Atkins Diet Increases All-Cause Mortality – NOT!

You may have seen the article in Huffington Post by notorious Atkins-basher, Dr. Dean Ornish. He opens his irrational diatribe with this paragraph:

“A major study was just published in the Annals of Internal Medicine from Harvard. In approximately 85,000 women who were followed for 26 years and 45,000 men who were followed for 20 years, researchers found that all-cause mortality rates were increased in both men and women who were eating a low-carbohydrate Atkins diet based on animal protein.”

At the same site, another low-fat acolyte, Dr David Katz, is eager to pile on with the headline, “The Beef with Atkins”. He gives us a clue as to whether he has any preconceptions with this statement: “Do I think eating a high-meat, low-plant diet increases risk of death and disease? Hell ya!” and goes on to try to explain away the unexplainable.

From all this you might conclude that someone has done a study with a lot of people doing Atkins for a lot of years and that there is now proof that, compared to a control diet, Atkins led to higher death rates. If that’s what you thought, and that’s clearly what Ornish and others of his ilk, would like you to think, you would be completely wrong.

Where to begin. I suppose the first point to make here is that nobody in this study was doing Atkins. The lowest level of carbohydrate consumption reported was in the range of 180 g per day. That doesn’t resemble any version of Atkins that I am aware of.

Maybe, even more importantly, is the nature of the study itself. It is an observational study which means that no intervention was tested. What the researchers did was enlist a large number of people, in this case, nurses and other health professionals, and surveyed them with questionnaires over a period of years. Food recall questionnaires are highly unreliable (to get a sense of just how unreliable they are, have a look at this commentary by Chris Masterjohn – The reported results appear to be based on data gathered in 1986 and then extrapolated. A single questionnaire is used to try to determine what people ate over the previous year. How accurately can you tell me what you ate over the last month? Last week? You can see why this might be a tad unreliable. Still, I think you will be surprised just how wildly unreliable this kind of data is if you visit Chris Masterjohn’s site. Yet, it is the standard for these kinds of studies.

In this study, the food recall questionnaires considered “plausible” reported caloric intakes ranging from 500 to 3500 kcal per day. How many people get by on 500 kcal per day, do you think? Not too many. So, in the analysis, median or average numbers were chosen which still look, in all groups, to be significantly lower than what any American presently eats. The men reportedly ate about 2000 kcal per day while the women ate between 1600 and 1800. That should make for a pretty slim bunch of typical Americans! Interestingly, these absurd numbers for caloric intake are averaged while the analysis is done to determine the amounts of carbs, proteins, fats, etc in the various deciles. One wonders what would the data have looked like if they averaged the macronutrients and broke the caloric intake into deciles. The first decile would be 500 kcal per day, the next 800 kcal per day, the next 1100 kcal per day, etc etc. Do you see the problem? Of course it would be absurd to think that the first groups in the series could eat so few calories and actually live. That study would never get published. However, when these data are flipped around and the analysis is done the other way to determine macronutrient proportions by decile the study gets published. In what universe does that make any sense?

The next thing you need to know is that observational studies do not tell you anything about what causes what. They are useful for generating hypotheses which can then be tested using intervention trials to see if a hypothesis based on the original observations is valid. The reason that relying on the original observations is fraught with hazard is because, as I said, you cannot draw conclusions about causality, but also because of the high likelihood there will be unaccounted for factors that  explain the observation rather than the variables you hypothesized were responsible.

In this study, they divided the entire study population into deciles based on their reported consumption of carbohydrates. The percentage of calories from carbs ranged from about 37% to about 60% (for comparison, I eat about 5%). They then arranged two other decile groupings based on another comparison which looked at their consumption of animal sourced fats and proteins vs. vegetable sources. They found that the lowest carb group that ate the highest amount from animal sources had 23% higher all-cause mortality compared to those who ate the fewest calories from animal sources. Now you can see why the vegan zealots are very pumped about this and why their leaders are using every opportunity to hitch their anti-Atkins message to these findings, in spite of the fact that the study had nothing whatsoever to do with the Atkins diet or a vegan diet, for that matter.

So, 23% greater chance of dying – that sounds serious. Is it really? Let’s look a bit further. Apart from the problems inherent in determining causality, another issue that arises from the use of observational data of this sort is the size of the observed hazard ratio. Given all the potential problems with this kind of data, one wants to see a hazard ratio which is either below 0.5 or above 2.0. The hazard ratio here was 1.23, which falls significantly short of the mark.

