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The Epigenetic Clock: Are You Biologically Older or Younger Than Your Chronological Age? Podcast with Ken Raj

We tend to think of age in terms of the number of years we have been alive – meaning our chronological age. But the year that you were born is not necessarily an accurate measure of your health or your life expectancy. We are coming to realize that a better predictor is your biological age – and that can be quite different from your chronological age. So how do you learn your biological age? And what can you do with this information?

In this episode of humanOS Radio, I speak with Ken Raj. Ken is a Senior Scientific Group Leader at Public Health London, and has worked extensively with Dr. Steve Horvath of UCLA in developing and interpreting genomic biomarkers of aging. They are best known for developing the “epigenetic clock,” a tool that predicts life expectancy by examining age-related changes to DNA methylation, then using that information to calculate biological age in relation to chronological age. The epigenetic clock is able to predict life expectancy with remarkable accuracy, with a margin of error of plus or minus three years.

In this podcast, we discuss:

-How the epigenetic clock uses DNA methylation to compare biological to chronological age.
-Whether DNA methylation changes are the “drivers” or the “passengers” of biological aging, and how direct a role they play in the aging process.
-Whether or not epigenetic changes can be passed down from generation to generation.
-Whether or not someone with a biological age greater than their chronological age is more likely to develop certain pathologies.
-What diet and lifestyle factors have been researched to show an impact on epigenetic aging.

To learn more, check out the blog!


Is the Ketone beta-Hydroxybutyrate Good for Memory? Podcast with Professor John Newman from UCSF and The Buck Institute

Our memory is fundamental to us as humans. The remarkable capacity of the human brain defines us as a species. And variation in our minds is one major aspect of what makes each of us different from one another. Without a robustly functioning memory, our ability to interact with the world – and to relate to one another – is seriously impaired.

We can carry on relatively well if we lose a limb, or even certain organs. But if our memory is erased, we are erased, in a sense.

Everyone knows this on some level. This is likely one reason why large surveys of the public often find that dementia is the most feared disease – because our mind and our memory so profoundly defines us.

But another reason why diseases associated with aging and the brain are so feared is because they are recalcitrant to treatment. For example, drugs developed to address Alzheimer’s disease have the highest failure rate of any disease area (99.6%). And the situation isn’t much better for other neurodegenerative conditions, or for age-related cognitive decline in general. We need a new approach.

In this episode of humanOS Radio, I speak with John Newman. Dr. Newman is a geriatrician (a physician who specializes in the care of older people) at UCSF, as well as a professor at the Buck Institute for Research on Aging. He is chief investigator at the Newman Lab, where he is exploring ways to harness metabolic signals to promote health and resilience, particularly in older adults.

Dr. Newman’s research focuses predominantly on ketone bodies – molecules produced in the liver when glucose is scarce, either due to restricted intake or prolonged physical activity. So we tend to think of them primarily as an alternative source of fuel, particularly in the context of a low carb diet. However, they are also intriguing with respect to aging, because of how they function as molecular signals, and how they influence gene expression.

In this podcast, we discuss:

-How ketones are generated in the body

-Why most medical doctors tend to think of ketones as being harmful

-How beta-hydroxybutyrate influences gene expression – turning on or off genes

-How gene expression goes awry in the aging process

-How BHB functions as a signaling molecule to regulate inflammation

-Why animals on ketogenic diets live longer and exhibit better memory as they age

-Ketogenic diets and aging/longevity

-Why exogenous ketones are exciting but there is much yet to learn about them before we fully understand their therapeutic potential


Is the Paleo Diet Good or Bad for Aging? Podcast with Professor Michael Rose

Why do we age? The fundamental causes of aging at the molecular level are relatively well established. But the question of why aging happens in the first place is a more challenging one, one which has bedeviled evolutionary biologists and philosophers for years.

You might think, intuitively, that the process of natural selection would gradually eliminate senescence. Aging increases mortality, and organisms that experience impaired function and ultimately die would not be able to produce as many offspring as one that was able to live (and to reproduce) indefinitely, or at least for a much longer timespan. So, you would assume that this would result in selection for organisms that live much longer, generate more offspring, and ultimately the causes of age-related deterioration would fade from the genome.

