Read food labels. It helps the paleo person avoid bad fats, sugars, etc.

To echo the answers of others, I do think calories count. I eat to satisfaction at lunch and dinner (100% Paleo) and eat breakfast when I'm hungry. I was losing weight, but with frustrating plateaus.

I'm a life-long milk LOVER, and switched to drinking one cup or so of heavy cream per day. When I stopped that I stopped plateauing on weight loss.

Sure, heavy cream is not a carby food - but it is still well over 700 calories I believe. That is a LOT of unnecessary!

I don't count calories, but I have cut back on doing stuff like that. I also limit my pre-bedtime snacks to a tablespoon or so of coconut milk or I wake up hungry during the night.

The saying "eat like a king at breakfast, a prince at lunch and a pauper at dinner" still seems relevant to me, even though I don't always follow the conventional meal structure of three squares a day. Broadly interpreted it dovetails neatly with the science on IF, sleep quality and HGH release, and also fits with my own food bio-rhythm. I find that night eating triggers the desire to binge on Paleo foods and anything larger than a moderately sized lunch (regardless of macronutrient composition) makes me drowsy and inattentive.

Also, at the risk of coming across as an unbearable pedant, conventional wisdom actually embraced smoking for many years - doctors would even encourage pregnant women to take up smoking for the sake of their nerves! If only in a few years time people would report advice about wholegrain consumption with similar incredulity.

It is relatively recent, but CW now vilifies transfat and added sugar / HFCS more than anything else now. Beats the previous saturated fat thing (and some mainstream medical colleges are saying that maybe sat fat is not so bad now....).

Calories count for me when they are carb calories. But it is impossible for me to say how much calories count when they are fat (in the absence of excess carb) or protein, because those macronutrients also provide for structural and biochemical needs. While calorie theorists talk about BMR and take that into account, it covers energy needs only. There is no BMR equivalent for lean tissue maintenance, hormone production, etc., yet those things come from food.

Basically, we're not bomb calorimeters. Food is not just fuel, it's also spare parts.

I throw the term "conventional wisdom" around but I don't like it much; I use it because other people understand what I'm talking about. It's a sort of rhetorical shorthand. But wisdom is not a majority vote. It comes only from experience. When you have a bunch of people sitting around guessing about something without fully testing their ideas, that's not wisdom, it's B.S.ing.

(edit) To provide another angle to what someone else said here: Don't just do something because an ancestor might have done it. Do things that an ancestral group did that allowed the group to exist a long time in relatively good health (not counting infectious disease or accidents--and you can even learn from those experiences). If all your ancestors worked themselves to the bone as serfs in the fields of a feudal lord and none of them lived past thirty, well, you know you don't want to emulate that. But if the people in your ancestral group who survived infant mortality, infections, and accidents lived to be sixty or better, you are probably on the right track, assuming you live in the same area they did.

Context is everything, it would seem.

I have to agree with both of your answers: I think calories do matter, and I find that food journaling is (so far) the only way I have successfully achieved lasting weight loss. I also find that reduced sodium intake makes me feel better, just as CW would have us believe.

In other areas, there are plenty of ways that CW is correct in protecting my health - for instance, I always wear seatbelts, and I think that defensive drivers are safer than aggressive drivers. However, to stay in the same general area, studies have shown that booster seats (and many kinds of car seats) do not significantly improve the safety of children (not infants) when compared to regular seatbelts.

I think in nutrition, as well as safety and other aspects of life, the important part is to remember that scientific evidence should always trump anecdotal evidence – I’m not interested in Paleo BECAUSE our ancestors did it. I’m interested because there is scientific evidence that shows this lifestyle improves health and wellness.

For me - and a few other PaleoHackers I know, as well - food journaling has turned out so far to be instrumental in kickstarting and maintaining weight loss. I don't even food journal for calorie restriction; actually I eat plus-or-minus 2200 calories/day (though I'm nursing, so that makes a difference) and around 70% fat, 20% protein, 10% carbs. I cite food journaling as CW being right because it is quite frequently recommended by mainstream media dieticians, etc., but many paleo proponents insist that it is unnecessary as you should eat until full. Unfortunately for me I'm still trying to recalibrate what it actually means to be full, so for now the journaling is giving me a realistic base.

Central to my journaling though is discovering my actual carb intake, which has been great for me in terms of monitoring (along with ketostix) when I'm in - and how to stay in - ketosis.

I don't know if it's a long term habit for me, but for now it keeps me on track for my weight loss goals - and as long as that's working I'll be doing it!