Meet Mark

Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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Category: Weight Loss

The Definitive Guide To Autophagy (and 7 Ways To Induce It)

Biological systems are self-maintaining. They have to be. We don’t have maintenance workers, mechanics, troubleshooters that can “take a look inside” and make sure everything’s running smoothly. Doctors perform a kind of biological maintenance, but even they are working blind from the outside.

No, for life to sustain itself, it has to perform automatic maintenance work on its cells, tissues, organs, and biological processes. One of the most important types of biological maintenance is a process called autophagy.

Autophagy: the word comes from the Greek for “self-eating,” and that’s a very accurate description: Autophagy is when a cell consumes the parts of itself that are damaged or malfunctioning. Lysosomes—members of the innate immune system that also degrade pathogens—degrade the damaged cellular material, making it available for energy and other metabolites.  It’s cellular pruning, and it’s an important part of staving off the worst parts of the aging process.

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The Real Deal On Keto Body Odor

I’m continuing my crusade of keto mythbusting. Recently, there was keto crotch, then keto bloat, and today I’m returning to one of the O.G. myths—keto body odor. Yes, it seems detractors of the keto diet are hell-bent on making you think your body will become a stinky, bloated mess if you dare to drop your carbs below 50 grams per day…but is it true? Here’s the spoiler: Yes, people in online keto diet forums occasionally complain about an unpleasant change in body odor when they first go keto. There is no scientific evidence that it actually happens, nor a clear, compelling explanation for why it would. Moreover, the anecdotal (and it’s all anecdotal) evidence suggests that if it does occur, it is rare and temporary. In other words, the whole idea of keto body odor seems to be exaggerated—shocking, I know.   That said, significant dietary changes can result in other physiological changes that may manifest in a variety of ways. Since nobody wants to be the stinky kid, let’s take this opportunity to look at what might be plausible about keto body odor and what to do if you think you’ve been afflicted.   What Causes Body Odor? First, let’s clarify what’s meant by “body odor.” In the medical literature, the term is used in reference to aromas associated with breath, urine, feces, vaginal secretions, sweat (usually from the axilla, or armpits), and general bodily essence as it were. Because it’s such a broad term, the causes are also extremely varied. For the purposes of this post, I’m going to use the term “body odor” to mean aromas from sweat and general bodily funk, since that’s what’s usually meant by keto body odor. Body odor arises when odorless compounds leave the body through glands in the skin and interact with microbes living on the skin’s surface. The microbes then release chemical compounds—what we actually detect as body odor. Typically, commercial deodorants target both pieces of the equation by using antiperspirants to minimize the excretion of the odor precursors and by creating an unfavorable environment for the microbes living on the skin. There is also a genetic component to how much individuals secrete compounds that cause body odor. Although a huge industry is built around trying to help people mask their natural odors—and suggesting that body odor is always the result of poor hygiene—bodily scents are actually quite important. Just as other animals do, humans use olfactory cues for recognizing kin, making judgments about others’ personality traits and attractiveness, and even for detecting fertility. Although we rarely recognize it, the data suggests that smell probably factors into all our face-to-face social interactions. Body odor can also result from illness. Before the use of sophisticated modern disease detection techniques, doctors were taught to use their sniffers as a diagnostic tool. Even today, smell can be an important clue that an individual is unwell. Often these odors emanate from the breath or urine, but certain infectious and metabolic diseases can be associated with … Continue reading “The Real Deal On Keto Body Odor”

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Dear Mark: Protein Efficiency in Seniors, Earned Carbs, Hardgainer with Limited Time

For this week’s edition of Dear Mark, I’m answering three questions from readers. First, is the reduced protein efficiency in older adults due to inactivity, or is it something inherent to the aging process, or both? Second, how does a person know if they’ve actually “earned” any carbs? Does everyone on a keto diet earn carbs by virtue of exercising, or is there more to it? And finally, how can a hardgainer with a packed schedule all week long and limited gym time maintain what little muscle mass he’s managed to gain?

Let’s find out:

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The Curious Phenomenon of “Keto Crotch”

I have a confession to make: I, Mark Sisson, suffer from keto crotch.

It’s embarrassing, really. I thought maybe it was just the change in climate moving from Malibu to Miami—the humidity, the heat, the fact that I’m paddling and swimming more often now. There’s a whole lot of moisture down there. Perpetual steaminess.

But then I met up with my writing partner and good pal Brad Kearns, who’s been working with me on my upcoming book. Brad lives in Northern California, which is far from hot or humid right now. He’s also a staunch keto guy most of the time, and, well, let’s just say I could smell him before I could see him. We met up at a coffee shop and cleared out everyone in a fifteen foot radius. We sampled a new exogenous ketone product he’s been trying and not one, not two, but three separate individuals approached to inquire if we were salmon fishermen.

Okay, let’s get serious. (And, yes—to address some reader confusion there—the above is pure satire.) Does “keto crotch” really exist? And, if it does, what can you do to prevent it?

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Dear Mark: Fasting, Training, and Growth Hormone; Wear and Tear on the Arteries

For today’s edition of Dear Mark, I’m answering a couple of questions from the comment sections of the last couple weeks. First, it’s been established that fasting and exercise both raise growth hormone. What about fasted exercise—does that have an even stronger effect? And what about continuing to fast after your fasted workout? Then, I discuss the inevitability (or not) of wear and tear on the arteries from blood flow-induced shear stress. Is shear stress “bad,” or do certain factors make it worse?

Let’s dig in.

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How to Accelerate Weight Loss with Fasting

Folks, you know I’m a believer in intermittent fasting for longevity, autophagy, mental clarity, fitness performance, metabolic health, and more. So, when I heard that Dr. Jason Fung, a world expert on fasting, and his team at Pique Tea were putting together a Fasting Tea Challenge this month, I wanted to know more. And I think you will, too. You can check out the details and sign up here. (There’s more info and the sign-up link at the bottom of post, too.)

The Challenge looks to be a great experience for anyone interested in intermittent fasting—including those trying it for the first time and those who have done it before but want to make it more of a regular tool in their healthy lifestyle routine. I’m also thrilled that Dr. Jason Fung has stopped by the blog today to share a bit about fasting for weight loss. Enjoy—and be sure to share any questions you have on the comment board. 

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