Clearly when I start lifting again, I'll readjust my food consumption.

If I lose 10 pounds and feel healthy and happy with how I look, I'll definitely stop dieting and work to maintain my ideal weight. I'm throwing out 15-20 pounds as a high goal that I can taper down as I go along.

I work with young children, so I'm a lot less sedentary than someone sitting in a desk chair, but I'm not exactly a lumberjack, either.
posted by Viola at 12:11 PM on January 28, 2011

Totally agree with aganders3 that in this case, you're going to be your own science experiment. I count calories (and it automatically tabulates my protein/fat/carbs %) and I usually stick to 40/30/30 carbs/fat/protein %. Earlier this fall, my calorie range was like 1700-2000, and I really wasn't losing weight very quickly, or at all. Now I set it at 1500-1800, and my weight loss is much more regular and predictable. I personally think 1200 is quite low, unless you are a very petite person or totally and completely sedentary.
posted by sararah at 12:16 PM on January 28, 2011

Calorie consumption is much more determinative of weight loss than carb consumption. Ultra-low carb diets are effective, but not sustainable. The trick is to restrict calories while curbing hunger. This is best accomplished with a mix of high fiber foods (bran cereals, legumes, etc.), high volume foods (green vegetables), lean proteins and a limited quantity of beneficial fats (nuts, seeds, very small portions of olive oil). It is important to eat these in combination at least twice a day, and to have at least three additional small meals. With these foods, it is possible to sustain calorie consumption of 1200 to 1800 calories a day without physical hunger. Cravings for fats and sugars will diminish, but will never disappear entirely. These principals are explained in two books by Susan Roberts, a researcher at the Tufts Center for Human Nutrition and Aging - "The Instinct Diet" and "The I-Diet".
posted by pavi at 12:22 PM on January 28, 2011

Best answer: The way I understand Taubes, calorie restriction is a bad idea and does not work, because "calories in/calories out" is patently wrong.

In my personal experience, if you limit carbs as low as you do right now, you don't need (and in fact, should not) try to limit, or even count, your calories. That way, you're just going to get crazy cravings and fall off the wagon. Also, do you plan to count and restrict calories for the rest of your life? Really? If not, this strategy is not sustainable in the long term anyway.

I want to lose 15-20 pounds by this autumn
My personal opinion: Getting to a healthy weight, and getting a healthy relationship towards food, does not work that way. Your body is going to do this on its own terms, or not at all. As the old African saying goes: "Grass doesn't grow faster when you pull it. "
posted by The Toad at 12:23 PM on January 28, 2011 [4 favorites]

Your goal would put you at the thinnest possible weight without being underweight, according to the BMI charts. In my opinion, this would only be healthy if you were a naturally tiny individual with a very small frame. I don't think this would be the "lower end of healthy"; I think it's verging on an eating disorder. More importantly, it doesn't sound very sustainable in the long run.
posted by yarly at 12:36 PM on January 28, 2011 [4 favorites]

Best answer: The way I understand Taubes, calorie restriction is a bad idea and does not work, because "calories in/calories out" is patently wrong.

That's how I interpreted him too. (I just finished Why We Get Fat.) As I understand it, Taubes says that low-calorie diets do sometimes work, but only because they are necessarily limiting carbs as well. So the calories that matter are the ones coming from carbs. I think in theory you could eat as many calories of fat and protien as you want, if you are eating so few carbs, and still lose weight according to his theory.

My guess, though, and this is just based on personal experience, is that if you're eating as much as you damn well please you will eat a lot less on a high protein/fat diet than a high carb one. I know I could eat an entire French bread if I allowed myself to do so, but there's no way could I eat more than, say, three eggs at one sitting, or even in one day. So I think that perhaps he never gets into the question of "how many calories of fat and protien can I eat?" question because he thinks that your body won't want enough calories on that plan for this be a problem.
posted by DestinationUnknown at 1:03 PM on January 28, 2011 [7 favorites]

That's certainly been my experience with high fat/high protein diets, particularly ones where I'm really careful about the quality of the food. However, that's assuming you have a reasonably functional appetite meter, which isn't true for everyone - and that can get particularly jacked up with junk food.
posted by restless_nomad at 1:05 PM on January 28, 2011 [1 favorite]

1200 calories sounds very low (far too low, in my opinion, unless you are over age 50 and probably even then) for a low-carb eating plan. General practice with low-carb plans is to eat to satiety when you are hungry without much concern for calorie count. That's one of the better-known appeals of low-carb eating. As long as they're not going overboard with foods that are both high-calorie and very easy to eat in excess (cream, nuts, etc.), most low-carbers in good health don't need to worry much about restricting calorie count, and in fact shouldn't consciously restrict calorie count.

