Low-carb diet wins, losers cry foul
The paper that the London Times wrote about last week finally saw publication today in the Journal of the American Medical Association (JAMA). The study showed that a low-carb diet, followed for a year, produced vastly superior weight loss in premenopausal women as compared to a handful of low-fat diets. As might be expected, the promoters of the low-fat diets are crying foul.
The study is pretty straightforward. 311 overweight, premenopausal women were recruited by researchers at Stanford University and randomized into one of four dietary regimens: the Atkins diet, the Zone diet, the LEARN diet or the Ornish diet. After randomization into a specific diet the women received literature and weekly instruction for two months. Researchers obtained blood work, weight and measurements of the subjects at the start of the study and at 2 month, 6 month and 12 month intervals. At the end of the study, those subjects on the Atkins diet lost substantially more weight than subjects on the other three regimens and had either equal or better metabolic findings.
This study is pretty interesting for a couple of reasons. First, the participants were given the books and literature of the various regimes.
Participants were assigned 1 of 4 diet books: Dr Atkins’ New Diet Revolution, Enter the Zone, The LEARNManual for Weight Management, Eat More, Weigh Less by Ornish.
And the one month instruction involved weekly one hour meetings in which the various books were read and studied.
Each diet group attended 1-hour classes led by a registered dietitian once per week for 8 weeks and covered approximately one eighth of their respective books per class. The same dietitian taught all classes to all groups in all 4 cohorts and was rated by participants at the end of the 8-week sessions for enthusiasm and knowledge of the material (rating scale of 1-5, from “strongly disagree” to “strongly agree,” respectively). The LEARN program is intended to be a 16-week program and, therefore, the 8 weeks of guidance through this book reflected an accelerated time frame, which was necessary to match the time frame given for the other 3 diet groups. Efforts to maximize retention in the study included e-mail and telephone reminders for appointments, e-mail or telephone contact from staff between the 2- and 6-month and between the 6- and 12-month data collection points, and incentive payments of $25, $50, and $75 for completing the 2-, 6-, and 12-month data collection, respectively.
The two month instruction period ensured that participants at least read (or had read to them) the book that promoted the particular regimen they were following. Although the participants rated the instructor the same (4.7 out of 5), I can’t imagine that there wasn’t some variation in enthusiasm for a particular program. The same instructor gave instruction to all the groups. How can you get enthusiastic about recommending the Atkins diet then turn around and be just as fired up about hyping Ornish? Or vice versa? I couldn’t do it.
Let’s take a look at what the participants went through in their weekly instruction.
Each group received specific target goals according to the emphasis of the assigned diet. The Atkins group aimed for 20 g/d or less of carbohydrate for “induction” (usually 2-3 months) and 50 g/d or less of carbohydrate for the subsequent “ongoing weight loss” phase. The Zone group’s primary emphasis was a 40%-30%-30% distribution of carbohydrate, protein, and fat, respectively. The LEARN group was instructed to follow a prudent diet that included 55% to 60% energy from carbohydrate and less than 10% energy from saturated fat, caloric restriction, increased exercise, and behavior modification strategies. The primary emphasis for the Ornish group was no more than 10% of energy from fat. Additional recommendations given for physical activity, nutritional supplements, and behavioral strategies were consistent with those presented in each diet book.The guidelines for the Zone and LEARN diets incorporated specific goals for energy restriction, while for the Atkins and Ornish diets, there were no specific energy restriction goals.
So, the subjects were randomized into the various diets, which is important because were they allowed to self-select each would have gravitated to a diet most in sync with his (or her) nutritional beliefs. (Putting someone who would prefer Atkins into the Ornish group and vice versa gives a little more validity to the dropout figures, which, as we’ll see, are enlightening.) And the subjects were given pretty intensive instruction in the particular dietary promoter’s regimen. Not just a generic low-fat diet, for example, but the Ornish low-fat diet as presented by Ornish himself in his own book.
So what happened?
Well, this little graph pretty much says it all.
As you can see, in terms of weight loss the Atkins diet won hands down. The other three contenders were clustered together at a distant second.
Let’s take a look the what the people following the various diets ate in terms of calories and carbs.
