diet

All posts tagged diet

Mainstream medicine has become increasingly standardized over the past few decades.

Standardization has some benefits: reduced inequality, improved procedures for minimizing mistakes, and increased predictability. Those attributes are often easier to verify than health effects.

Standardization is not so great for promoting innovation (standardizing a few building blocks may promote innovation, but that’s not what medicine has done). Yet medicine is an area where we have a relatively high need for more innovation.

It would be nice if one system of medicine provided everything that I want from medicine. Just like it would be nice if one company could provide all my transportation needs, or every type of food that I want, or an operating system with all the software that I want to use.

Alas, none of those seem close to being feasible this decade. Yet I get the impression that many more people expect it of medicine than is the case for food or transportation.

I’ve reached an age when it’s valuable to ask a good deal from medicine. So in addition to a standard doctor, I’ve engaged with a competing “brand” of medicine.

Specifically, the functional medicine practitioners at Chris Kresser’s Adapt180.

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Book review: The End of Alzheimer’s Program, by Dale Bredesen.

This sequel to The End of Alzheimer’s is an attempt at a complete guide to a healthy lifestyle.

Alas, science is still too primitive to enable an impressive version of that. So what we end up with is this guide that would overwhelm anyone who tries to follow it thoroughly, while still lacking the kind of evidence that would convince a skeptic.

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A new study has provided evidence that a healthy lifestyle can reverse aging, as measured by epigenetic age: Reversal of Epigenetic Age with Diet and Lifestyle in a Pilot Randomized Clinical Trial. This is the second study to show that epigenetic age can be reversed in humans (here’s a reminder to read the first).

They used the Horvath DNAmAge clock.

After a mere 8 weeks of a healthy lifestyle, the subjects’ DNAmAge was 3.23 years younger than the controls (and 1.96 years younger than the pre-trial DNAmAge of the treatment group).

The lifestyle interventions weren’t labeled as paleo, but they closely resemble the lifestyles that are recommended by Chris Kresser, Steven R. Gundry, and Dale Bredesen. The diet comes about as close as the diet of a typical paleo enthusiast to avoiding foods that have been available for less than 10,000 years. The recommended foods that I consider the least paleo are “coconut, olive, flaxseed and pumpkin seed oil”. The diet is more plant-based than the stereotypical paleo diet, but it’s well within the normal range of hunter-gatherer diets.

The study has a bunch of the usual limitations, such as a small sample size (18 people in the treatment group). There are also reasons for mild concerns about conflicts of interest, as some of the researchers work as functional medicine physicians, so their careers are mildly dependent on the popularity of the lifestyle approach being studied. As far as I can tell, that is likely to cause a level of bias that is rather ordinary for nutrition-related research. Oh, and the instructions are listed as “Patent pending”, but it’s unclear why they would meet the novelty requirements for a patent.

My main doubt comes from the difficulty of figuring out whether DNAmAge measures causes of age-related health problems, or whether it’s just measuring symptoms. I’m slightly more than 50% confident that epigenetic changes have some causal influence on aging.

This kind of trial raises questions about how well patients follow the instructions – most would find it difficult to “Avoid added sugar/candy, dairy, grains, legumes/beans”. The paper describes how they checked on patient compliance, but I didn’t see any data indicating what they found about compliance. So there’s some risk that they were especially lucky about getting patients to follow their instructions, and maybe future studies of this nature will show much weaker results due to poor compliance.

Lastly, it’s a bit odd that the control group appeared to age 1.27 years in 8 weeks. Maybe they were depressed about not getting any treatment? (This isn’t the kind of study where blinding is feasible). More likely it was just noise, but that’s a reminder that the small sample size provides lots of opportunity for luck to dominate the results. Even if we assume perfect measurement, there’s plenty of room for variation in lifestyles. Uncontrolled lifestyle changes, such as someone getting fired, could mess with the results enough to matter.

Baze

Convenient, affordable blood tests seem to be important tools for improving health. See my review of The End of Alzheimer’s for hints about why they’re important.

Talking20 and Theranos raised some hopes, then they failed.

Now comes Baze. They shipped me a device that I pressed against my arm. I waited a few minutes, took it off, and shipped it back. I was a bit uncertain about my ability to read the light that changed color to indicate the device had collected enough blood, but I seem to have gotten it right.