Yet aging is very commonly observed. Why is that?

Natural selection is strongest in early life. This makes sense – the natural environment is full of predators, disease, and other perils that often kill organisms when they are young and vulnerable. Consequently, genes and pathways that enhance survival and reproduction in early life are likely to be favored – even if they come at the cost of problems later in life, when selection is comparatively weak.

But is aging inevitable? Can it be slowed, or postponed, or stopped altogether?

In this installment of humanOS, Dan talks with Michael Rose. Dr. Rose is a Distinguished Professor of Ecology and Evolutionary Biology at UC Irvine. He is a prolific biologist whose research into the evolution of aging has effectively transformed that field. Rose’s laboratory has been testing the theory of antagonistic pleiotropy for nearly forty years, through artificial selection experiments in fruit flies.

In what was perhaps his most famous experiment, Rose allowed flies to only reproduce successfully if they laid their eggs late in life. He discarded the eggs of any flies that laid eggs before they reached fifty years of age. Over a few generations, this population of flies evolved longer lifespans. Why might this be? Remember that natural selection is strongest early in life, and becomes weak later on. In theory, if adults reproduce when they are older, natural selection is apt to favor genes that enhance resilience (and reproduction) later into the lifespan.

Dr. Rose’s research into aging has also drawn him to some interesting (and possibly controversial) notions about evolutionary changes in the human diet, and how our age may influence how adapted we are to modern agricultural foods. To learn what that means, and its potential implications, check out the interview!


Studying Preindustrial Societies Informs us About How to Be Healthy. Podcast with Professor Herman Pontzer

For the vast majority of human history, our species lived hunter-gatherer lifestyles. We can therefore learn much about how humans probably once lived by studying preindustrial societies.

Research on preindustrial societies has consistently shown that these people have exemplary health. And when we consider that modern humans are succumbing to chronic diseases at an alarming rate, we clearly have much to learn from preindustrial people.

In this episode of humanOS Radio, I speak with Professor Herman Pontzer about what he has learned from his research on hunter-gatherers. Herman’s findings led him to develop the counterintuitive hypothesis that how physically active we are each day may scarcely affect how many calories we burn in the long term…

… no, I’m not kidding.

As he explains in the podcast, however, this hypothesis in no way discounts the importance of being physically active – far from it!

Tune in for more on Herman’s fascinating research on physical activity, diet, and more.


Why Using an iPad at Night Disrupts Your Sleep. Podcast with Jeanne Duffy

Did you get enough sleep last night?

If not, you are not alone. Self-reported sleep data suggests that Americans are getting less sleep than we need. One study that examined 669 adults found the average sleep duration was just 6.1 hours, which is simply not enough. Short sleep is associated with a plethora of problems, ranging from impaired immune function, worse glucose tolerance, and increased risk of traffic accidents. People who report less sleep tend to weigh more, and are more vulnerable to psychiatric conditions such as depression.

So why do we struggle to get enough sleep? Well, we know that the most powerful cue for our biological rhythms is bright light. Visible light regulates circadian rhythms by interacting with light-sensitive neurons in the eye. And our patterns of light exposure have changed dramatically over the past decades, due to the invention and spread of artificial lighting. Even when it is pitch black outside – when we would normally be asleep – we are often bathed in light. It’s not hard to imagine how this interaction might affect our sleep, and perhaps our health.

In this episode of humanOS Radio, Dan speaks with Jeanne Duffy. Jeanne is an associate professor of medicine at Harvard Medical School and a sleep researcher at Brigham and Women’s Hospital. She has worked on some compelling studies that rigorously investigate how alterations in the light environment impact sleep and circadian rhythms.

In one recent study, she and colleagues examined how using iPads at night affected melatonin secretion and sleep patterns, and the results are pretty enlightening. To learn about what they found, and what you can do yourself to improve circadian alignment, please check out the podcast!


