Just published:

Ketogenic low-carbohydrate diets have no metabolic advantage over nonketogenic low-carbohydrate diets.

Johnston CS, Tjonn SL, Swan PD, White A, Hutchins H, Sears B.
Am J Clin Nutr. 2006 May;83(5):1055-61. Related Articles, Links
Department of Nutrition, Arizona State University, Mesa, AZ.

BACKGROUND: Low-carbohydrate diets may promote greater weight loss than does the conventional low-fat, high-carbohydrate diet. OBJECTIVE: We compared weight loss and biomarker change in adults adhering to a ketogenic low-carbohydrate (KLC) diet or a nonketogenic low-carbohydrate (NLC) diet. DESIGN: Twenty adults [body mass index (in kg/m(2)): 34.4 +/- 1.0] were randomly assigned to the KLC (60% of energy as fat, beginning with approximately 5% of energy as carbohydrate) or NLC (30% of energy as fat; approximately 40% of energy as carbohydrate) diet. During the 6-wk trial, participants were sedentary, and 24-h intakes were strictly controlled. RESULTS: Mean (+/-SE) weight losses (6.3 +/- 0.6 and 7.2 +/- 0.8 kg in KLC and NLC dieters, respectively; P = 0.324) and fat losses (3.4 and 5.5 kg in KLC and NLC dieters, respectively; P = 0.111) did not differ significantly by group after 6 wk. Blood beta-hydroxybutyrate in the KLC dieters was 3.6 times that in the NLC dieters at week 2 (P = 0.018), and LDL cholesterol was directly correlated with blood beta-hydroxybutyrate (r = 0.297, P = 0.025). Overall, insulin sensitivity and resting energy expenditure increased and serum gamma-glutamyltransferase concentrations decreased in both diet groups during the 6-wk trial (P < 0.05). However, inflammatory risk (arachidonic acid:eicosapentaenoic acid ratios in plasma phospholipids) and perceptions of vigor were more adversely affected by the KLC than by the NLC diet. CONCLUSIONS: KLC and NLC diets were equally effective in reducing body weight and insulin resistance, but the KLC diet was associated with several adverse metabolic and emotional effects. The use of ketogenic diets for weight loss is not warranted.

PMID: 16685046 [PubMed - in process]

It was a 6 week study. I doubt those on the ketogenic diet had had time to become fully adapted to it.

I think this study will be widely quoted as it "proves" low carb diets are NOT HEALTHY!

Michelle

Hmmm, sounds like something Barry Sears (The Omega Rx Zone)would say. Wonder if that's him at the end of the author list? 40% carbs is about what the Zone recommends I think.

Despite that, this is pretty interesting stuff. Maybe it explains why my TC and LDL keep going up, even though my HDL is great and my cardio-CRP is almost unmeasurable.

I just read this. Here's the link. Almost makes it worth buying a subscription to AJCN to read the whole thing.


http://www.ncbi.nlm.nih.gov/entrez/...l=pubmed_docsum

I hadn't noticed that before - but I think you're right. The next time I'm at the UW medical library I'm going to pull the PDF of this article and look at study design and whole paper. Obviously, it showed the results that he wanted.
The abstract also doesn't quantify the "adverse emotional impact" of a ketogenic diet.

So basically they compared 2 sets of relatively healthy, overweight people and found that very low carb vs reduced carb was of no benefit. That's such a flawed study and retarded conclusion. It's like taking 20 normal people and randomly casting half their legs and the other half bandaging them... and then concluding the casting isn't important because both groups legs worked relatively the same at the end of the study. DUH.

I know for a fact, to my body, 40% carbs and 30% fat isn't going to cut it. This is actually a little lower than what I was eating to carb up when I was going to test my sugar (I was eating 50% carbs and 35% fats I think). I was having hypoglycemic crashes after every meal. It was simply *impossible* for me to keep my sugar stable without submitting to eat a lot of food (during that experiment I gained logical understanding into why all uncontrolled reactive hypoglycemics must also be overweight; if you eat carbs it is simply not mathetmatically possible to eat a normal amount of food, calorie wise, while also keeping your sugar out of the red most of the day).

If 40% carbs is not sufficient to keep my insulin/glucagon balanced (prevent hypos), that automatically means it is not sufficient to keep my metabolism as high as it should be (insulin will be suppressing lipolysis and gluconeogenesis, creating energy pits experienced as lethargy and/or sugar crashes, thus suppressing metabolic rate). Therefore I know for a fact 40% carbs, to my body, does not allow for nearly as high a metabolic rate or energy state as much lower.