If you do the calculations as I did you discover that at the two month mark the subjects on the Atkins diet are eating an average of 1381 kcal per day, 61 grams of which are carbohydrate. The calories and carbs climb throughout the year so that by the end of the study period the Atkins dieters are eating 1599 kcal per day, 140 grams of which are carbohydrate. These carbohydrate figures don’t really fit with the Atkins’ recommendation to restrict carbs to 20 grams per day (the induction phase) for 2-3 months. Were carbs restricted to Atkins levels they would have represented about 5-6 percent of intake instead of the 18-35 percent that it actually turned out.
MD and I are always asked (in fact, she got three emails today alone asking) what is the difference between our diet and the Atkins diet. One of the differences is that we have a different way of counting carbs that allows a more total carb than Atkins, but still provides the same weight loss and metabolic improvement benefits. We discovered by trial and error with ourselves and thousands of patients that insulin can be lowered just fine without the drastic carb restriction the Atkins diet as described in his book demands. In fact the people in this study – although schooled for two months from the Atkins book – were actually on a Protein Power diet, at least for the first two months. (Someday I’ll post on the relationship I had with Atkins and my annoyance that every incarnation of a low-carb diet is referred to as the Atkins diet.)
Here is the complete Table showing the intake of all the macronutrients.
I could drone on forever about all the interesting findings that can be plucked from just this one table, but let me leave you with just two. First, take a look at the fiber intake. I don’t really care about fiber because it’s been shown to be pretty much worthless as any kind of a healthful thing, but others haven’t read all the medical literature yet and so continue to think it’s wonderful. Look at the highest of the high carb diets, the Ornish diet, and notice that there just ain’t that much more fiber than on the Atkins diet. None of the diets has the recommended 25 grams per day. And look at the saturated fat intake. The Atkins diet followers ate a little over 15 percent of their calories as saturated fat (50% more than the recomended 10%), yet they had no increase in LDL. (See chart below). Once again proving that there is really no correlation between saturated fat intake and LDL levels. Finally, I found it interesting that twice as many subjects dropped out of the Zone, Ornish, LEARN diets than did from the Atkins.
The authors of this study drilled down pretty deeply into the lipid levels as a function of fat, especially saturated fat, in the diet.
Many concerns have been expressed that low-carbohydrate weight-loss diets, high in total and saturated fat, will adversely affect blood lipid levels and cardiovascular risk. These concerns have not been substantiated in recent weight-loss diet trials. The recent trials, like the current study, have consistently reported that triglycerides, HDL-C, blood pressure, and measures of insulin resistance either were not significantly different or were more favorable for the very-low-carbohydrate groups. [My italics]
The exception to this pattern has been LDL-C concentrations. Two of the most consistent findings in recent trials of low-carbohydrate vs low-fat diets have been higher LDL-C concentrations and lower triglyceride concentrations in the low-carbohydrate diets. Although a higher LDL-C concentration would appear to be an adverse effect, this may not be the case under these study conditions. The triglyceride-lowering effect of a low-carbohydrate diet leads to an increase in LDL particle size, which is known to decrease LDL atherogenicity. In the current study, at 2 months, mean LDL-C concentrations increased by 2% and mean triglyceride concentrations decreased by 30% in the Atkins group. These findings are consistent with a beneficial increase in LDL particle size, although LDL particle size was not assessed in our study. In addition, we examined non–HDL-C concentrations as an alternate indicator of atherogenic lipoproteins—a variable not substantially influenced by changes in triglyceride concentrations—and observed no significant differences among groups at any time point.
Therefore, we interpret these findings to suggest that there were no adverse effects on the lipid variables for women following the Atkins diet compared with the other diets and, furthermore, no adverse effects were observed on any weight-related variable measured in this study at any time point for the Atkins group. Further examination of the dietary effects on lipid variables would benefit from analyses of lipoprotein particle subfractions and follow-up of longer than 12 months.
Here is the chart of the blood and anthropomorphic findings with all the diets. (I cropped the notes so that the table would fit the page better.)
You can pretty much cruise through these charts and tables yourself and get the gist of the study. The low-carb diet preformed magnificently, as it typically does. Subjects following the low-carb diet lost more weight and had improvement, or at the very least, no change, in all other parameters measured. It was pretty much a grand slam no matter how you count it.
