Episode 98: Steven Austad talks about aging and preserving human health
STEM-Talk
The Evolution of Time-Restricted Eating
Sachin Panda: Why do there seem to be sex differences in maximum lifespan in humans and other animals like monkeys? Sachin Panda: I think part of the reason for that is I think it reflects our evolutionary history. He says women turn off randomly one of their two X chromosomes in each cell in their body. But as women get older, it turns out that one or the other of their X chromosomes comes to dominate. It's pretty common in higher primates, although we do know of someone which men live longer.
Our guest today is Dr. Steven Austad who studies virtually every aspect of aging. He is a distinguished professor and chair of the Department of Biology at the University of Alabama, Birmingham.
In addition to being recognized for his aging and longevity research, Steve is also well-known for his background as a New York City cab driver, newspaper reporter and a lion trainer who then decided to become a biologist.
His research today involves developing lifestyle and pharmacological approaches to improving and preserving human health. He is particularly focused on figuring out why different species age at different rates.
Steve is the author of more than 190 scientific articles. His book, “Why We Age: What Science Is Discovering about the Body’s Journey Through Life,” has been translated into nine languages. He also writes newspaper columns and has written for publications like Natural History magazine, Scientific American and International Wildlife.
Show notes:
[00:02:53] Dawn opens the interview mentioning that Steve was born in Southern California, but that his family moved around so much, that he ended up attending around 20 grade schools. Steve explains that his father bought a travel trailer and moved the family around the country.
[00:03:57] Steve talks about how even though he was shy and introverted as a kid, he found a way to fit in with his classmates.
[00:04:40] Ken mentions how Steve’s career went through several reinventions before settling into a career in science. Among the various occupations Steve had were: a newspaper reporter, training lions and tigers for television and movies, and taxi driving. Ken asks Steve how he became a taxi driver.
[00:06:01] Steve talks about his time on the West Coast in Portland working as a newspaper reporter for the Oregonian.
[00:07:48] Dawn asks how it was that Tippi Hedren and Melanie Griffith had something to do with Steve becoming a lion trainer.
[00:14:39] Ken asks Steve about the suicidal duck whose reckless abandonment nearly resulted in Steve’s death at the hands of one of the lions he was training.
[00:19:21] Steve discusses why his fascination with animal behavior lead him to California State University to major in biology.
[00:23:24] Dawn asks what took Steve to the University of New Mexico for his postdoc.
[00:28:16] Ken asks how Steve landed his job as assistant professor in the Department of Organismic and Evolutionary Biology at Harvard University in 1986.
[00:29:59] Dawn mentions that Steve discovered that opossums of the predator-free barrier island of Sapelo Island lived 25 percent longer than their cousins on the mainland of Georgia. Steve discusses this and explains how this discovery played a role in his future research.
[00:34:13] Dawn points out that Steve left Harvard for the University of Idaho where he became a full professor and then next went the University of Texas. Dawn asks Steve about accepting a position in 2014 at the University of Alabama, Birmingham.
[00:41:32] Steve discusses his research into lifespan and healthspan and longevity and why some species age at different rates, with a particular interest in long-lived organisms like quahogs clams and hydra. He goes on to explain how this research led to what he refers to as the “Longevity Quotient.”
[00:48:42] Ken mentions that as a former Rhode Islander, he spent some time digging Quahogs and eating them.
[00:53:14] Steve gives an overview of how dietary restriction studies are performed on mice.
[00:59:39] Ken mentions that from Steve’s description it seems that modern humans are becoming more and more like laboratory mice.
[01:02:53] Ken mentions STEM-Talk episode 79 where Satchin Panda talks about time-restricted eating, and episode 7 where Mark Matson talks about intermittent fasting. Ken goes on to say that Mark made the point that the benefits of time-restricted eating or intermittent fasting is that it puts the organism, particularly the human, in a state of ketosis.
[01:04:09] Steve talks about the differences in the maximum lifespans of males and females in both humans and other animals.
[01:08:42] Ken recommends STEM-Talk episode 67 with Doug Wallace for listeners interested in hearing more about mitochondria.
[01:09:44] Dawn asks about metformin, which is a drug that many people believe has the potential to increase our healthspan and lifespan. She asks why it is that we’re not all taking metformin and if it really has such potential. She further asks about the status of the Targeting Aging With Metformin (TAME) trial.
[01:13:39] Ken mentions a recent study coming from the Miller lab, that suggested metformin might inhibit mitochondrial adaptations to exercise in older adults. He goes on to mention an even more recent paper out of the University of Kentucky and the University of Alabama, Birmingham has reported that metformin blunts muscle hypertrophy in response to resistance exercise training in older adults. Ken also mentions Steve’s continued interest in rapamycin and its effect on the health span of animals. Ken asks what Steve has learned and if rapamycin would still be his first choice for testing for a drug to target aging.
[01:20:08] Ken asks about the optimal and most efficacious dose of rapamycin for humans.
[01:21:10] Dawn mentions a paper Steve co-authored with Tuck Finch, discussing the role of the different APOE isoforms. Dawn asks about the ancestral isoform and why we see different isoform distributions today compared to hundreds of thousands of years ago.
[01:24:59] Dawna asks why we see different isoform distributions between different populations around the globe.
[01:26:29] Dawn asks how much of a role lifestyle versus genetics plays in healthspan and lifespan.
[01:28:58] Steve talks about of Fauja Singh, who is 108 and didn’t start distance running until he was in his 80s, and who ran a marathon when he was 101.
[01:32:17] Ken asks if Steve is still as confident as he was in 2016 when he made a bet with Olshansky over whether there will be one or more 150-year-old human by the year 2150.
[01:34:15] Ken asks why we haven’t seen someone exceed Jeanne Calment’s record age of 122 years that she reached in 1997.
[01:36:04] Dawn mentions that Steve continues to write articles and columns for newspapers as well as other news outlets. In addition to this Steve also has a website called, “Let’s Talk Science?” where an assortment of his newspaper columns and other writings can be found.
[01:37:47] Dawn closes the interview suggesting that Steve might want to explore writing a novel about a young newspaper reporter who ends up driving a Mercedes across California with a lion in the backseat, who then finds himself in a Hollywood mansion living with Tippi Hedrin and Melanie Griffin and watching over the lions and cheetahs that run through the house. Dawn suggests that has the makings of a good book.
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