Problems with Nutrition Research

Standard

Appearances to the mind are of four kinds.
Things either are what they appear to be;
Or they neither are, nor appear to be;
Or they are, and do not appear to be;
Or they are not, and yet appear to be.
Rightly to aim in all these cases
Is the wise man’s task.
Epictetus, 2nd century AD

If you pay attention to the news then you don’t go a day without hearing about nutrition research. Alcohol, chocolate, meat, fat, carbs, protein, fiber, sugar, this diet, that diet, and a galaxy of supplements are under constant scrutiny. You may also notice that studies seem to frequently contradict one another. (The health effects of alcohol are a notable example.) It’s easy to become confused and frustrated as you search for accurate information. (And that’s just with the valid research out there. Throw in the junk “research” behind bogus supplements and snake oil and you may simply want to give up being informed.)

I’m neither a researcher nor a statistician but I respect the need for solid research into health, fitness, nutrition, and the like. I understand that valid research requires a large number of study subjects. The best studies are designed as double-blind placebos. Finally, research results must be replicated several times over in order to be seen as valid and worth taking seriously. Beyond that, I don’t have a good grasp of statistical methods so I can’t always tell if the conclusions drawn from the research are accurate. Thus I’m often confused by what I see and hear around nutrition research.

If you consider yourself a well-informed, educated, healthy person who finds yourself confused by conflicting nutritional studies then an article in the New York Times, More Evidence That Nutrition Studies Don’t Add Up, may help you understand your frustration. The story discusses the shoddy research practices of Cornell University researcher Dr. Brian Wansink.

The article goes beyond Dr. Wansink’s malpractice to discuss general, widespread nutrition research problems:

“Dr. Wansink’s lab was known for data dredging, or p-hacking, the process of running exhaustive analyses on data sets to tease out subtle signals that might otherwise be unremarkable. Critics say it is tantamount to casting a wide net and then creating a hypothesis to support whatever cherry-picked findings seem interesting — the opposite of the scientific method. For example, emails obtained by BuzzFeed News showed that Dr. Wansink prodded researchers in his lab to mine their data sets for results that would “’go virally big time.’”

“’P-hacking is a really serious problem,’” said Dr. Ivan Oransky, a co-founder of Retraction Watch, who teaches medical journalism at New York University. “’Not to be overly dramatic, but in some ways it throws into question the very statistical basis of what we’re reading as science journalists and as the public.’”

“Data dredging is fairly common in health research, and especially in studies involving food. It is one reason contradictory nutrition headlines seem to be the norm: One week coffee, cheese and red wine are found to be protective against heart disease and cancer, and the next week a new crop of studies pronounce that they cause it. Marion Nestle, a professor of nutrition, food studies and public health at New York University, said that many researchers are under enormous pressure to churn out papers. One recent analysis found that thousands of scientists publish a paper every five days.”

Further:

“In 2012, Dr. John Ioannidis, the chairman of disease prevention at Stanford, published a study titled “’Is Everything We Eat Associated With Cancer?’” He and a co-author randomly selected 50 recipes from a cookbook and discovered that 80 percent of the ingredients — mushrooms, peppers, olives, lobster, mustard, lemons — had been linked to either an increased or a decreased risk of cancer in numerous studies. In many cases a single ingredient was found to be the subject of questionable cancer claims in more than 10 studies, a vast majority of which “’were based on weak statistical evidence,’” the paper concluded.

Nutrition epidemiology is notorious for this. Scientists routinely scour data sets on large populations looking for links between specific foods or diets and health outcomes like chronic disease and life span. These studies can generate important findings and hypotheses. But they also have serious limitations. They cannot prove cause and effect, for example, and collecting dietary data from people is like trying to catch a moving target: Many people cannot recall precisely what they ate last month, last week or even in the past 48 hours. Plenty of other factors that influence health can also blur the impact of diet, such as exercise, socioeconomic status, sleep, genetics and environment. All of this makes the most popular food and health studies problematic and frequently contradictory.