What I have found wonderfully amusing are the anguished cries from those promoters whose diets were savaged in this comparison study. Remember, as you read their comments, that the subjects followed the promoters diets as laid out by the promoters. The subjects on the Dean Ornish diet learned from Dr. Ornish’s book. If they didn’t follow it correctly, who’s fault it that?
From David Katz, who is involved with the LEARN program:
“You lose weight if you have cholera, too,” said Dr. David Katz, director and co-founder of the Yale Prevention Research Center and a longtime critic of the Atkins diet. “You can’t measure overall health by a few cardiac risk factors.” [Is this the same David Katz who says we all need to take statins to lower our cholesterol levels?]
“It’s flawed,” Katz said. [Oh, really? Mind telling me how?]
“Nothing in this study will change nutritional recommendations I make to my patients,” Katz said. [Nothing like an open minded scientist.]
Katz argues that given everything researchers know about food, the debate over the best types of nutrition should be over. People need fresh fruits and vegetables and should stay away from saturated fats and junk food, he said.
He also noted the relatively small amount of weight loss among the women in the study as proof that people need to be exposed to healthy foods at an early age before they gain weight.
“It is sad,” Katz said. “It points out the importance of our overall food environment,” he said.
From Barry Sears:
Barry Sears, creator of the Zone diet, defended his approach to weight loss despite Zone’s fourth place showing in the JAMA study.
He blamed the result on the fact that subjects on his diet in the study group actually ate more carbohydrates and less protein than he recommends in his plan.
The percentage of carbohydrates, proteins and fats subjects consumed in the Atkins group more closely resemble his own recommendation that dieters consume about 40 percent of the calories they take in as carbohydrates, 30 percent in fat and 30 percent in protein. [Go back and look at the charts, Barry]
“I like the term moderation,” Sears said.
The study ”had a good concept and incredibly pathetic execution
And from Dean Ornish:
A new comparison of four diets—including mine—is misleading and riddled with problems.
…many people may go on a diet that harms them based on inaccurate information.
Most study participants weren’t following an Ornish diet, which is 10 percent fat. They reduced their fat intake from an average of 35 percent to only 30 percent after one year. If they’re not following the dietary recommendations, it’s not surprising that they didn’t show as much improvement. By analogy, two thirds of people prescribed Lipitor aren’t taking it only four months later. Lipitor is a very effective way to lower cholesterol levels, but only if you take it. It would have been helpful if the authors had reported findings on the subset of people who actually followed the different diets to see what happened to them.
Dr. Ornish then prattles on about how those who really stick to his diet really do well. Really, they do. It’s tougher to stick to the Ornish diet than it is to discover the father of Anna Nicole Smith’s baby.
As you might imagine, this study won’t put an end to the great diet debate. But those of us who are old hands at the low-carb diet know the answer. It’ll just take the rest of the world a little longer to figure it out.
Yes, the idiocy is astounding. Even a little bit of critical thinking reveals why Ornish, LEARN, etc. are tough to stick with compared with Protein Power/Atkins/Paleo etc. The bozo “experts” are stuck in the mindset that somehow modern science can cook up a better recipe for health than millions of years of evolution. Remember the whole infant formula vs. breast milk debacle?
When viewed in the light of evolution, it’s such a no-brainer, I wonder if even Ornish could find a way around the obvious conclusions (probably, given his idiocy about HDL, and so forth). In nature, foods taste good to organisms because they contain nutrients required for good health. Similarly, cravings are the body’s way of telling you that you’re running short on something it needs. Fat is an essential nutrient, so it’s no surprise it’s so difficult to stick to 10% of calories. Ornish and the rest of his Puritanical ilk would have us believe that the desire for tasty and satisfying food is akin to a mortal sin.
The real issue here (no surprise to followers of Protein Power) is one of manipulating natural impulses through food processing. Take away any significant processing, beyond harvest, kill, clean, and cook, and what’s left? Sugar, grains, and vegetable oils go bye-bye, taking with them almost every boxed food in the grocery store. Stick with locally available food, and you’ve got meat, leafy and root veggies, and fruit when in season.
It’s no surprise it’s easiest to stick with this diet, because it gives you the nutrients your body evolved to require. Instead of having to fight against several million years of evolutionarily ingrained biochemistry, you need only resist the psychological temptations of industrially manipulated foods. Not that that is easy either, but definitely easier than battling deep survival instincts.
