I'm a strong advocate of not counting calories, because your body has a built in mechanism for maintaining a specific fat level: leptin.

The hormone leptin wasn't discovered until 1994--just 18 years ago--so there's plenty of conventional diet wisdom that doesn't take leptin into account. That's why, imho, conventional diet wisdom (including counting calories) doesn't work.

Leptin is a hormone produced by your fat cells. The more fat your body carries, the more leptin in your blood stream. The less fat your body carries, the less leptin in your blood stream.

Your brain has the ability to detect the amount of leptin in your blood stream, and reacts to the amount.

• High leptin levels result in increased metabolism and reduced hunger.
• Low leptin levels result in decreased metabolism and increased hunger.

The practical result is your body regulates your body fat based on your leptin level.

There are a number of things that can interfere with this fat regulation system.

1) High triglyceride levels have been shown to prevent leptin from crossing the blood/brain barrier. This fools the brain into thinking there isn't any leptin in the blood stream. The result: the brain thinks you need to add fat, so it decreases your metabolism and increases your appetite (to a screaming intensity).

2) It's one thing for you to eat fewer calories because your brain has reduced your appetite due to high leptin levels. It's another thing to eat fewer calories when your body isn't telling you to do so. When you reduce your calories your body thinks there is a famine, and it goes into survival mode. It doesn't matter if you carry 100 pounds of extra fat, your body is going to try and hold onto as much as possible so it can survive the famine. And, how does it doe that? By reducing your metabolism and increasing your appetite--the exact opposite thing you want when you are trying t lose weight.

3) Overeating will still cause you to gain weight. When your body is trying to lower your fat level, there will be days when it reduces your appetite to very low levels. If you track your calories you won't be able to believe that you can get by on so few calories (even though you are not hungry). The result: you're going to eat something (even if you aren't hungry), because the analytic part of your brain just knows you need to eat more calories.

Problems #2 & #3 are a direct result of counting calories. Sure, you can lose weight by counting calories (a lot of people have), but to me counting calories is part of the "just be disciplined and will it to happen" mindset. You can "twist your body's arm" and force it into shape--for a while. But, in the end, your body is in control and will have its way. It's better in the long run to work with it rather than against it.

As far as #1 goes, any good paleohacker knows that eating lots of carbohydrates results in high triglyceride levels. Which prevents leptin from crossing the blood/brain barrier, which causes your brain to think you don't have any body fat, which results in a lowered metabolism and increased appetite (is it any wonder that the typical overweight person is sluggish and always hungry, even though they are carrying tons of extra fat?)

If you've followed the government's food pyramid and eaten high levels of carbs all your life, your body's letpin/weight-regulation mechanism has probably never worked as intended. This is why paleo allows people to lose weight effortlessly. It creates the circumstances that allows your body to regulate your fat level naturally--the way it is supposed to be regulated.

That's the long term answer to keeping your weight in line, not counting calories, discipline, will power, or trying to bend your body to your will.

Not everyone in the Paleo world says calories don't matter. In fact I would say most agree that at some point calories do matter.

Paleo, for most, appears to lower caloric intake. This could be due to food reward, if on low carb the fact your avoid a macronutrient from your diet, more exercise, etc.

I would say, you goal should be to monitor you caloric intake. What you want is a natural way to eat at your maintenance w/o measuring, counting, worrying about every calorie. Hopefully, a clean paleo diet can get your there or at least close enough. Plus add in the lifestyle changes going Paleo (being more active, getting good sleep, managing stress).

I think the question is whether or not starvation is a healthy, sustainable lifestyle.

Conscious calorie restriction is mild, self-imposed starvation.

I think if Paleo/low-carb diets require calorie-restriction in order to be successful, they don't offer any benefit for weight-loss over conventional calorie-restricted diets. In fact, I think you can make a pretty good case that calorie-counting is the very antithesis of the Paleo rationale which, as I understand it, is that given an appropriate food environment our bodies can regulate food intake on their own.

It's also possible that years of an inadequate or harmful diet might render those mechanisms inoperable, and in those cases conscious calorie restriction may be necessary, but only as a last resort.

Regarding life-extension, I for one don't want to spend my life in a chronic state of mild hunger and lowered-metabolism just so I can spend an extra couple of years drooling into my lap.

Also, ad-lib low-carb diets have been around since the early 70's (Atkins), long before Gary Taubes wrote "Good Calories, Bad Calories". Gary Taubes is a journalist, not a scientist, and he didn't create the carb/insulin theory of obesity. He believes that it's true, and he writes about it.

The point of telling folks to stop counting calories is to reverse the concept that caloric intake is the determinant of overall health and/or bodyweight. Contemporary biochemistry and neurogastrointestinal physiology is demonstrating very consistently that many things matter far more than number of calories.

Particularly when folks are transitioning from SAD to paleo/primal, what is required is a shift in mindset from counting the number of calories to counting the quality and type of calories consumed, and this is both the motivating factor as well as the primary benefit behind the advice to "quit counting calories." Aside from this simple fact, folks who are eating this way tend to consume fewer calories anyway, for a number of reasons: nutrient density lowers caloric intake because it increases satiety; increased fat and protein intake lowers total caloric intake because it increases satiety; intermittent or periodic fasting (which not everyone does, but the community as a whole tends to encourage) very directly lowers total caloric intake (by roughly 10-15%, taken by week).

