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: Diet & Nutrition

Dear Mark: Testosterone and Marriage, Dangerous Gluten-Free Diets

For today’s edition of Dear Mark, I’m answering two questions from readers. The first one concerns the reduction in testosterone men experience with marriage. Is it a feature? A flaw? Is it inevitable? After that, I get into a pair of new studies that question the safety of gluten-free diets in the absence of celiac disease. Is your gluten-free diet going to kill you?

Let’s go:

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Oral Health: What You Eat (and Don’t Eat) Counts

With conventional wisdom’s take on oral care, we’re left with a pretty superficial understanding of oral health. What if, for instance, cavities imply more than bad brushing habits? What if we changed the entire template from one focused on cosmetic and sensory criteria to an understanding founded on whole health principles? Answer: we’d be much closer to the truth.

Consider this. A recent study involving over 37,000 dental patients found that “patient-reported general health and risk factors were negatively associated with an overall composite oral health score,” with study authors noting their results supporting a “growing body of evidence linking oral and systemic health.” As for the particular health connections, you’d be surprised at the span of influence: cardiovascular disease, pneumonia, diabetes, even pregnancy issues.

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The Language of Microbial Culture: Explaining Prebiotics, Probiotics, Synbiotics and Postbiotics

It’s no secret that it’s one of my favorite subjects—the burgeoning field of human gastrointestinal microbiology. I know…it’s easy to get caught up in the comparative excitement of it all.

The microbiota is familiar territory to most Primal types, but with time and research, we come to understand the nuances of the terrain a little better. New terms pop up. Novel discoveries grab our attention. Promising connections become apparent. It feels like a good day to go over a bit of the latest—to provide a little refresher for those who’ve joined us recently and most of all to offer some additional perspective on what we’re learning as studies branch into new depths. 

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Dear Mark: Superfoods, Plants for Pollution, Raw Liver Danger, and Irradiated ‘tsticles

For today’s edition of Dear Mark, I’m addressing four questions and comments from readers. First up, do I subscribe to the idea of superfoods? If so, what do I like? If no, what do I consider “super”? Next, we know that plants—house plants, garden plants, trees—can absorb pollution and release stress-lowering odors. Is there an optimal arrangement of flora to achieve these goals? After that, I address a reader comment about the dangers of eating raw liver, followed by an intrepid reader who found the reference for the sunbathing testicle study from last week.

Let’s go:

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5 Unconventional Ways to Extend Your Life

I’ve written about extending your life by slowing down the apparent passage of time. I’ve written about some interesting predictors—but not necessarily causes—of longevity, and the common characteristics of centenarians. Today, I’m going to describe several unconventional causal means of extending your life.

I’m talking about cold, hard days, weeks, and months. Ticks on a clock. Objective measurements of time. Not just the perception of time, although that matters too.

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Dear Mark: Hiking and Body Composition, Hiding Liver, Unconventional Testosterone Boosters, Cooked/Cooled/Reheated Potatoes, and Sirtuins

For today’s edition of Dear Mark, I’m answering five questions from readers. First up, why isn’t hiking giving one reader the shifts in body comp they expected? Two, is there actually a way to mask the flavor of liver? Then I discuss a few unconventional testosterone boosters, followed by a brief treatment of the cooked, then cooled, then reheated potato. And finally, are there any dietary activators of sirtuin proteins?

Let’s go:

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