Half the time that it took to complete my test involved walking to the nearest FedEx drop box, which is a good deal closer than the nearest LabCorp or Kaiser lab. I had no need to worry about unpredictable delays waiting for a technician to be available to extract my blood.

I got 10 nutrient levels tested for a sale price of about $50. Many of those tests aren’t available on privatemdlabs.com, and the ones that are available are around $50 per nutrient. Life Extension has more of the tests, including Selenium (list price $88, but I normally wait for their spring sale), and Omega-3: $79 for a test that requires me to extract blood from my finger on my own. I had trouble getting enough blood that way, and never got a result, presumably because I didn’t do it well enough. So if I tried to test those 10 nutrients without Baze, I’d have paid maybe $500 and only gotten 7 or 8 results.

Are Baze’s results accurate? I’ve been tested for several of the nutrients previously, and the Baze results for those are similar enough to be reassuring. Their technology seems to have a decent pedigree.

So far, it sounds almost too good to be true. Is there a catch? Maybe. Baze does have a business model that makes me a bit nervous.

Baze is part of Nature’s Way, and tests nutrients in part in order to sell us vitamins in order to correct any deficiencies that it detects.

That does bias Baze away from providing the tests that are most valuable for influencing health-related decisions.

It also biases Baze toward recommending more supplements than is optimal. I don’t see any clear signs that they’re erring in that direction. I also see a distinct shortage of strong arguments in favor of their recommendations.

For vitamin D, they classified my level of 58.3 as excessive, when it’s only about 10% above the level I was aiming for, and there are many people advocating higher levels. That’s a clear sign that they’re not pushing too many vitamins on us.

Yet for choline and omega-3, they classified my blood levels as optimal, yet are still sending me those supplements. There’s at very least something wrong with their explanation here. Yet in both cases, I see some plausible arguments from independent sources that my levels are a bit below ideal, and I had been mildly concerned that I wasn’t consuming enough.

Maybe they’ve got a good explanation hiding somewhere on their blog, but the easy-to-navigate parts of their website are written more for people who want simple and convenient answers from a respected authority. Something feels wrong with their attempt to act like such an authority without providing more evidence of competence than I’ve seen.

They’re also sending me vitamin E and magnesium. I’m pretty confident that I’m consuming a bit more than the RDA for both of those, yet my test results say I’m a bit low in both.

I’m concluding that they have not yet given into the temptation to sell too many vitamins, but they’re putting little effort into reassuring me about this.

Their choice of which tests to do reassured me a bit. They test B12 via methylmalonic acid rather than the less sensitive direct test, and they avoid some nutrients that are more risky to supplement (iron, B6, A, calcium).

Potassium is an important nutrient that many people don’t get enough of. Baze doesn’t do anything with potassium, because potassium supplements are heavily regulated, and because low potassium levels can have causes that ought to be treated by doctors.

Fiber is another important nutrient that many people eat too little of. But that’s rather tricky to evaluate via a blood test – insulin resistance measures say something relevant, but it’s hard to quantify the connection, and doing so might raise novel regulatory issues.

With pretty much all of the nutrients that Baze sells, the evidence for benefits from supplementing is underwhelming, resting mainly on correlations. Where I’ve seen RCTs that test supplementing, only vitamin D seems to show a clear benefit.

I hope Baze focuses more on increasing the variety of biomarkers that it tests for, and less on selling vitamins. I would like to use them for more testing, but not for getting more vitamins. Optimizing our vitamin pill consumption is far from the most valuable goal that this new technology can accomplish.

I suppose the more valuable uses of the technology work best with a fair amount of doctor involvement, and the medical system changes slowly enough that Baze might have needed to introduce the less valuable uses first.

Baze seems good enough now that most people with below-average health (that includes most people over 60) will get a bit of benefit from Baze.

Warning: they report results in different units than I’m used to, so I needed to look up several conversion factors to compare my Baze results to my prior results.

Book review: The Paleo Cure, by Chris Kresser.

I wish I had read this when I went paleo 7 years ago. It’s more balanced than the sources I used. Alas, it was published shortly after I finished a big spurt of learning on the subject.

It still has a modest number of ideas that seem new to me, and many ideas that I’d have liked to have known when the book was first published, but which I found through less organized sources.

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I’ve mentioned Blue Zones approvingly several times on this blog (here, here, and here).