As far as diabetes research ... frankly, nearly anything not discovered or reconfirmed within the last 15-20 years is garbage. The medical community barely understood what was going on at a macro-level 50-60 years ago, and certainly didn't have the sophistication or capacity to understand the very complex biochemical interactions that occur with normal metabolism, much less diabetic pathology. And the Calorie Restriction Society has a vested survivalist interest in promoting the idea upon which it is founded, in much the same way that the American College of Cardiology has a vested interest in continuing to promote statin usage despite the ever-growing mountains of evidence that they do more harm than good in most patients.

So while it is certainly the case that number of calories has meaning, it just has far less meaning within a population eating in the ways that we tend to, and furthermore tends to confound the process of moving away from SAD and more toward the paleo/primal lifestyle.

I've seen various members of the Calorie Restriction Society in interviews etc. numerous times. No thanks. I'd rather enjoy my life.

As to Taubes, I'll only suggest to everyone reading this that they get their biochemistry and metabolism education from someone who has a good grasp of it themselves, not a science journalist who didn't even read several of his own sources.

How one could eat over 2000 calories on a Paleo diet is beyond me! I was calorie counting and doing Paleo for about a week before giving up as I hadn't managed to eat over 1200 calories. I snack all day, eat two main meals every day and always have dessert.

I am a big fan of Taubes and certainly do not refute him. ditto re the hu-man above me.

Low carb diets of which Paleo is a version are by nature much more calorie regulating than a high grain/processed food [SAD] diet. (he just said that too :) it bears repeating.

I was stunned when for fun i did a typical day food entry for what I was eating prior to my low carb no processed food, no white stuff, hi fat diet (which many call Paleo) I was eating way more calories. On this way of eating I find it very hard to even get to what "authorities" would call my RDI.

Not worrying about/counting calories does not always mean you are eating way more..it can also include a much lower calorie intake.

I do not worry about calories nor do I track them. Most diet tracking plans have them because they still think of a "diet" as calorie restriction and that a calorie is a calorie..-which is not quite so simple.

Paleo and other low carb are ways of eating lifestyles under the broader meaning of diet. He has a diet of fish and lentils (way of eating) . NOT he is on a 1300 cal a day diet (restrictive -way of NOT eating.

When eating a high fat diet, with very calorically dense foods, I eat less calories than I ever have before when I was eating tons of bread and carbs. The question you phrased seems to assume that eating meat and fat will make everyone double their calories or something. I think a lot of people who start off paleo the "proper" way, meaning as an introduction with no "cheating" and with zero processed foods, they will also find that their satiety will improve and will naturally be consuming adequate calories based on their hunger cues (with some exception such as a history of eating disorders). There are also techniques, like leptin reset and IFing that may assist in helping gain back the ability to actually feel full and satisfied after eating.

I don't think we are doing a disservice by telling people to eat when they are hungry and don't worry about calories. Most people have been counting them their whole life and magically gaining and losing weight seemingly independent of their hunger and food intake (for example my BF pre-paleo was eating 3500 calories a day and losing tons of weight, I was eating 1200 and gaining). I think that counting calories as a means of caloric restriction can lead to obsessing over food intake and following the numbers instead of how you feel, which can lead to both ignoring your body and encouraging disordered eating. Eating natural food that we are supposed to eat and knowing when we feel full, is the only way that "caloric restriction" should safely be practiced in the long term.

The correlation studies in the 50's and 60's, I don't think it was a mistake to overlook them. Through research now we know that there is a statistically insignificant difference in most age groups for activity levels between overweight/obese individuals and normal weight individuals, as well as a very slight difference in caloric intake. It's not for wont of trying or will power, and it isn't about individual gluttony or sloth- the whole world didn't wake up and decide to become morally corrupt. I think we can instead thank our food system, and move back towards eating what we are supposed to.

I believe intermittant fasting is supposed to provide many of the same benefits as caloric restriction.

Do the Blue Zone populations intentionally restrict calories? Are they eating according to appetite? My biggest take away from Taubes is that calorie counting is ineffective if it doesn't allow for appetite self-regulation and that is why dietary composition is more important than just counting calories.

the work of Dr Cynthia Kenyon and Dr Luigi Fontana puts forth some compelling arguments in support of chronic calorie restriction

The Biosphere 2 experiment is an interesting read

I am personally violently against counting calories because it's anal and boring. I'd rather pluck my leg hairs out one at a time. However, I am aware of the general calorie content of foods and I tend to limit the super-high calorie ones (nuts, coconut milk, avocado, heavy cream, dark chocolate) if I feel I'm gaining weight. Seems to work as my weight has stabilized within a five-pound range. (But I don't pay a lot of attention to the scale, either...)

SO to answer the OP, I suppose calories do matter in a certain sense. But I don't think counting is necessary or even a good idea. I think it's better to take the ball-park approach, tune into how I feel, how much I'm moving, how hungry I am, what time of the month it is. And adjust accordingly. Much less obsessive.

Just intermittent fast. get all the benefits of CR without any of the drawbacks