Comment by SoftwareMaven | Hacker News Reader

Comment by SoftwareMaven | Hacker News Reader

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Hmm, tough question. Here are some of the studies that struck me most. The danger of something like this is it can look like confirmation bias; that is not the case. It just happens that a close, impartial reading of the evidence tends to lean one direction.

* Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women[1]

* Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance[2]

* The ketogenic diet as a treatment paradigm for diverse neurological disorders[3]

* The ketogenic diet reverses gene expression patterns and reduces reactive oxygen species levels when used as an adjuvant therapy for glioma[4]

* A Systematic Review of the Evidence Supporting a Causal Link Between Dietary Factors and Coronary Heart Disease[5]

At the time, I wrote a wikia article[6] that tried to distil all of my thoughts and what I had learned. It is mostly correct, but I'm sure I got some things wrong. I haven't gone back over it in some time.

More recently, I think this article (Dietary Carbohydrate restriction as the first approach in diabetes management. Critical review and evidence base)[7] gives a good overview of the metabolic benefits.

All of this does not imply that I think a ketogenic diet is the One and True Path(tm); it is far more nuanced than that, but that's not a bad place to start for a lot of people.

1. http://www.mwc.com.br/files/Gardner_-_Standford_A_to_Z.pdf

2. http://jama.jamanetwork.com/article.aspx?articleid=1199154

3. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3321471/pdf/fpha...

4. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2949862/

5. http://archinte.jamanetwork.com/article.aspx?articleid=11084...

6. http://fat-head.wikia.com/wiki/Health_Benefits_of_a_Low_Carb...

7. http://www.nutritionjrnl.com/article/S0899-9007(14)00332-3/f...

This is good info, the only things I would add here:

* carbohydrate intake should really depend on your activity level. I'm guessing the majority of the people in these studies were sedentary so a ketogenic diet is a pretty good option. People who are more active should consume some carbohydrates because glycogen depletion tends to mess with energy levels.

* A higher dietary protein intake has been shown to increase satiety and lead to weight loss by itself. Regardless of your diet you should increase your intake of high protein foods; beans and low fat cultured dairy are good sources.

Steve Phinney and Jeff Volek have done a lot of research into high performance athletes using a ketogenic diet (see, for instance, The Art and Science of Low Carbohydrate Performance[1]). Extreme endurance athletes are using ketogenic diets as a tool to smash records in ultramarathon running[2].

Nobody needs carbohydrate. That doesn't mean carbs are necessarily bad, but the long-time trope that you have to have them if you want to move further than your couch is just silly and has long been disproven (if, by nobody else, hunter-gatherers who had gone days without food while running down a kill).

Phinney and Volek have found interesting things about fat and high-intensity exercise:

* Fat utilization in keto-adapted individuals that is, literally, re-writing textbooks. Levels of fat mobilization that have never been seen in laboratories is being recorded. This likely has a genetic component, what I would consider the opposite of the multiple copies of the amylase gene that highly carb-tolerant people seem to have.

* Fat requires less oxygen to utilize, leading to less lactic acid, less muscle tissue damage, and faster recovery.

* Keto-adapted athletes are much more efficient in their use of their glycogen stores, using less when passing 70% VO2-max and replenishing supplies faster. They do not store as much glycogen as carb-burners, so the net effect winds up being about the same amount of power from glycogen between carb and fat burners.

That doesn't mean there are no athletes who would see benefits of carbs, but, in a fat-adapted state, those carbs can be much, much more strategic in nature (the cyclist sprinting over the hill, the olympic lifter in competition, etc). Peter Attia talks a lot about his strategic use of carbs while exercising[3].

Personally, I see beans as a food to be very cautious with. The phytates, lectins, and saponins in them are there to protect the seed, since plants can't run away to protect their offspring. They use chemical warfare, and are quite good at it, leading to poor absorption of nutrients[4]. Properly preparing them (soaking and fermenting) can address this problem, something done in all societies previous to the 20th century, but rarely done now.

I also can't see any reason to use low fat, well, anything. Fat is a perfectly healthy macronutrient, and, when going for low fat, you are typically getting a lot of sugar and additives put in to replace the taste and texture of the lost fat. On the other hand, live-cultured dairy products, for those who can tolerate lactose, are an amazing food.

1. http://www.artandscienceoflowcarb.com/the-art-and-science-of...

2. http://www.meandmydiabetes.com/2012/08/11/western-states-100...

3. http://eatingacademy.com

4. http://ajcn.nutrition.org/content/49/1/140.short

Thanks! This plays nicely with my confirmation bias; I've been on a ketogenic diet since March and I've felt much better because of it.

+1 ketogenic...in fact for me, lost 100lb on ketogenic, then slowly added back carbs (increasing exercise) gained back 20lb. went back on ketogenic, isocaloric and less exercise...immediately dropped back down

Carbs soak up water, so it's natural that you would gain weight when adding carbs and lose weight when you remove them. That's why doctors and nutritionists say not to worry about your weight, but worry about your waist. Weight can be misleading.

The amount of carbs stored in the human body would not account for 100 lbs, not even for 20 lbs. A couple of pounds of carbs are stored in the body, in the form of glycogen, plus the water it soaks - maybe three times more, so the difference may be about 8, maximum 10 pounds.

I would certainly worry about 20 lbs gain, carbs or no carbs.

WATER not carbs. It's a well known effect.

Yes. The only way the carbs are stored in the human body is in the form of glycogen, in liver and skeletal muscle. There's about 1 kg of it in total, maybe a bit more if you're a trained athlete. And glycogen binds about, maybe, up to 3 times as much water by weight. So, altogether, about 4 kg.

After switching to keto, glycogen is used up gradually, due to no carbs entering the body. And the water is also lost. Therefore, the "signing bonus" of the keto diet - a significant weight loss in the beginning, but due to water lost, not fat burned.

BUT. That only accounts for about 4 kilos, maybe just a bit more. You can't really blame water for a gain of 20 pounds.

Am I missing something?

No one ever said it could account for 20 lbs. Merely that you should expect weight loss when you're cutting carbs and weight gain when you reintroduce carbs.

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