Peter on nutrition, disease prevention, sleep, and more looking back on the last 100 episodes

I think there's evidence that you can take NAD precursors, NR and NMN being the two most common, and increase NAD levels ... I think what's not been demonstrated is there is any phenotypic benefit from doing that outside of very pathological states. In other words, if you take a quote 'normal person,' a normal aging person, and do that, is it bringing any benefit to them in terms of lifespan or healthspan? I would say the answer right now is no.

If you had an experiment that was done where people are going to eat 3,000 calories a day spread out over the course of 12 hours versus people that are going to eat 3,000 calories spread out over 6 hours, is there any difference between them? And I think the answer today is no.

I think you need to ask yourself before you go on an aggressive TRF regimen, how much muscle mass can you afford to lose? And if the answer is none—which should be the answer for most people by the way, most of us don't have the freedom to lose any lean mass—then you gotta make sure you're not restricting protein and that you're thinking about when you can refuel in relation to exercise.

I'm probably less concerned with the light from electronics before bed than I used to be. I think I used to view that as absolutely deadly for sleep; I'm not sure that that's really true. It could be more the stimulation that often accompanies blue light, because blue light is often coming from electronics, that can be more the issue ... It might not be your phone per se that is killing you; it might be what you're doing on your phone.

I think most people would agree that if you had a colonoscopy every 1-2 years, the likelihood that you could ever develop a colon cancer, while maybe not zero, is so remote that you could effectively take colon cancer off the list of the top 10 reasons why someone dies of cancer.

I think most of the benefit of time-restricted feeding is accrued through caloric restriction.

The good news is this tool called exercise... has an unbelievable impact on your lifespan and healthspan—probably bigger than anything else—and it's available to everyone. It has the least barrier to entry. The drawback is it's the hardest.

And what I'm about to say is going to sound incredibly bold and controversial: It seems increasingly true to me, which is nobody should ever die from colon cancer—and I would add the same for esophageal and stomach.

By the time you're in your late 30s or early 40s, if you have any measure of apoB that's even north of the 20th percentile, that should be completely lowered. So, in some ways, I would view an apoB ceiling of 60 as the limit, and that's probably at about the 5th percentile. You sort of want everybody to be below the 5th percentile.

I just don't see a reason to have an apoB ever north of 60 mg/dL ... If you have an LDL cholesterol below 30 or an apoB below 40 mg/dL for a very long period of time, I think the odds that you're going to suffer ASCVD are incredibly low.

How many cancer deaths do we have each year? So, I think for 2020, we're looking at probably 600,000 people in the US died of cancer. And how many of those were in the digestive system? 170,000 of the 600,000.

In our practice, we think 40 is the age at which a person should have their first colonoscopy if they have no history of colon cancer. About when I had my first one was 40 or 41.

I've now come to appreciate the magnitude of the value that is brought to a person's lifespan and healthspan by having higher cardiorespiratory fitness and more strength.

80% of patients have neoantigens on their cancers that are recognized by their immune system ... The holy grail of cancer therapy is undoubtedly immunotherapy. In other words, anytime you can get the immune system to recognize your cancer as non-self, you're winning the game.

I really think that, in 10 years, we're going to basically be using designer-based immunotherapies to eradicate most solid organ metastatic cancers.

When you look at organ-specific sites, colon cancer is generally in the top three leading causes of death for both men and women.

Pharmacologically, lower apoB to somewhere in the 20-30 mg/dL range for everybody in the population while someone is in their 20s, can you eliminate ASCVD? And I think the answer is probably yes.

That's where we're probably seeing the biggest deficits are these women that show up with no muscle mass eating no protein, doing very little strength training. I mean, to me, that is a recipe for a shorter life, but more importantly, a lower quality of life.

I remain incredibly unoptimistic—I don't know if I'd call that purely pessimistic—but I remain quite uninspired by the entire NAD stratosphere.

The evidence is overwhelming that infantile levels of apoB are not deleterious in any way.

And that's why I think grip strength is a great proxy for longevity.