It's a false dichotomy, of course. Using PubMed abstracts to search for the "optimal" diet is like searching for a needle in a haystack with a magnifying glass. That said, the other side of the coin is to use the Kitavans or the Inuit--populations that 99% of us know literally nothing about, except what we've read in our quest for dietary information--as "just so" stories. So we're left in the sandbox talking past each other.
When I taught middle and high school integrated science, I used Richard Feynman's quote to define science: "Science is the experiment." But where do experiments come from? What drives them? And this gets back to "science vs. anecdote." What drives science? I'd argue that it should be driven by observations. Patterns. Which lead to questions. Which lead to hypotheses. Then research. And, of course, research stimulates new questions and hypotheses and patterns. Recall that it was anecdotal evidence that led Jenner to create a vaccine for smallpox. A common observation about milkmaids that didn't get smallpox.
Today, we're left to fend for ourselves. Research is less purely knowledge-driven than it used to be, in my opinion. Agendas rule the day. Today's citizen scientist is an endangered species. Lavoisier, van Helmont, Benjamin Franklin--they would be labeled "Internet crackpots" in the contemporary milieu.
Personally, I wouldn't want anyone to extrapolate from my dietary experiments. I have celiac mutations on chromosome 6. Also, I carry an allele for cystic fibrosis. What other genetic aberrations do I carry that make it hard to generalize from what I know to be true in my own experience? What's best for me is quite possibly not best for the population at large. And, despite the fact that my dietary experiments have achieved outstanding results for me personally, I could very well be expressing a "live fast, die young" phenotype, characterized by early peaking, sexual mania, and early senescence.
So what brings me to this ramble? The safe starch debate, of course! Will you trust in PubMed articles about the glycation of dietary sugars to show you the way? Will you use the Kitavans or Inuit as your dietary model? Or will you attempt your own "new synthesis"? Or have you already found your own new synthesis in the writings and teachings of others?
Nice question! Research (both clinical and anthropological) plus the anecdotes of others make a useful starting point for personal experimentation, and that's about all you can ask for. Our lifetimes are limited and the combinations of variables to be tried are close to unlimited, so without a starting hypothesis, you'll just flail around randomly. Ya might get lucky, but ya probably won't.
When I started out on this journey, I had a loose plan with some loose justifications (low-carb, since Atkins had worked for me years earlier, plus the carb-insulin hypothesis, plus a sprinkle of Paleo 1.0 thinking). Over time I pushed harder on the actions that got good results, and learned through painful experience to avoid the actions that got bad results. And when research or anthropological observation seems to contradict my experience, I think about why that might be, but as far as my actions are concerned, I end up going with my experience (although I'm careful not to push it onto others, who may differ from me in key ways).
The safe starches debate is a perfect illustration of this: I've tried that experiment -- twice -- and it didn't work for me. I agree that amylase + evolutionary theorizing make a seemingly convincing argument in favor of dietary starch, but I'm not going to try endless variations (eat them plain, eat them buttered, eat Old World tubers, eat them on the new moon, hanging upside down, when the tide is out, and so on) just to satisfy the theory, no matter how well-supported it ends up being in the literature. My body is happy without starch, and unhappy with it, and if I have to try out fourteen different versions of it, each one lasting several months while I gain weight and my joints get stiffer, just to find the one golden version that "allows" me to eat a potato -- well, I hope you can see the return on investment is not exactly compelling.
ETA: This question reminds me of this other question. Also, it allows me to post a link to my favorite comedian doing my favorite routine. ;D
Excellent post, though I firmly believe that activity level determines glucose tolerance far more than one's genes. Unless you're actually closely related to some outlier population like the Inuit or Kitavans, you'll probably be in the same fairly narrow range of glucose tolerance as every other healthy, active human on Earth. Even so, I'd be willing to bet that an active Inuit would have been able to eat starch without any ill-effects.
Most people aren't as active as our design demands and suffer the consequences of it as a result. No wild humans sat around and had animals commit seppuku in front of them so they could be eaten. We had to work hard like every other species to stay alive until just recently. If your activity level is evolutionarily inconsistent and you've totally nuked your mitochondrial density and the corresponding enzymes, don't expect to be able to tolerate carbohydrates.
