Continuing my review / summary (essentially chapt 4 and 5) of Outlive. Part 1 available here.
1. Recall that Attia’s mantra is getting us to use Medicine 3.0 which, unlike Medicine 2.0 (which was about living longer with disease), is about delaying the onset of disease. So, to be clear, “longevity” to Attia isn’t merely about extending your age; it’s really about living a stronger and healthier life for as long as humanly possible.
2. Gene-wise, the TLDR on Attia’s book is that whilst our genome is immutable our genetic expression can be influenced by — surprise surprise — exercise and deprivation of nutrients (i.e. eating less).
He cites a 2007 study which found that “older people who were put on a regular exercise program shifted to a more youthful pattern of gene expression after 6 months.” (p.70)
3. Attia also discusses genes like APOE (linke to Alzheimer’s) and FOXO (which, according to him, is like a Cellular Maintenance Dept which, when activated, gets other genes to repair/recycle cells throughout out body).
4. Chapt 5 titled “Eat Less, Live Longer?” is the one which goes on at length about caloric restriction (CR). I’ve written a bit about this already (both in Part 1 as well as other pieces) but to recap:
a) when we overeat (or don’t have prolonged pauses in our eating) glucose floods our system non-stop and, in addition to its benefits, contributes to the maintenance of ‘zombie’ cells i.e. damaged or diseased cells which, if allowed to spread, pulls down the body’s health in general and even speeds up ageing.
b) by restricting the amount of glucose in our system (or by using alternative sources of fuel, eg ketones and the ketogenic diet) our bodies can kill/recycle the zombie cells, build new ones and, voila, ageing is slowed down and we’re healthier.
Attia claims CR is virtually proven the animal world.
“The life-extending effect of CR seems to be almost universal. Numerous labs have found that restricting caloric intake lengthens lifespan not only in rats and mice (usually) but also in yeast, worms, flies, fish, hamsters, dogs, and even, weirdly, spiders. It has been found to extend lifespan in just about every model organism on which it has been tried, with the odd exception of houseflies. It seems that, across the board, hungry animals become more resilient and better able to survive, at least inside a well-controlled, germ-free laboratory. (p.81)
5. In bio-speak, CR activates an enzyme called AMPK which, according to Attia, is like the “low-fuel” light in our dashboard which then initiates a cascade of actions.
Just like you’d begin driving more intentionally / conservatively if your fuel gauge was nearing Empty, the body also switches into Careful mode when AMPK turns on. Eg, AMPK stimulates the production of more mitochondria and begins recycling cells and getting the body into the process known as “autophagy”.
Autophagy represents:
“the catabolic side of metabolism, when the cell stops producing new proteins and instead begins to break down old proteins and other cellular structures into their amino acid components, using the scavenged materials to build new ones. It’s a form of cellular recycling, cleaning out the accumulated junk in the cell and repurposing it or disposing of it.” (p.82)
Attia declares that autophagy is essential to life.
“If it shuts down completely, the organism dies. Imagine if you stopped taking out the garbage (or the recycling); your house would soon become uninhabitable.” (p.83)
6. Chapt 5 ends with Attia expressing optimism that rapamycin (the drug which showed improved longevity results with mice; chapt 5’s opening pages have a long history on this) will be available for people soon.
I’m less enthusiastic about that; not very keen on taking controversial drugs to “live longer”. Period.
Gotta stop here. In future posts I’ll share what Attia said about obesity and T2D (practically the same problem, in his view), heart disease, cancer and Alzheimer’s (and other neuro=-degenrative diseases).
These “four horsemen” take up a chapter each in the book.