There are exceptions, of course. Some people find through experience with low-carb that they do need to keep an active calorie count due to age or personal quirks of metabolism/appetite.

Taubes' book is interesting, but you need more information on how people actually practice low-carb eating. Please pick up a book or two on low-carb eating plans or visit one of the active websites, e.g., http://forum.lowcarber.org, http://www.marksdailyapple.com, and many others.
posted by hat at 2:49 PM on January 28, 2011

Limit your carbs and eat to satisfy your appetite. Don't count calories or anything else (caveat is that you can consider counting protein when you start lifting again). Most people I know who are mildly active and limit carbs as severely as you find that they need to consume large quantities of fat in order to maintain their weight (and that's fine).
posted by telegraph at 3:47 PM on January 28, 2011

It is going to be harder to lose weight now that you've already lost a bunch and are closer to being at a healthy weight. Cranking up the exercise will help a lot. Last spring, I lost a ton of weight when I combined low carb with lots of high intensity exercise--though, notably, it was only three days a week, but it was a super intense bootcamp workout with muscle and heart work.
posted by bluedaisy at 4:15 PM on January 28, 2011

Bernstein Diabetes Book has the advice you are looking for. His plan is suitable for non-diabetics.

If you want to eat carbs that are proscribed on that plan, try a glucose meter. It is a good weight loss tool for anyone. You won't be using it long term; one box of strips will be plenty.

Also, if the idea of not counting anything appeals, look at the Get Started page on the PaNu blog. Perfectly compatible with Taubes' ideas.
posted by egk at 4:16 PM on January 28, 2011

I really like Four Hour Body for its discussion of calories. Despite the commentary above, it really is not calories-in/calories-out for weight loss. The science supporting that conclusion seems extremely suspect.

The argument in the book is that basically, the reason scientists talk about calories is that they are easy to measure. Not from the book, but my take is that your body is not a machine that burns stuff. That's not how the chemistry works at all. But yet that is what a "calorie" is, which is defined as "(a unit of heat equal to the amount of heat required to raise the temperature of one kilogram of water by one degree at one atmosphere pressure" cite.

Disregard calories, limit carbs, you'll lose the weight. I'm down 10 pounds in a month on Tim Ferriss' diet, eating like a pig without the calories.
posted by Invoke at 4:20 PM on January 28, 2011 [1 favorite]

Er, without the carbs. Sorry, easy to fall back into the standard verbiage.
posted by Invoke at 4:22 PM on January 28, 2011

Seconding the Mark's Daily Apple recommendation, and adding another.

I find weight control to be pretty easy when I eat like this. To answer the OP, I don't count calories - just wait until I'm actually hungry to eat and occasionally skip breakfast if I want to lose fat.
posted by Earl the Polliwog at 7:09 PM on January 28, 2011

calories in calories out

eat lots of fruits, veggies and lean proteins.

I lost 50 pounds in 3 months by doing this and walking several hours a day.

also the ipod calorie counting app helped train me to understand how many calories I was consuming.

Also made me really eat natural foods because of the Monsanto effect on packaged foods.


Really is quite easy to do. I never felt like I was killing myself at all.
posted by tarvuz at 3:01 AM on January 30, 2011

also I think eating carbs HELPED me lose weight because I had more energy to exercise.
posted by tarvuz at 3:03 AM on January 30, 2011

Good for you on the weight loss so far. I'm currently maintaining my 80-pound weight loss (5'4", I stay between 130-133 lbs) with the same low-carb that I lost with. I log my foods occasionally, and it looks like I'm maintaing around 1800 calories per day, and usually around 20-40 grams of carb. Looking back at some old logs, I ranged anywhere from 1400-1800 calories per day while I was losing.

I didn't count calories at all during the weight loss -- I just counted carbs. I ate whatever low-carb fare I wanted, to the point of satiation. Sounds like you're on a good track so far. Just know that the lower your weight gets, the slower it comes off.

Regarding goal weight -- at 5'4", I know a lot of people set 120 as a goal. I thought about it, but once I hit 130, I decided to settle in. I'm a pear shape, so you can count all of my ribs clearly, while I still have some junk in the trunk. Were I to lose that last 10 pounds, my upper half would look horribly emaciated. I think it's better to have a size for a goal instead of a specific weight. Also, if you're working out, you may have a few more pounds of muscle mass instead of fat, which would skew using a certain weight as a goal.

I'd also add in that the type of carbs matters. Way back when, I used to eat low-carb tortillas. I came in under my carb goals for the day, and they were technically diet-legal, but I wasn't losing as fast as I'd hoped. I've since dropped all wheat from my diet, and on higher carb days I still avoid it -- I stick with potatoes, rice, corn, and anything without gluten. Even on days where I well exceed 40 grams of carbs, I don't gain without the gluten.
posted by themissy at 12:49 PM on January 30, 2011