In one recent example, an observational study of thousands of people published in The Lancet last year made headlines with its findings that high-carb diets were linked to increased mortality rates and that eating saturated fat and meat was protective. Then in August, a separate team of researchers published an observational study of thousands of people in a related journal, The Lancet Public Health, with contrasting findings: Low-carb diets that were high in meat increased mortality rates.

“’You can analyze observational studies in very different ways and, depending on what your belief is — and there are very strong nutrition beliefs out there — you can get some very dramatic patterns,’ Dr. Ioannidis said.”

Read the article to learn more.

If this topic interests you then you should also read Congratulations. Your Study Went Nowhere, also from the New York Times. Among other things, it discusses an interesting problem with research publication. That is research with positive findings gets published far more than research with negative findings.

For instance, let’s say my study finds evidence that eating peanut butter increases IQ. Meanwhile, six other studies find no relationship between peanut butter and IQ: “Nothing to see here folks!” My positive study is more likely to be published than the negative studies. This is a type of publication bias. Positive studies are thus more likely to be mentioned in the news even if they’re outnumbered by negative studies. The article describes two types of biases:

Publication bias refers to the decision on whether to publish results based on the outcomes found. With the 105 studies on antidepressants, half were considered “positive” by the F.D.A., and half were considered “negative.” Ninety-eight percent of the positive trials were published; only 48 percent of the negative ones were.

Outcome reporting bias refers to writing up only the results in a trial that appear positive while failing to report those that appear negative. In 10 of the 25 negative studies, studies that were considered negative by the F.D.A. were reported as positive by the researchers, by switching a secondary outcome with a primary one, and reporting it as if it were the original intent of the researchers, or just by not reporting negative results.

We never hear a TV news reporter say, “Nine studies found absolutely no relationship between food X and cancer.” In other words, we only hear the bell that’s rung, not all the other bells that aren’t rung. The obvious problem is that if shoddy research findings are reported (vaccines linked to autism is a prominent example) and we may hear reports from multiple credible sources, then we start to believe false information. There are serious consequences to this problem.

 

 

Dr. Peter Attia & EatingAcademy.com

Standard

A lot of recent posts on this blog have been about the high-fat/low-carb ketogenic diet. Along these lines, is the fantastic blog called the Eating Academy from Dr. Peter Attia, MD. Attia is a former surgical oncologist. He spent time at Johns Hopkins Hospital in Baltimore as well as the National Institutes of Health in the National Cancer Institute. (Go here to read more about him.)

Those are pretty impressive credentials and he’s a major reason why I’ve become convinced that much of our conventional low-fat/high-carb government-sponsored nutritional advice is bad news, and that a high-fat (including saturated fat) low-carb strategy is the ideal.

He left surgery because:

“During the fifth year of my residency I became a bit frustrated with certain aspects of medicine and health care, in general. In particular, I grew tired of the notion that we (doctors) did little to keep patients healthy, and were basically the last line of defense against, well, death, once patients become ill. The concept of “preventative medicine” received some lip service, but didn’t really have any chops as far as I could tell. In addition to this frustration (and others), I really missed quantitative and analytical problem solving.”

(I love his observation that doctors do little to prevent ill health and that they’re the last line of defense. That’s a huge issue to me. The best way to address a disease–particularly lifestyle/obesity-related illnesses like diabetes, cancer and cardiovascular disease–is to never get it. No matter how well we’re cared for, once we’re ill, we’re in trouble.)

Attia is also a fairly decent swimmer, cyclist and avid weight trainer. Thus he has an interest in nutrition not only for health but also for athletic performance. He discusses his personal nutrition journey in four parts: why he decided to lose weight, how he lost weight (ketogenic diet), how he reduced his heart disease risk, and how a low-carb diet affected his athletic performance. It’s all very detailed and very compelling.

Attia’s blog is an incredibly detailed ongoing discussion on nutrition, cholesterol, fat, weight loss, eating for athletic performance, disease avoidance, etc. He really delves into the science and some of his posts are quite a bit over my head. I love though that he discusses things like what he actually eats (here and here.) He also discusses a fascinating new sports supplement UCANN Superstarch (look here and here; I’ve been using this stuff recently and I like it A LOT.)