The researchers also did a sensitivity analysis to determine how large a confounding variable they would have to have overlooked in order to void these findings and came up with 20%. In other words, a factor that could affect mortality by 20% would have to have been missed in arriving at these results. That sounds pretty big, right? How could they miss something so big?

Well, consider this. In an earlier study using questionnaires from this same group, it was determined that the use of hormone replacement therapy (HRT) conferred significant protection from cardiovascular disease. The hazard ratio was 0.39, well under the 0.5 point at which you should normally take notice. That sounds pretty good. Where can I sign up for some HRT?

Not so fast! A subsequent study which tested this observation using a large randomized control trial actually found that HRT increased the risk of CVD, by a factor of 1.29 (in a randomized controlled trial, a hazard ratio of 1.29 is considered to be significant). The unaccounted for factors in this case were five times as great as the 20% needed to void the carbohydrate mortality link in the current study. Five times as big and it was still overlooked! This is precisely why one should not draw conclusions from observational data until it is tested through properly designed intervention trials.

Okay, I will grant you that it’s not always possible to do the kinds trials needed to test every observation and that, by default, we may need to rely on the evidence we have in hand from observational studies. If that is the case, then we need to work within some parameters which will improve our chances of being right. In the case of smoking, for instance, the hazard ratios for harm when smokers are compared to non-smokers are north of 10. Remember that you want to see ratios above 2.0 before you get too concerned about observational data. Remember, also that the ratio reported here was 1.23.

Secondly, you want to see other things in the data. For instance, a dose-response effect would be supportive and a lack of it would suggest problems in the data. Dose-response means that as you increase the factor that you think is causing mortality, you want to see the mortality rates rise alongside those increases. In this study, there was no dose-response effect. Although the published study does not provide information for each decile, we can see what happened at the 1st, 5th and 10th decile. The high-vegetable group was actually eating more animal protein and fat and more saturated fat than the high-animal group at the 1st and 5th deciles. Only at the 10th decile are they eating less and, even then, not hugely less (30% vs. 45%).

Okay, while you are trying to get your head around that, consider that the reported hazard ratios for all-cause mortality at the 5th decile still favoured the high-vegetable group, the ones who are eating the most animal protein and fat at this point! Such an inconsistency in the data surely suggests there are other significant factors at work here. How this got by the reviewers and into print is a mystery to me.

What about the high-vegetable low-carbers? First of all, they are hardly low-fat vegans. They were eating about 30% of their calories from animal fat and protein. And, when you look at this group’s all-cause mortality rates, they have a hazard ratio of 0.80, which means 20% less mortality than people eating less animal fat and protein! How does that support the vegan or low-meat or low-fat agendas? It doesn’t. For the men, those who ate 38% of their calories as fat vs those who ate 24% had a 19% reduction in mortality. Let me emphasize that – the people in the high-vegetable group who ate more fat, more animal fat and more animal protein had a lower mortality rate. Why didn’t Ornish’s headline say: “Eating More Meat and Fat Reduces Your Risk of Dying”? This would be just as valid, in fact, more valid than the ridiculous headline suggesting that the diet had anything to do with Atkins and mortality.  This part of the study findings is not mentioned in either of the Huffington Post pieces or in any other mainstream media coverage that I have seen. You have to ask yourself “Why?”.

I could go on but there are other sites you can visit to get more informed criticism. I recommend Chris Masterjohn’s site mentioned above. Also, Denise Menger, a new voice of reason in the diet debates, can be found at where her deft evisceration of “The China Study” is also worth a read. Another fairly recent and very funny commentator is Tom Naughton at his blog I recommend his movie, “Fat Head”, as well. Also, have a look at the usual reliable sources  such as Jimmy Moore’s and the Eades at (although I haven’t seen a comment from Mike yet).

So, what can we learn from this? The study is so deeply flawed, it is hard to figure out whether there is anything here of importance. As I said at the beginning, all this type of study can do is generate hypotheses that need further testing. One intriguing hypothesis, of course, is that a higher fat, higher animal protein, lower carb diet high in vegetables seems to confer a better all-cause mortality rate. That would be the one I would like to see pursued. Funny how that sounds eerily similar to the diet recommended in the most recent Atkins book, too. Ornish and Co. are, of course, free to pursue their agenda, too, and I wish them luck. However, it cannot be a happy time for this crowd. As more evidence piles up demonstrating the benefits of low-carb over low-fat, they do seem to be getting more desperate.

