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: Fats

Is Keto Bad for the Thyroid?

Keto is fantastic, everyone says. It’s a great way to lose weight, improve cognition, and stave off degenerative disease. It may help your performance in the gym and on the track. It could even give Grandpa some respite from Alzheimer’s.

But it’s hell on your thyroid. Right?

Keto detractors and proponents alike often warn that remaining in ketosis will tank your thyroid. The thyroid’s an important gland, exerting major influence over essential systems like fertility, energy, metabolism, body temperature regulation, blood lipids, and general wellness. It controls the metabolic rate of every organ in the body. We want it working well, so this is a major blow to keto—if the criticism holds true. Fortunately, there’s much more to this story.

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CrossFit Training: How to Add Mass and Build Strength with Primal

Gaining mass and building strength while CrossFitting should be a breeze. You’re lifting heavy things using compound full-body movements like squats, deadlifts, and presses, providing a potent growth stimulus to your muscles. Yet, many people fall short of their goals, perhaps losing weight and improving performance but failing to really gain any real muscle or strength.

Today, I’m going to explain how going Primal can help you achieve both goals.

First, you must understand the very Primal reality of your body’s hormonal systems and their relation to the environment: Acknowledge that you are an organism whose endocrine system is acutely attuned to the inputs it receives. It’s actively engaged in the world around you, making predictions and taking actions based on your perceptions. If your body thinks it’s living through a famine, it will conserve energy and eliminate wasteful extravagances like big muscles and 2x body weight back squat. If your body thinks it’s living through plentiful times, it will be more liberal with energy and allow the growth of extracurricular tissues, like big muscles. Create an environment of abundance—or even the impression of one—and you will be more likely to gain muscle and strength.

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Dear Mark: Low-Fat Beats “High-Fat”; Prunes for Bone Health

For today’s edition of Dear Mark I’m answering a pair of great questions. First, Vaughn asks me about a recent study where ethnic Chinese participants were placed on several different diets, and those on the “low-carb, high-fat” one actually did worse than those on higher carbs and lower fat. Should you give up your low-carb approach? Then, I explore the bone-strengthening effects of prunes and discuss the Simon and Garfunkel diet.

Let’s go:

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Coconut Oil Is Going to Kill Us All (or Maybe Not…)

I was beginning to rest on my laurels. It had been months since the inbox had flooded with upset readers asking me to address the latest episode of the conventional establishment’s attack on healthy food and living. Until last week, when people starting freaking out about the American Heart Association’s attack on coconut oil. As USAToday put it, “Coconut oil isn’t healthy. It’s never been healthy.”

I was surprised. While I get most of my scientific references from USAToday (the “Works Cited” section of my upcoming keto book is just a single link to USAToday.com) and they’ve never let me down in the past, I didn’t know what to make of their coconut oil claims.

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Is Keto for Everyone?—Cautions, Caveats, and Contraindications

In a few months, I’ll be releasing a book extolling the virtues of a ketogenic diet. I’m currently several months into a ketogenic experiment, which is going well. I just wrote a Definitive Guide explaining why you should consider going keto. I’m on record as stating that everyone should dip into ketosis from time to time. You’d think I’d recommend that everyone go keto. Right?

There are caveats. There are contraindications. There are very good reasons for a person not to go keto, or at least to take a few extra precautions. Today, I’m going to tell you when you should exercise particular care when considering a ketogenic diet.

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Dear Mark: Fat Roundup

Last week, I wrote about my 16 favorite fats. You had questions. For today’s edition of Dear Mark, I’ll answer some of them. First, I explain why my keto salad recipe didn’t include any dense protein. Second, I explain a few options for steaming heavy cream. Third, I tell where I get my mac nuts. Fourth, I discuss whether you should worry about dioxins in pastured eggs. And fifth, I address the question of dietary fat and fatty liver.

Let’s go:

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