Macronutrients and Weight Loss


Here’s a new study looking at the correlation between carbohydrate consumption and obesity: “Macronutrients and Obesity: Revisiting the Calories in, Calories out Framework.” The study looked at how changes in the amount of calories coming from carbs from 1974-2006 in the US and in various other countries in the last decade correlate with obesity levels. Basically, the more calories people get from carbs, the fatter they get. This tends to be because when people eat more carbs, they eat more calories.

This seems consistent with other research. The A to Z Diet Study showed more weight loss with people on a high-fat diet than with other alternatives. This study on weight maintenance also showed better weight maintenance on a high-fat diet than with a high carb diets. I’m not aware of any contrary research on this. The general consensus is that high-fat diets tend to be better for appetite management, which is the bedrock for any successful diet that we weak-willed, flesh-and-blood humans might try to stick to.

That being said, even if high-fat diets are better for weight loss, whether it’s healthier overall is a whole separate and much more controversial question.


What kind of macro breakdown are we talking about here? I’ve been using 40% carb/20% protein/40% fat lately. The protein is already higher than the recommended intake for my body mass/activity level. Do I just substitute more fat for the carbs?


I think with low carbing, you should be somewhat limiting protein (not low protein, but not high). This is because excess protein will be converted to glucose via gluconeogenesis, so a high protein version of low carb would just hinder the adaptation to fat burning (or so the theory goes, I cannot vouch for its validity ;)). (apologies if you already know this :))

This more applies to going towards very low carb however (and into the mysterious and exciting realms of keto). I would think 20-30% protein is about where you would want to be, so I don’t think you need to reduce any more. Once your protein is set yeh, its just a straight switch between carb / fat depending on how low carb you fancy :slight_smile:

Are you looking to dabble with keto, or just moderate low carb?


I’m not really interested in a ‘keto’ diet, as I don’t want to be a diet weirdo who wont share meals with friends or have a slice of birthday cake. I just tried to research good/reasonable macro breakdowns, and all I found were recommendations for bodybuilding and then some suspicious new age stuff about high fat/high protein diets. I just want a reasonable balance of macronutrients not inconsistent with good heatlh. I started with a bit higher carbs than fat, but went for equal amounts a bit later. I hope 225g of carbs is not too unreasonable. There seems to be little good information about healthful macro amounts without delving into ‘fad diet’ territory.


This is all old news. Or rather, old, and yet not yet publicly accepted news despite overwhelming evidence. Takes a while for momentum to build when it involves such a large shift. I suggest you read Why We Get Fat: And What to Do About It. Then, if you want to delve into the scientific rigor, follow the book’s citations of all of the studies it references to the original material. (FYI I lost 20 pounds in ~3 months on a carbohydrate restricted diet, no exercise, one of the easiest things I’ve ever done, and now I’m at ~10% body fat.)

Gary Taubes is a researcher. I’d say the two leading physicians in low carbohydrate diets are Jeff Volek and Stephen Phinney and their books are The Art and Science of Low Carbohydrate Living and The Art and Science of Low Carbohydate Performance. I cleansed these urls of any Amazon referrals.

In my opinion any appropriately skeptical investigation would find the data clear-cut and overwhelming and there would be hardly any controversy at all, but there are few willing to examine the data because they suspect it to be some sort of pseudo-science since it’s so opposite of ubiquitous “low fat” dieting trends… as obesity continues its upward trend.