alt Hacker NewsHonestly, you can find studies to prove just about anything when it comes to nutrition. Too much money involved. Sometimes you have to use common sense or try different diets to see how your body reacts. I find "high fiber" and "low protein" to be a suspicious suggestion though. Protein generally has a small insulin response, your body actually needs protein, and if things like the "protein leverage hypothesis" are correct it can also help with satiety. Fiber, on the other hand, is literally food stuff that can't be digested. It can be helpful for your colon bacteria, but that's about it.
Just because an article comes from Harvard doesn't mean it's correct -- Harvard scientists were also behind the original food pyramid, and were likely paid off by the sugar industry.
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> Sometimes you have to use common sense or try different diets to see how your body reacts.
I sometimes wonder if the complexity of the human body doesn't stop us from seeing things that can have great positive effect on a set of people because it's counteracted by the effect on another set of people so the result in the whole is cancelled out. I now wonder if the statistic methods used in these studies take this into account.
All this to say that I approve of controlled self-experimentation, but you need to be very rigorous and brutally honest. Most people are not.
Beyond the protein insulin response... when you have protein with sufficient fat, the insulin effect is much, much lower still. I tend to suggest that people try to get about 0.5g fat to 1g protein (which is slightly more calories from fat than protein). I think the aversion to fat is problematic and likely a lack of sufficient well rounded fat intake is likely a factor in the fertility and other hormonal issues in western society today.
The recommendation wasn't for high fiber, low protein. It was moderate protein and higher fiber.
Fiber also gives your colon material to push against, adds volume to poop, and helps clean and clear you out when you poop.
If you're on a low-carb diet you should supplement fiber.
Unless you're doing something blatantly wrong or have a very specific disorder like coeliac, diet just doesn't have very much influence on health. There are a very wide range of diets that are more-or-less equally healthy, within a margin of error. Humans are highly adaptable omnivores that have evolved to survive and thrive on a broader range of foods than pretty much any other species. The data seems so mixed because the effect sizes of reasonable interventions are so small - a tiny signal drowned out by noise.
The entire problem is that most people in high- and middle-income countries are in fact doing something blatantly wrong - they are consistently eating vastly more calories than they use. Some of those people are ignorant of what 2000 to 2500 calories actually looks like, some are deluded, but a very large proportion know damned well that they're eating far too much and do it anyway.
The obesogenic environment that we now live in is partly due to the influence of the processed foods industry, but in large part it's simply a product of abundance. Before the late 20th century, it was simply inconceivable that poor people could afford to become morbidly obese. Agricultural productivity has improved beyond all recognition and the world is flooded with incredibly cheap food of all kinds.
We've spent the last few decades trying to push back against that with all manner of initiatives intended to endgender behavioural change, with very little success. It doesn't really matter what guidance we give people when they have shown a consistent inability or unwillingness to follow it.
If we're actually serious about the effects of diet on public health, I think there are only two credible options - extremely heavy-handed regulation, or the mass prescribing of GLP-1 receptor agonists. All of the other options are just permutations of "let's do more of the thing that hasn't worked".
Fiber greatly lowers your blood sugar response because you can't digest it. It also lowers your blood cholesterol for the same reason, so it's often recommended for those with a risk of CVD to eat more fruits and vegetables. It also protects against colorectal cancer for similar reasons.
Turns out just slowing down digestion can have a lot of benefits.
Also, most Americans eat very, very little fiber. Anything is an improvement. I believe the FDA recommendation is 30 grams a day, and most Americans eat, like, 2.
However, most Americans are not deficient in protein. They eat lots of meat, and very little veggies.