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: Vitamin K2 and Microworkouts

For today’s edition of Dear Mark, I’m answering questions about vitamin K2 and microworkouts. The last two posts on both topics garnered a number of good questions. What’s the best dose of vitamin K2? Should statin users taking vitamin K2, since statins inhibit vitamin K2 activity and production? Can vitamin K2 prevent or reverse arterial calcification? Is butter an adequate source of vitamin K2? What about vitamin D—does it synergize with vitamin K2? Regarding microworkouts, what if you can only do a couple pull-ups at once? Should you alternate muscle groups when doing microworkouts? Can microworkouts work with normal gym workouts? How does one do microworkouts in an office?

Let’s find out:

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Dear Mark: What Are the Differences Between Vitamin K2 MK-4 and MK-7?

For today’s edition of Dear Mark, I’m answering a question about the different forms of vitamin K2. Everyone knows the importance of vitamin K2—at least around these parts—but very few understand the differences between the various forms of vitamin K2. What are the respective benefits of vitamin K1, vitamin K2 MK-4, and vitamin MK-7? Where can we find each one?

Let’s find out:
Hi Mark,

Have you ever done an in-depth look at the differences between vitamin K2 MK-4 and MK-7?
No. I’ll do one now.

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Dear Mark: Safe Tick Repellent, Fish Intake on Mediterranean Diet, and Therapeutic Value of Wine

For today’s edition of Dear Mark, I’m answering a few questions from recent comment boards. First, with all the scary tick-related news coming out lately, are there any non-toxic tick repellents that actually work? Are there essential oils that repel and/or kill ticks? Is there a safer way to use insecticides? Next, were the people in the Mediterranean keto study actually eating a kilo of fish on their fish days? And is the wine an important part of the Mediterranean diet? Is the wine therapeutic or just for pleasure?

Let’s find out:

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Dear Mark: Collagen vs Whey Follow-Up

For today’s edition of Dear Mark, I’m answering questions from last week’s Collagen vs Whey post. You guys had a lot of questions, mostly about collagen, and I’m here to answer them. Can collagen help with plantar fasciitis? Should you take collagen and whey together in the same smoothie, or do they cancel each other out? If a person can’t have whey, is there an equivalent protein powder source? Is glycine a good replacement for collagen? What about liquid whey from raw milk—how does it compare to powdered whey? If I wanted to get my glycine from foods, what would I need to eat and how much of it?

Let’s find out:

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Dear Mark: Why No Soy in PK Teriyaki, What Slackline to Buy, and Type 2 Diabetics and Keto

For today’s edition of Dear Mark, I’m answering three questions.

First, why did I leave out soy sauce from the Primal Kitchen® No Soy Teriyaki Sauce? Second, what slackline do I recommend beginners buy? And third, is keto safe for people with type 2 diabetes?

Let’s find out:

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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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