Alas, there are reasons to doubt that they’re unusually healthy. The paper Supercentenarians and the oldest-old are concentrated into regions with no birth certificates and short lifespans makes a decent case that they’re mostly just areas where ages have been overstated. There are some relatively unhelpful arguments about who’s right on Andrew Gelman’s blog and on Bluezones.com.

As a consequence, I’m slightly decreasing my opinion of some foods that I was encouraged to eat by the Blue Zone memes: whole grains, beans, olive oil, and sweet potatoes. Sweet potatoes still seem likely to be quite healthy compared to the average American food, but I’m now uncertain whether they’re better or worse than the average paleo food (I previously considered them one of the best foods available). The rest of those foods seem no worse than the average American food, but I’m less optimistic about the safety of the average American food than I previously was.

I’ve also become less confident in the safety of a diet with less than 10% of calories from protein (Blue Zone Okinawans in 1949 got 9% of calories from protein), but I’d already decided not to pursue a low protein diet.

I’ve slightly decreased my opinion of Steven Gundry and Valter Longo

H/T William Eden.

Book review: The Good Gut: Taking Control of Your Weight, Your Mood, and Your Long-term Health, by Justin Sonnenburg and Erica Sonnenburg.

I had hoped this book would help me improve my gut health. Alas, their advice is of limited value, mostly focusing on changes that I’d already adopted based on other types of nutritional ideas, such as eating more fiber from diverse sources. That limited value is probably due mostly to the shortage of useful research on this subject, rather than to any failing of the authors. Research on these topics seems hard due to the complexity of the microbiome, and the large variation between people.

The book convinced me to eat more kimchi, and left me wondering whether to try consuming more bacteria in pill form.

The book repeats warnings that I’d read elsewhere about the dangers of antibiotics, and the problems that arise from having an insufficiently diverse microbiome, such as autoimmune diseases.

I have been placing heavy emphasis on fiber in my nutritional strategies, while having a gut feeling that the concept of fiber left something to be desired. The book pointed me to an alternative concept: microbiota accessible carbohydrates (MACs), which mostly means carbs that aren’t absorbed by the small intestine. A diverse set of MACs feeds a diverse set of microbiota, which at least correlates with good health.

Alas, it seems impossible to reliably measure MACs by analyzing food in isolation – different people’s small intestines absorb different substances. There are also complications such as erythritol, which is mostly absorbed in the small intestine (and is then removed without doing much), but about 10% of which ends up feeding microbiota in the colon. So I’m still stuck with estimating my MAC consumption via the standard fiber estimates, and taking care to get it from diverse sources.

The Sonnenburgs explain that food preparation affects absorption. Flour is absorbed faster than less-processed grain, and the meaning of “flour” has changed over the past century or so, from something that was ground coarsely and eaten soon after, to something that is ground very fine, and stays on a shelf long enough to go rancid if it is whole-grain flour. That nudged me toward a more nuanced position on grains. The “grains are not food” rule was a simple way to improve my diet, but there are clearly big differences between the best whole grains and the worst grain-derived products.

It also helps me understand how grains, as typically used, gradually morphed into mostly being junk food without an easy way to detect the worst effects. More sophisticated machines to grind the grains led to a texture that was more quickly absorbed, leaving less for microbiota. The switch away from whole grain flour was likely, in part, a gradual adaptation to a system where the flour was ground at an increasingly distance from the home, and became more likely to go rancid if the germ wasn’t discarded.

The book has a section on how infants get a microbiome, which explains why it’s really hard to find or create a good substitute for human milk.

The Sonnenburgs have unusual heuristics about when they wash their hands, designed to reduce pathogens while welcoming good bacteria. They avoid washing after gardening or petting the family dog, but are careful to wash after going to places where they could get germs from many other people – malls, petting zoos, etc.

I’m discouraged by the news that microbiome treatments such as Fecal Microbiota Transplantation (FMT) may be regulated as drugs. It seems like regulations should be modeled somewhat more closely on food, or blood transfusion, regulation. Like food, FMT should have broader goals than just combating specific diseases, should provide diverse inputs, and should bear some resemblance to what naturally enters our bodies. Like blood transfusions, FMT should be reasonably safe unless there’s something unusual about the donor.

The book’s advice overlaps a lot with paleo-like advice to go back to how our ancestors ate, played, etc., with a rather balanced approach to borrowing from our grandparents’ lifestyle versus borrowing from hunter-gatherer lifestyles. The book is solid, often at the expense of being exciting.