I love watching people’s faces when I lay this argument on them. After all, who ultimately has more credibility: Dean Ornish or Mother Nature? The usual expression is one of complete cognitive dissonance, much like that of Nigel Tufnel in “Spinal Tap” when asked why he didn’t just make 10 the loudest setting on his amplifier. After a long glassy-eyed pause, the best he could muster was “This one goes to 11.”
That’s about all Dean Ornish seems to be able to come up with as well.
Hi Dave–
Thanks for the great comment!
Best–
MRE
I will agree with you that the zone requires a different kind of character. I suppose I forget that in my environment (athletics) that precision (obsessive compulsiveness) is somewhat of a necessity for success.
You’re also right that people tend to sway toward the path of least resistance “hence the bagel” or Zone friendly cake! This is one of the reasons I read this blog, you and your wife are always harping about food quality, nutrient density etc, etc…
You have to admit though that while the means may have been different the best results were as prescribed. Perhaps thats the issue its not a problem with the prescription perse, but an issue with the delivery system which is what leads me to argue that the results are still somewhat flawed.
If you prescribed a drug to a patient and they didn’t understand the instructions, they ate the whole bottle and died, is the precription at fault or the patient? I’d say the patient, so what if its complicated but the results of a study on prescriptions must show the results of the prescriptions not the results of what people did with the prescription.
Do this study, 3 groups, 250 people per group:
Group 1 – is Rx’d 0.5mg of Morphine/Day, but given a 1000mg bottle.
Group 2 – is Rx’d 10mg of T3/day, given a 1000mg bottle.
Group 3 – is Rd’d 25mg of Ibuprofen/day, given 25mg dose/day.
Here’s my bet:
Group 1
- 85 are addicted to Morphine within 1 month and suffering from hallucinations.
- 82 are selling large portions of their presciptions
- 83 are taking their presciptions as Rx’d (might be overeaching here;)
Group 2
- 175 are selling their prescriptions
- 25 have died from mixing with alcohol
- 50 are taking as Rx’d
Group 3
- 248 are taking it as is forced upon them!
- 2 have allergies
HEADLINES:
Morphine and T3 proven to be addictive, deadly and lead to unlawful behavior in 75% of prescriptions.
Ibuprofen proven to be safe 99% of the time.
Its not that the prescriptions were faulty its that the delivery system was faulty. The people taking the prescriptions were flawed. Tis the problem when dealing with people. They are people and they are going to screw it up unless it is forced upon them. So saying that one diet is better than another in terms of fat loss is only part of the question. The other question is how many people actually followed the diet?
Find those who did then crunch the numbers again… The zone being for anal people not withstanding of course which I agree with!
These studies should be done on inmates who have no choice but to eat what is provided.
Does that make sense at all? I’m sure you understand what I’m saying better than I do
Hi Pierre–
Re: your analogy. If I gave someone a bottle of prescription medicine with the instructions clearly printed on the bottle, then spent 8 weeks going over exactly what the instructions said, I would figure that the patients would be able to follow the instructions to the letter. But if they didn’t and instead took the medications incorrectly, I would have to conclude that there is something wrong with the instructions. Or the patients are complete morons.
My point is that this study was done using diet books that are available to anyone. It shows what kind of results people can get following those diet books to the best of their ability. In the case of this study, the Atkins diet won hands down. Several conclusions can be drawn from this fact. Maybe the Atkins book is written much more clearly than the others. Maybe people reading the Atkins book are more inspired to follow the instructions because of the way the book is written. Or (and I think this is the case) when people follow a low-carb diet in a half-assed fashion they get a lot better results than they do if they follow the Zone, Ornish or the LEARN program in a half-assed fashion. And since the truth of the matter is that most people who buy diet books probably follow the diet contained therein in a half-assed fashion, then it would seem that the best odds for success would be with a low-carb diet book.
Cheers–
MRE
On that note I like Dave’s comment better than mine!
Dr. Mike,
I think your response to Paul B. really nailed it. A low carb diet is pretty easy to stay on if you believe it will work. My father tried for a few weeks and was skeptical of it but he lost some weight and felt better. His lack of faith however moved him right back into the welcoming arms of Weight Watchers.
