Dr. Layne Norton: The Science of Eating for Health, Fat Loss & Lean Muscle

Exercise, independent of anything that happens with your body weight, you will be healthier. So, exercise is one of the only things that will actually improve your biomarkers of health without even losing weight ... It'll improve your insulin sensitivity, inflammation, all that stuff. So, everybody out there looking for a hack to be healthier–exercise is the hack.

There was actually a recent really large meta-analysis of over a million subjects, and basically what it showed was that for every 10g increase in fiber, there was a 10% reduction in the risk of mortality—and that extended, specifically, also to cardiovascular disease and cancer.

If you want to improve gut health... the three biggest levers you can pull is not eating too many calories, exercising—there is a connection between exercise and the gut—and fiber.

Of the macronutrients, protein is definitely the biggest lever that you can pull ... It doesn't take a ton of protein to get a lot of the muscle-building benefits ... The benefits really start to plateau out around 1.6 grams per kilogram of body weight. There's some evidence that maybe even up to, like, 2.4 or 2.8 grams per kilo may give like a little bit more benefit.

These watches... People are like, 'Oh, well, it told me I burned this many calories.' They are not accurate for energy expenditure ... There was a meta-analysis in 2018 I want to say, between a 28 and 93% overestimation of energy expenditure by these watches.

There are some pretty compelling studies showing that exercise increases your sensitivity to satiety signals. So, basically, you have the same satiety signals, but you're more sensitive to them when you exercise.

If you're going to lose weight, you have to invoke some form of restriction—whether it is a nutrient restriction (like low-carb, low-fat), a time-restriction (intermittent fasting, any form of time-restricted eating), calorie restriction (tracking macros, whatever). You get to pick the form of restriction, so pick the form of restriction that feels the least restrictive to you as an individual.

HDL is important because it's a marker of metabolic health. If you have high HDL, it suggests that you are metabolically quite healthy ... People who have high HDL will have good biomarkers of metabolic health.

When you look at LDL and you look at the lifetime exposure to LDL, it is like a linear effect on heart disease. And we know that it's actually not so much LDL, but it's more ApoB, but that tends to track with LDL just in general.

There is no situation where it is not a net positive to take somebody who drinks sugar-sweetened beverages and have them drink an artificially sweetened beverage.

What about artificial sweeteners for me? ... Do I think that they are healthful? Probably not. Do I think they're unhealthy. I would say, based on the current data, I don't think that they're unhealthy.

I think it's fine to consume saturated fat ... I think limiting it to 7-10% of your daily calorie intake is probably wise, again, based on the all the consensus of the evidence I've seen.

I would never tell people they need supplements ... Even something like creatine is going to be a very small effect compared to proper nutrition, recovery, and hard training.

The research seems to really clearly suggests that eating enough fiber, which is, again, a prebiotic—that that is a better way to get a healthier gut, per se, than probiotic.

What I would tell people is focus, probably, less on sugar; focus more on fiber. So, if you're eating 30, 40, 50, 60 grams of fiber a day, but your sugar's, you know, 80, 90 grams, I would not be that worried about it.

Touching on creatine, it is the most tested, safe, and effective sports supplement we have ... There are thousands of studies on creatine monohydrate now ... If you're using any other form of creatine, I think you're wasting your money.

You can't create a new version of yourself while dragging your old habits and behaviors behind you.

When you look at the research data and the meta-analyses on, say, time-restricted eating versus non, when calories are equated, there doesn't seem to be a difference in weight loss, fat loss, most biomarkers of health—same thing for low-carb versus low-fat.

I'm not somebody who likes to demonize individual nutrients. I just haven't seen really compelling evidence that seed oils are the root cause of the problems that are being suggested.

Food labels—which we like to think as being, you know, from upon high—can have up to a 20% error in them.

A lot of times people will say something like, 'Well, not all calories are created equal.' That's not true because a calorie is just a unit of measurement. That would be like saying not all seconds on a clock are created equal. Yes they are. All sources of calories may have differential effects on energy expenditure and appetites.

If you're worried about NEAT, tracking your steps can be helpful because people's step counts can spontaneously decrease when on a fat loss diet. They don't even realize it.

If you look at the literature overall on exercise and appetite, it's not always what you'd expect. Consistently, it seems to show that exercise actually has an appetite-suppressant effect. So, people don't tend to compensate at least fully for the amount of movement they do.

Six out of every seven obese people will lose a significant amount of body weight in their life. So why do we still have an obesity problem? They don't keep it off.

There's some evidence that saturated fat may not be great for the microbiome—that it reduces the prevalence of some of the more positive strange of bacteria.

My suspicion is probably if you're getting, like, 2 to 3, high-quality protein meals in a day, you're getting the vast majority of the benefits of protein.

Aspartame very clearly seems to have no effect on blood sugar or insulin. That has been repeatedly shown. Stevia doesn't appear to have much effect. Saccharin and sucralose, the jury is kind of mixed.

The placebo effect can actually change your physiology. People don't realize this. There's research showing that a placebo or the power of suggestion is basically as powerful as some pharmaceuticals.

The more adipose tissue you have, the more aggressively you can diet without negative consequences.