Wednesday, October 13, 2021

No, I don't need to Just Try It

 One of the common responses I get when I provide critical* feedback of a diet or exercise idea, is that I should, “just try it”. But no, I shouldn’t. And the suggestion that I should indicates a lack of understanding of science. Either the science underlying the specific topic or of scientific methodology in general and why it is the way it is. 

Science underlying the topic

For the topics of both nutrition and exercise science we have 70+ years of published research. The research is not all confined to ivory tower laboratory experiments and deals with people eating in the real world and athletes competing in their sport. 


We have enormous amounts of research to back our conclusions. Many landmark studies that exist have been running for decades. 


The basic findings of these research programs have all been repeatedly replicated with enough variations to demonstrate broad generalizability. Outcomes are clearly predictable. 


As such, no, some new (or old) exercise tool is not going to be some exception to these patterns.

And, no, some new diet is not going to show that actually, this, that or the other was actually the key all along. 

Nutrition is NOT always changing

The obvious comeback to me pointing out that there is more than half a century of research backing nutrition science would be the claim that it’s always changing. I even had a nutrition professor say that during the unit on the history of nutrition science. But if you look at the basics and broad eating patterns instead of focusing on details, there has been little change. 

  • Every US food guideline has said that Americans should eat more vegetables and fruits and fewer calories added with sugar and oil/fat.

  • Eating fewer calories than you burn is the key to weight loss - everything else is single digit percentage fiddling with details.

There are more consistencies than just this and there is more consistency than changes.

Scientific Methodology

My personal experience with an exercise or diet is basically irrelevant. When the published, replicated results and my personal experience disagree then the correct conclusion is that I am wrong. 


Personal experience with a topic is not an experiment. You are not controlling for confounding factors in any way. 


With dieting this usually just a matter of a person liking whatever diet was the one that they could best live with. When my friend uses a low carb diet with periodic fasting to get back down to a healthy weight then more power to them. But if they say I should do that they are going to run into the brick wall that I am miserable when fasting and really like carbs. 


Or the person has bought into bogus health claims. Your diet is not making your blood acidic. So if the low-acid diet** gets you to eat more vegetables and less high calorie density foods then your improvements are from the fiber and better calorie balance. You didn’t control for confounding factors and you are attributing success to the wrong thing. This is exactly why understanding the basic science and doing controlled experiments are so necessary. 


Ye Olde exercise tool is not great for everything. No tool is. But if adding that tool got you to actually do more than you were doing before you will see some improvements. It is basically true (for most things) that more exercise will produce some improvements even if they are modest or inefficient. 


If your shoulders are getting tired from holding your sword up then sure, gada exercises will help with that, but that doesn’t prove they are good for anything else. Or that they are cost-effective. Or safe.


I will, however, reserve the right to get grumpy about specifically dangerous diets and exercises.

The history of this

The history of what was learned by humans who “just tried it” is well illustrated by the history of medicine. Because there are a staggering number of medical treatments documented in historical sources that just don’t work. But some humans tried them and became convinced that they worked. And then it ended up being written down by somebody called a doctor (or equivalent in their language). 


In short, humans have hyper-active pattern recognition; it’s hard-wired into our brains. This is useful in many basic life situations but can also go badly wrong. We think that A caused B when they are in fact unrelated. 

Good reasons to do things

There are of course plenty of good reasons to do something that don’t have to do with optimal outcomes. Where I get grumpy is when a person is really just describing their personal preference as if it were the best idea for everyone.


Exercise plans that fit your circumstances, equipment and motivation are great.


Eating patterns that are sustainable for you and improve nutrition are great.

But don’t insist that I need to just try it.


*critical here in a technical sense, not just destructive criticism


** the low-acid diet I’ve seen actually recommended eating oranges which are the most acidic food that humans eat :-D


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