Get 20 hypoglycemics, 20 diabetics, 20 people with elevated insulin levels, 20 people with insulin resistance syndrome... THEN let's see whether or not 30% fats/40% carbs works as well as much lower and 60% fats/5% carb.

So essentially they were comparing people on induction with people on OWL?

First off 20 subjects is not enough for a valid randomized study.

Humm ... "5% of energy as carbohydrate." I wonder how many grams/day that is and what was it?

"During the 6-wk trial, participants were sedentary, and 24-h intakes were strictly controlled." How, were they in prison? A cheat on LC has way more impact than a cheat on higher carb.

I wonder who funded this one-- the sugar institute?

Yeah, at the least it reinforce the mainstream medical opinion that ketosis is bad and even dangerous.

I think they should have included a control group, and at least 10 people on a low-fat diet.

I think it's just Barry Sears, trying to prove that the Zone diet is better for you than Atkins.

I think it is almost like comparing Induction to South Beach!

The Zone had an "adverse emotional impact" on me - I was starving all the time and constantly thinking about food and how to balance blocks at my next meal!

We're all experiments of one. I was on the Zone Diet when it was first published. (Long before anyone heard of Atkins) I lost weight but got bored with trying to make every meal a balanced protein/carb. I'm back on it and losing weight again. I think part of the problem the first time was not having enough fat in the diet.

The Zone's basis theory is that eating every meal with a ratio of 0.7 protein too 1.0 carb suppresses insulin. Fat is considered inert because it doesn't affect insulin. Because the protein intake is linked to activity level, you aren't eating a huge amount. By balancing protein with carb my breakfast totaled around 300 calories. Lunch and dinner are similar amount. With two snacks added the total calorie intake per day is 1200 calories.

The stupid cat walked across my keyboard and stepped on the "Send" key before I was done. The point for me is that I'm not hungry on 1200 calories per day. I think it's because of insulin suppression.

On the Atkins diet I lost weight. The metabolic advantage made it easy to gorge myself. On the Zone I need a little bit more discipline. When I was on the Zone the first time my cholesterol was 160. When I switched to Atkins my cholesterol went to 230.

Right now my weight is 170 pounds. The Zone calculations puts my body fat at 16%. I never did that well on Atkins. Like I said, we're all experiments of one.

Fat is inert, but it is not totally neutral ("just calories"). Fat has a profound role in regulating the metabolism. It provides a ready catalyst for lipolysis, which can suppress a body's tendency to make too much of its own sugar (which, I theorize, may be a reason people who are closer to the diabetic side of things find weight loss actually increases when they take oils). It delays gastric emptying, which balances metabolism by slowing the rate sugars enter the blood and satisfying hunger, thus decreasing future eating (and eating augments sugar itself).

I think the zone is a great low carb diet for a very active person, or an average person with a pretty good carb tolerance (that is the sort of person who can eat anything and feel pretty much the same). The ratio of .7 to 1 would never work for me or probably most carb sensitive people. I wish all I had to do was eat 14 g of protein to let me handle 20g carbs. Heh. I can't even eat a meal with 20 carbs and expect to feel top notch no matter what's in it. If it's things like fruits and berries and other low glycemic stuff I can handle a bit more, but rarely can I eat a 20 carb meal and feel good.
Also, it's way more than some simple formula of pro:carb. Fat is extremely important in dictating how much carb I can handle (as is vinegar but that's another issue ). Fat (and vinegar) slow how fast the stomach empties, which greatly reduces how much insulin my body makes as well as my perception of hunger.

[QUOTE=ItsTheWooo]Fat is inert, but it is not totally neutral ("just calories"). Fat has a profound role in regulating the metabolism. It provides a ready catalyst for lipolysis, which can suppress a body's tendency to make too much of its own sugar (which, I theorize, may be a reason people who are closer to the diabetic side of things find weight loss actually increases when they take oils). It delays gastric emptying, which balances metabolism by slowing the rate sugars enter the blood and satisfying hunger, thus decreasing future eating (and eating augments sugar itself).

It's why I think the Zone failed for me the first time. I stuck with lean meats and ate little fat. I see that fat in the diet stimulates lipolysis, especially if there isn't a large amount of ready carb. But by Sears version, it's that protein/carb ratio that suppresses insulin, not the fat. Fat has no effect on eicosanoids, the real reason for the Zone's purported health benefits.