If any of this sounds interesting to you, go to the Start Here link and read more.

A Ketogenic Diet Experience: the Savage Man Triathlon Double

Standard

Guest blog post from Mike Piet

Mike Piet is a former client of mine and a very good friend. He’s also an elite-level triathlete, multiple-Ironman finisher, participant in many strange and grueling adventure races, marathons and all types of long bike excursions. We speak often of endurance activities, weight training, nutrition, and mobility and restoration work. I was very happy when he offered to write about his experience in two recent triathlons while fueling himself via the low-carb/high-fat approach. This is his tale…

Two triathlons back-to-back

On September 14-15, I participated in the SavageMan double triathlon, a tough weekend of racing in Western Maryland that includes an Olympic distance triathlon on Saturday and then a half-iron distance triathlon on Sunday.  While the Olympic is tough, it is the half- that has earned a reputation as one of the hardest races around: It features a bike course with over 6000 feet of climbing, including two uncategorized climbs.  The first of these, the Westernport Wall is 1.2 miles long with an average grade of 12% and a max grade of 31%.  Stand there long enough and you are bound to see someone literally start rolling backward.  Watch this video and you’ll get a feel for the brutal nonsense.

I have done the double two years now, but this year was different.  This year I was going to try it on a high-fat/low-carb eating protocol – I was going to use a ketogenic diet to race in a state of dietary ketosis.

I won’t get into the nuts and bolts of the ketogenic diet but in the big picture, the diet has me burning fat instead of carbs for the vast majority of the race.  This is in contrast to the typical high-carb diet favored by most endurance athletes.  The limitation of the high-carb approach is that you must continually consume bars, gels, sports drinks and all kinds of food in order to avoid running out of fuel.  This means carry lots of additional fuel and tweaking the fuel mix just right so you don’t undergo dietary distress.

For more information, I highly recommend the work of Dr. Peter Attia at the Eating Academy, Ben Greenfield, and Drs. Stephen Phinney and Jeff Volek at the Art and Science of Low-Carb.  Each of these resources explain the ideas and science behind ketosis and the ketogenic diet much better than I, but the basic premise is that in going into ketosis, your body burns fat for fuel instead of carbohydrate.  Given that fat stores are significantly (20x) larger than glycogen stores, it is a compelling experiment for long distance athletes.

A ketogenic state can’t be achieved overnight, so in the eight weeks leading up to the Savage Double, I started to change my diet over.  Approximately 70% of my daily caloric intake came from fats (olive and coconut oils, butter, heavy cream, natural peanut butter), 20% from protein and 10% from carbs.  Think Paleo or Atkins, but with dairy.  My daily carb intake was generally between 50-100 grams per day, depending on training volume, which equates to two medium bananas (48 grams), one cup of rice (45 grams), or four slices of wheat bread (52 grams).  In other words, not the typical American diet. The table below shows a typical day’s food intake. I tended to be less exacting on the weekends, but did not stray far from the guidelines:

[table "1" not found /]

The numbers in the table are in grams.  As you can see, a majority was in fat – on this day I actually overshot my fat goal and was short on my carb and protein goals.  You will also notice that my sodium is high – this is a crucial aspect to doing keto right.  When carbs are minimized, the kidneys leach out sodium faster than normal, so it is important to increase sodium intake to maintain healthy blood pressures and the muscles’ electrical impulses. Going into the race, my plan was to rely on this protocol and not use my usual pre- and mid-race fueling strategies.  I was going to minimize my calories taken in, typically on the bike, because I was going to fuel my race with my own fat stores.  Going into the race, my diet remained much the same in terms of the ratios above.  On race morning both days, I had a cup of upgraded Bulletproof Coffee – a recipe borrowed shamelessly from Ben Greenfield.  One cup of coffee, 2 tablespoons each of butter and coconut oil, 4 tablespoons of heavy cream, a packet of Stevia, ¼ teaspoon of cinnamon, and a ½ teaspoon of cocoa.  I put all this in a blender until it was foamy on the top and completely mixed.  This totaled 650 calories with 72 grams of fat, 4 grams of carbs, and 1 gram of protein.  If nothing else, not sitting down to eat a meal and having all my calories contained in a cup saved a ton of time and a lot of hassle.  Thirty minutes prior to the race, I sipped a cup of chicken bouillon, with 1 gram of sodium in it.  Five minutes before the race, I used a packet of Vespa Jr., a product that helps tap into fat burning (www.vespapower.com).

