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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Tag: dear mark

Dear Mark: Increased Red Meat, Reduced Carb, Increased Death?

For today’s edition of Dear Mark, I’m answering three questions. First, what’s the deal with the new Harvard study claiming that eating more red meat increases the death rate? Does it actually prove this? Second, how about the one claiming that reduced carb diets also increase death? Should you worry? And finally, why do I recommend eating locally farmed farmer’s market produce, even if it isn’t organic?

Let’s go:

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Dear Mark: Electrolytes and Keto Carbs

For today’s edition of Dear Mark, I’m answering questions from the comment sections of the recent posts on daily keto carb limits, within-meal keto carb limits, and electrolytes. I’m addressing questions about alcohol, uniform carb allowances versus personalized, potassium supplementation, salt appetite, salt water, electrolytes after the transition, whether fruits fit in, and why I don’t count above-ground non-starchy vegetables.

Without further ado, let’s go:

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Dear Mark: CBD Edition

For today’s edition of Dear Mark, I’ll be answering your CBD questions from the past few weeks. CBD, or cannabidiol, is exploding in popularity, but there are many unknowns. People have a lot of questions and there aren’t many definitive or comprehensive guides, so today I’ll do my best to make sense of it. We’re all piecing things together based on limited data—which, I suppose, is the fundamental human experience.

Let’s go:

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Dear Mark: What Breaks a Fast Follow-Up

For today’s edition of Dear Mark, I’m answering a round of questions drawn from the comment section of the “What Breaks a Fast” post. You folks had tons of follow-up questions about whether other types of foods or compounds break a fast. Does a teaspoon of honey? Does elevated insulin from BCAAs? Does coconut milk? Does pure prebiotic fiber? What about longer fasts—are they recommended? And how about unsweetened cocoa powder? What explains my ability to predict your questions? Do sausages break a fast? Does liquor? How should you exercise? (For questions on supplements, check out this week’s feature: “What Breaks a Fast: Supplements Edition.”)

Let’s dig right in:

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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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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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Dear Mark: How Does LDL Even Penetrate the Arteries, New Zealand Farmed Salmon, Elevated Ferritin

For today’s edition of Dear Mark, I’m answering three questions. First, can LDL actually infiltrate the arteries, or is there more to the story? Malcolm Kendrick says there’s more to the story, so I dig into some literature to see if they corroborate his position. Second, is New Zealand farmed salmon good to eat? And finally, what should you do about elevated ferritin levels—and why else might they be elevated if not because of your iron?

Let’s go:

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Dear Mark: Iron Followup

Last week’s post on iron levels got a big response and garnered a ton of questions from you guys. Today, I’m going to clarify a few things and answer as many questions as I can. First, do iron and ferritin levels mean different things for men and women? If so, how do those differences manifest? What about premenopausal women vs postmenopausal women? Second, what do we make of the fact that ferritin is also increased in times of inflammation? Is there a way to distinguish between elevated ferritin caused by inflammation and elevated ferritin caused by high iron? Third, is desiccated liver a good option for liver haters? And finally, I share some exciting plague news.

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Dear Mark: How Do Fermented Food and Meat Interact?

For this week’s Dear Mark, I’m answering a question from a reader about a topic I thought I’d covered (so did they) already. A quick look through the archives (hey, I can’t remember absolutely everything I ever wrote) showed that I had not, so here we go. It’s all about whether fermented foods—sauerkrauts, kimchis, pickles, yogurts, and any other food that has been acted upon by probiotic bacteria—make eating meat healthier and more enjoyable. From the start, I suspected that they do, but I had to confirm it in the scientific literature.

Let’s find out:

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Dear Mark: How Do the Hadza Eat So Much Honey? and Happy New Year!

For today’s edition of Dear Mark, I’m answering one eternal question: How do the Hadza tribespeople of Northern Tanzania eat so much honey and maintain their trim figures and pristine metabolic health? Are they eating keto whenever they’re not eating honey? Are they running hill sprints to burn through glycogen stores and improve their insulin sensitivity? Are they trading mongongo nuts for Metformin? Or is there something unique about honey that makes it different than sugar?

But before I get to the question, it’s a brand new year.

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