In the end, it appears all the diets were tough to stick to and that should speak volumes to the state of our food supply. It is killing us. Mix in a little marketing and bad science/reporting and it is a miracle we live past our 20′s.
Hi Dave–
Too bad about your dad and Weight Watchers.
Keep working on him.
MRE
Don’t mind me Dr. Eades…the post was great, but I want to comment to Fred!
Which leads me to the next point – the Atkins women in this study regained the weight they lost at 6 months in 6 months by eating only ~70 calories more (in the end) and NOT increasing their % of cals by carbs. I find this curious. 70 calories! That’s the cream in your 2 cups of coffee!
This study seems to be screaming out that calories matter – a lot.
Or protein matters a lot more than anyone is looking at. I’m still dredging data from other studies to write about it, but it’s curious that as protein intake peaked (96g – up from habitual baseline of 78g) their weight loss was stong. With each tick downward for protein (6mo down to 86g; 12mo down to 82g) they lost their ability to continue weight loss (with little calories added as you noted)….interesting too is that with each tick down of protein, fat followed back to pretty much their baseline level of consumption (76g baseline; 2mo 84g; 6mo 80g; 12mo 79g).
Then go look at the other plans – their protein and fat we’re going in the exact opposite direction (Zone initially increased) – but with the exception of Ornish, they were also increasing carbs and calories.
Then, if you have a chance, go take a gander at Simpson et al “Protein Leverage Hypothesis” published in 2005 (and ignored)…really interesting read.
There’s something I think we’re all missing….and I have a hunch it’s the protein intake is what is really going to matter most…now I just have to find the time to flesh out the data from enough studies to see if it’s true!
Hi Regina–
Jump on in. I, too, have read the “Protein Leverage Hypothesis” by Simpson and actually have several slides on his work (from this paper and one other of his) that I use in my talks. I think protein has a major role to play, but I haven’t climbed on board with his total hypothesis that the slight decrease in protein over the past few years is the cause of the obesity epidemic.
It’s interesting that Simpson and his co-authors are all insect biologists and came up with this idea from their study of bugs.
Cheers–
MRE
I say lets put T.Colin Campbell (10% protein advocate) and Dean Ornish (10% fat) in a room for a year and feed them a diet thats 80% carbs and see what happens. I’ll bet that their brains will turn into oatmeal from the lack of fat. Never mind I think were too late.
In response to Fred and Regina,
I also think it has a lot to do with the amount of carb intake. The percentage of carbohydrate consumption in the Atkins group is a lot higher than my understanding of what Atkins should be. Granted I haven’t read the newest book. But with the amount of weight these women needed to lose, they should have been consuming a lot less carbohydrates for a lot longer.
I am used to seeing closer to 5% carbohydrate during the initial induction phase (2 weeks is the minimum time, with up to a few months if the person has a lot to lose, or is highly resistant), and maybe 20% in the ongoing weight loss or maintenance phases.
At 6 months the average is almost 30% carbs and at 12 months 35% carbs. I’m not surprised that they gained weight back, I know I certainly would.
I’m not saying that protein doesn’t have anything to do with it, but I think the amount of carbs is a dead give away as to the results.
Just my opinion.
Hi Cathy–
I’m with you.
Cheers–
MRE
I just had to jump in to agree with this sentiment; somehow, lowcarbing seems to be more forgiving.
Maybe it’s because we eat so MANY carbs that even cutting down from 300 to 150 does a world of good.
My husband has a chronic illness and finds it difficult to stay on track when it flares up. Even doing low carb this half-assed way (I tease him that he’s doing “half-assedKins”) he’s lost almost 60 pounds.
The last three months, being housebound, he still lost seven pounds.
And his lipids look great. Low carbing has definitely been a great thing for him to do. Even if it is half measures.
Half-AssedKins! I love it.
You don’t even need to dig out your Atkins book to find out how long the Induction phase is. Just go to the official website.
http://www.atkins.com/articles/atkins-phases/phase-one/phase-1-induction/
Just thought this little tidbit of information was important for you to know.
Hi Mandy–
This is what the recommendation is of the people running the Atkins site right now. The researchers used whatever was in the original book, which, as I recall, was a lot longer than 14 days. Feel free to check and let me know.