An Introduction to Heart Rate Variability (HRV). Podcast with Phyllis Stein

Stress is something we all experience all too frequently. While each stressor we experience has distinct effects, the effects of different stressors accumulate, and when the resultant load is excessive, we are at increased risk of a range of ailments, from gastrointestinal problems to cardiovascular diseases. So, to avoid the amount of stress we experience exceeding our bodies’ capacities to cope, it would be useful to have a way to monitor how we’re responding to stressors.

In the last few years, numerous wearable devices that claim to monitor how we’re responding to stress have become available, and most of these measure either heart rate variability (HRV) or pulse rate variability.

In this episode of humanOS Radio, Professor Phyllis Stein explains what you need to know about HRV, including what it is, why people measure it, and whether you should measure your own HRV. Tune in for more!


Should You Try to Pay off Sleep Debt on Weekends?

We all occasionally have periods of time in which we don’t get as much sleep as we’d like. When we repeatedly restrict our sleep, we soon suffer from widespread deterioration in metabolic health, brain function, and more.

Fortunately, when people who have been habitually restricting their sleep then extend their sleep, they experience improved health and performance. These sleep extension studies generally involve sleep extension for at least a week, but a more common scenario is for people to try to pay off sleep debt on weekends after restricting their sleep before workdays.

A recent study explored the effects of this kind of weekend recovery sleep on food intake and insulin sensitivity, a key determinant of risk of developing diabetes. The research received lots of attention and sparked much discussion.

So, what did the scientists do, what did they find, and how should we interpret their results?

Read on for more!


Stephan Guyenet vs Gary Taubes on the Joe Rogan Experience – Post-Debate Podcast

Nutrition is perhaps the most emotionally charged of all of the applied sciences. It’s not hard to see why. For one thing, all of us eat, meaning that every single one of us is personally invested in this topic, and we interact with it all the time. We all develop a sense of expertise, in a way that we might not for something a bit more removed from our daily life, like robotics or civil engineering.

In addition, food is arguably the most powerful and primal motivator for animals, ourselves included. And every single one of us has cultivated deep-seated dietary preferences, often established in our formative years. In other words, we are all biased, to varying degrees. It’s hard for us to view our favorite foods in an entirely objective way – even when they are slowly making us sick. To further complicate matters, nutrition is very difficult to research rigorously, and studies are often rife with confounders and apparently contradictory results.

The controversial nature of nutrition science was on full display this Tuesday, when Stephan Guyenet and Gary Taubes appeared together on the Joe Rogan Experience podcast to debate the causes of obesity and type 2 diabetes. Gary and Stephan have very different points of view on this subject, informed by rather different approaches to scientific literature. But as is often the case in debates, there was much that Stephan wanted to say but didn’t get an opportunity to address. That’s why we have welcomed him back to humanOS Radio, to reflect upon his experience on Joe Rogan’s podcast and to further elucidate the causes of obesity and insulin resistance. Click below to check out the interview!


Supplement Industry Trends: Natural Products Expo West 2019

Natural Products Expo West is an annual event in Anaheim in which nearly 3,000 food, drink, and supplement exhibitors come together to showcase their latest products. With the colossal number of exhibitors and more than 86,000 attendees, it can be tough to navigate an expo of this size. Fortunately, however, several members of the humanOS dream team came together to make sense of the bedlam, and in this blog we share the trends that were on show, also highlighting some products that piqued our interests.


Men Who Can Do More Push-ups Have Lower Risk of Cardiovascular Diseases

You probably knew somebody who passed away from coronary heart disease or stroke. Such cardiovascular diseases account for 31% of deaths worldwide – more than anything else – and the frustrating thing is that most of these deaths are preventable by sticking to the fundamental tenets of a healthy lifestyle.

To prevent cardiovascular diseases, it’s useful to have tests that identify people who are at high risk of them. And while assessments of health are becoming ever more sophisticated, we simply don’t know much about how to interpret and act on the outputs of many of the novel tests that have emerged recently.

As I’m often on the lookout for new ways of assessing health, I’m always pleased when people identify effective, simple, and affordable health tests. New research by Professor Stefanos Kales’ team from Harvard School of Public Health shows that the humble push-up may be one such test.

Read on to find out more!