I think what we are actually witnessing here is a paradigm in its death throes. This would explain the stunning perfidity of its proponents who appear willing to pull out all the stops in fighting their rear-guard action to save a belief system that is rapidly devolving into shambles. No Geneva convention here, folks. Flat out lies and misrepresentions are justified when defending the faith. And a lazy and, and possibly corrupt, media is all that is needed to keep the lies coming. Stay tuned. I am sure we will see more of the same.

ps – edited to correct error picked up by commenter

Low-Carb Baby Trial (n=1)

Isabelle is one year old now and thriving. She has pretty much stopped breast feeding but still gets a little formula. She gets a varied diet of foods high in protein and fat along with lots of non-starchy vegetables, all of which she eats with gusto. Her breakfasts now are gently scrambled egg with spinach puree, kind of a baby version of eggs florentine. She drinks water, mainly, but still likes to sample our beverages at the dinner table. Apart from some formula, she never gets any liquid sugars as juice or otherwise, something I would recommend to anyone whether they are doing low-carb or not. When she was born she was a tiny bit below the 50th percentile for height and weight. Within a few months she began to climb up the growth chart to the point where she is now at the 95th percentile for both height and weight. She is very active, crawls like a bullet and pulls herself up on the furniture and walks while holding onto things. She took her first unassisted steps these last couple of days. Lots of talking, too, but in a language in which we are not fluent. It is fun to witness the emerging personality. She is definitely a go-getter. When Alex was very young his first vocalizations were little sing-song syllables like “daa-daa-ah”. Isabelle’s are more like the sound of a revving motorcycle, “rrrrrRRRR, rrrrrRRRR, rrrrrRRRR”. She has us in stitches when she does that. At the same time she has a sweetness that melts your heart. One smile and her daddy is reduced to a puddle. She adores her brother and lights up whenever he enters the room. Even the cat gets little hugs and gentle touches now that Isabelle is mobile enough to catch her.

She is certainly not demonstrating any adverse effects from a diet devoid of sugar and starch. Perhaps the most interesting development is her position on the growth curve since Alex, Anne and I are all of average height. I have warned Alex to be very nice to her as she is going to be in a position to kick his butt before long. He is actually a very good big brother, gentle and caring.

The other thing we notice is that Isabelle has never had any rashes or illness except for one bout of a very mild malaise with a slight fever a few months back. No rashes at all. I remember Alex used to get yeast rashes and all the usual respiratory infections. In fact, we all seem to be avoiding these things since we started eating low-carb. In the high-carb past, I always succumbed to one or two major colds every year. Now, when these things are in the community, I might experience a day or two of mild sniffles but nothing more. Same for Anne. The other thing I have noticed is that I never get cold sores anymore, either. I used to get them pretty reliably when I went skiing. The UV light at high altitude seemed to trigger it and I would get a few bouts every winter. Now it happens very rarely and, when it does, the sores are mild and resolve quickly. There is definitely an immune system benefit from low-carb that needs to be further explored in the research.

Similarly, I can’t remember the last time Alex had a cold. I think he missed one day of school last year and none the year before. He is a very sturdy little boy with lots of energy. He is good-natured with never any acting-out or discipline issues, at home or at school. He does well academically and has developed close friendships with other boys his age, all of whom we approve of. There are never any outbursts of temper or whining. Anne and I often talk about how blessed we are in this respect. Physically, he is slender like little boys are supposed to be with good muscle development and definition. His skin glows and his eyes are bright. Anne thinks he will be Hugo Boss model material when he gets older but I suspect all moms think that way. I really think the absence of sugar and highly refined carbs from his diet is a major factor in his robust health and well-being. He eats more carbs than the rest of us but there is no sugar in our household and the carbs he does eat are the less-refined types. For instance, for breakfast he will have a one-egg omelette (because one egg is un oeuf) with a piece of whole wheat toast covered in almond butter. Water is his preferred drink. Our biggest challenge with him is when he is outside our home, of course. Everywhere you go people are pushing sugary things. When he is surrounded by his little buddies who are all indulging, it is hard for him not to indulge, too. At his soccer game yesterday, they handed out cartons of some kind of juice-like abomination during half-time and I noticed he drank some. He felt crappy when he got home and spent the rest of the afternoon lying on the sofa. I don’t think he will do that again.

Okay, I am sure these musings about kids and low-carb are of limited general interest. I will, nevertheless, keep you updated on progress in this modest clinical trial of mine. In the meantime, everyone, and I mean everyone, needs to work together to get the sugar and particularly the liquid sugar out of our kids’ food supply. I challenge anyone to show me a shred of evidence to suggest this is not a good idea.