Cheers–
MRE
Hey, quick question:
Does anybody else’s copy of PP or PPLP have a cover quote from none other than Barry Sears, Ph.D.? Mine says:
and
Also, while I’m going over my bookshelf, everyone is right on Dr. Atkins Induction. It lasts 2 weeks for everyone. It can last 6 months if you want it to. But really: the difference between 7g/meal (atkins Induction) and 10g/meal (pp Induction for heavy folks) is pretty small change, right? The difference is the allowed food list and mandatory veggies on Atkins that makes it a little harder in Induction. But with the ketosis focus, well, you get what you pay for, right?
At any rate, who are these people eating 30% carb calories on an LC diet? I’m closer to 10%.
As to Dr. Atkins, poor soul/dead guy. Shameless self-promoter, so I guess he deserves to be the Name for the LC diet in studies. If you and MD get out and bust hump in the marketing field the way Dr. Atkins did, maybe you can change the paradigm. Course, it’s easier to become the first model than replace the first model. And I know there were other LC diets before Robert Atkins ever saw his first obese person. But, the world is what it is. Should we go back to calling it the Banting Diet?
Hi Max–
Yep, Barry Sears gave us a cover blurb as we did him.
As to your last paragraph, I don’t even know where to begin, so I won’t.
Cheers–
MRE
Whoops, since there were more comments debating how long Dr. Atkins did and didn’t say to Induce for, let’s let the man himself tell it.
From Dr. Atkins New Diet Revolution, copyright 92, 99, 2002, 10th printing in paperback, page 122. Chapter: And Away You Go: The Induction Phase.
“The Induction Phase is not going to be your lifelong way of eating. It will last at least fourteen days, after which you should see a significant result.”
From page 159:
“A lot of people think of Induction as only two weeks, but it can be followed for a longer time. If you have a lot of weight to lose or have difficulty losing weight, you might want to do Induction for quite a while.”
He goes on to discuss when to go into OWL, which is too complicated to copy out of the book, but if you’re bored, don’t have a lot of weight to lose, are not very metabolically resistant and are willing to slow down your loss to get more food choices, move on. If not, you can do Induction “safely for six months or more.”
Conclusion: 2 weeks is right. 2-3 months may be right too. Like PP/LP it’s highly customizable.
Hi Max–
Thanks for the clarification.
Cheers–
MRE
Once again, Dr Mike, thanks for the great post.
The graphics are quite interesting too! Since I don’t have access to the article, I’ve wondered about several things that you’ve answered in your post.
Curious tho….did anyone determine WHY people dropped out? or didn’t follow the assigned plan? I think that might be equally interesting!
Now, I know random assignment of plans is the “best” way to conduct studies….but in the case of diets, don’t you think there would be different results if people actually chose the plan they were going to be on? I know for myself, the minute I was told I would be doing the Ornish plan I would have dropped out immediately! Even before discovering low carb, I knew I couldn’t follow a severely low fat diet. (for for me is much more effective than fiber, if you know what I mean)
I may highjack a few of your graphics (if you don’t mind) if I ever get to posting my own opinion of the study and reports about it.
Hi Cindy–
Most of the people dropped out of the study for scheduling reasons. A few got pregnant and several had ‘family’ reasons, whatever those might have been. Another large category was listed simply as ‘Other.’
The point about whether the dieters should have been randomized or selected the diet they wanted on their own can be argued either way. It would have been interesting to have given a bunch of people all four books, let them read all of them, then select the diet they would feel most comfortable with. I would love to see in a situation such as that which diet most would choose.
Feel free to use the graphics. They all came from the study.
Cheers–
MRE
Thought this might interest you. I love equating low-carb to cholera.
Hi Marjorie–
Sounds like a major case of sour grapes to me.
Cheers–
MRE
Wow,
I’m such a newbie! I just recently started the Atkins/Protein Power regimen, about 4 weeks ago.
I am over in the slightly anal camp, and I record all of my meal plans with calories, protein, and carb totals for the day. I’m wondering if anyone would like to read what a low-carber/protein life planner eats on a typical day and how the numbers play out over time.
I’d have to learn how to set up my own blog, but does this sound like it would be useful information to anyone? I could include recipes, as well.
Hi Rachel–
Go for it! Get your feet wet. You might want to take a look at the Discussion Forum (click at the top of this page) on this website. It has a lot of people who would be interested.
Cheers–
MRE