Genetic defeatism is simply a smokescreen. It's time that we stopped bullshitting ourselves and others and actually started to be honest about how active we truly are and how it impacts our tolerance of carbohydrates. If 10-20g of carbs actually makes a huge difference for you, you probably have the activity level of a cadaver. May as well be honest about it. If you're highly active and you can't eat that 20g, check to see if you have a navel, because you may have been created in a lab or perhaps hatched from an alien egg.
In terms of starch consumption, if I saw my blood markers or any other markers deteriorate, I might change things. Same thing goes for fat consumption. Even if you are looking at studies all the time, there is always a chance you are in the tail of the bell curve and things don't work that way for you. So I mainly use the scientific data and ethnographic data to generate hypotheses about the best diet.
I will read information from any source easily available and I am willing to try things that make sense unless they seem unduly risky. The most frequent caveat is that I'm not going to swallow a handful of supplements every day and I'm not going to eat/drink things I find vile.
After I try things, the opinions of others really don't matter because I either thrive or I don't, I either like them or I don't. Simple as that.
It's still a novelty for me to feel this good day after day, so I'm not going to worry about what hidden problems could be incubating. I had overt problems before, and I don't now, so I'll worry about the future when it comes.
Sources like PubMed might give me a spark of an idea, but ultimately it's my personal experience with something that counts. My fear instinct will prevent me from experimenting with something too wacky.
So, I would anecdotally establish for myself that A results in B. I'll continue with or stop A depending if B is good or bad. Science can be used to explain B.
Phew - good one!
I live or die by science when it comes to my work - anecdotes will not suffice when submitting a report to a government agency regarding the status of environmental contamination. But by science here I mean lab analysis of samples taken, toxicity tests and the likes.
But science is a BIG umbrella - and reports that you can access on PubMed are only one small piece of 'Science'.
I think that it is very important when reading published studies to read the WHOLE report, rather than just the abstract which I have seen many people do. I like to dig into the meat of what they are looking at and what kind of statistics they have performed on their data, where they got their data from or whether they collected it themselves, what the control group looked like etc, etc. Just because it's published does not make it reliable or even remotely beleivable!
So in my personal life its very anecdotal with some science mixed it - what makes me and my family feel better? Are we feeling bad - maybe we should go and get some lab ananlysis done to see what could be the culprit (checking D levels or the likes)
We're not left to fend for ourselves. We have each other. While our genes may pre-dispose us for certain issues or others, it can be avoided by our epigenome. We can enable or disable genes via methylation. The question is how?
Science is not a dead end, we can all explore it, and draw conclusions. Both anecdote and pure science have value. It's a question of discovering what really is. We might not find it all, but damn it, we will try!
We are all n=1 experiments, but as we collaborate, we can discover all of the nuances of truth. There are many paths, and communication leads to n=2, n=3, n=4... n=n! Not all paths will work for everyone, but some paths will work for more than one. Fuck the conventional, if it's wrong, but love it, if it's right. Not everything is applicable, but perhaps almost everything is permissible.
Why should we care if someone labels us internet crackpots, when others will be able to take advantage of our advice, and what of it? If we're right, we can help others, if we're wrong, at least we tried, and we reserve the right to be corrected, and to learn. Over time, the truth will expose itself through experimentation.
Life is risk, and gamble. The question is which paths are the most likely to be right? It doesn't matter, we'll try many of them and expose the answers. Observe, guess, question, try, test, retest, rinse, conjecture, consider, repeat.
I'd rather be wrong and experiment to find out for sure, than to be right and accept without questioning, or reasoning. Conventional Wisdom is death, it's kow-towing to so called authority without it having earned it. Experts aren't. And yet, it does get somethings right. So, pick and choose what works for you, and share the results.
I think a scientific approach can give you better information to base your decisions upon. I think looking at Kitavins or Inuit can be much different than looking at anecdotes.
Ideally with science I would like to see different people argue what it all means so that I can evaluate peoples arguments where I might be deficient on the science end. This is easier than learning 4 to 6 years of biochemistry but has its flaws as well.
In terms of the safe starch debate, the people in favor of the safe-starches seem to have better arguments to me. Rosedale seems pretty sketchy to me, and his attempts to gloss of his errors concerning whole blood vs plasma measurements is one of several issues that makes him look not too reliable.