Both days I carried a drink mix on the bike that was a mixture again borrowed from Ben Greenfield.  Here’s the recipe:

It calls for UCAN Superstarch, a gluten free complex carbohydrate that stabilizes blood sugar; electrolyte pills, and various other ingredients.  In short, it’s not the usual bike bottle full of sugar based energy drink.  However, on Saturday the mouth of my bottle was clogged and I couldn’t get anything out.

I rode the entire bike course without taking in any calories.

Coming off the bike I felt pretty good, so took off on the 10K run – felt good through the first aid station where I didn’t take anything, and then the second aid station.  In the interest of continuing the experiment, while I probably should have taken something at mile four, I ate nothing. I finished the Olympic tri without ingesting a single calorie since the Bulletproof Coffee in the morning, and I felt good! So good, in fact, that I was able to run a second 10K with my dad, who was also doing the race and finished the bike just as I had finished the run.  I consumed three pretzel sticks at one aid station while running with him, but otherwise water.

Results: 1st place in my age group and 12th place overall. My finishing time was 2:25 on a notoriously difficult course.

The next day was the half-iron and the protocol was the same. Same coffee, broth, Vespa pre-race.  I made sure both bottle tops were functioning because the half is such a long day.  I have only gone under 6 hours twice on this course, even though on a “normal course” my half-iron PR is 4:45.  It was a hard day right from the start and I didn’t feel like I had good legs for the ride.  I used both bottles of my drink, but no other calories – for this race, I am usually a buffet on two wheels throwing back gels, bars, and energy drinks.  Going into the run, I was not feeling good – a hard bonk was setting in and I had struggled the last 20 miles on the bike.  The first five miles of the run were mostly walk, but I came away from the low carb protocol (and you may have noticed, very little sugar), and started drinking Coke from the very first aid station.  It was all I took – no water, no food, no energy drinks.  One or two cups at each aid station – my body was craving the sugar – and interestingly, slowly, I was able to recover the back half.  The last seven miles I was able to run an honest race, something that did not seem possible when I first came off the bike.

The whole race was an incredible learning experience, and while the second day did not go as well as the first, I raced a half ironman on the heels of an Olympic (plus an extra 10K) on very few total race calories.  My recovery and refueling time on Saturday was compressed, and I think if done differently, I would have focused on that more – putting in more calories, ensuring that I stayed in ketosis, and doing more recovery and mobilization.  On Sunday, given the type of effort it is, I would have ingested more carbs earlier in the day on the bike – as Peter Defty of Vespa says, with the high fat diet, when carbs are ingested properly, they work better than if following a normal eating protocol.

Like any eating protocol, I advocate following something that works for the individual, and is sustainable.  Going keto has worked well for me. It is allowing me to go farther on much less, but may not be right for everyone.  Despite the misconception that eating a lot of fat will beget fat, I lost about 5 pounds and raced at about 165.  My body fat remained between 6-8%.

I am awaiting my blood work from Wellnessfx.com. I purchased their baseline panel and got tested prior to going keto and will be interested to see where and if the numbers have changed. I am really interested in seeing my cholesterol number.  My LDLs were a little high. The rest of my numbers were low.

Interestingly, the science suggests that contrary to medical guidelines and popular thinking, this ketogenic protocol could help lower cholesterol. I’ll post those numbers once they’re available.  For anyone interested in the hard science behind ketosis, I again recommend Drs. Phinney and Volek’s books – while technical, they provide excellent information based on science and research.

Thanks to Kyle for letting me guest post on his blog.  If anyone has specific questions about my experience and going keto, I can be reached at mdpiet@aol.com.