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: Why are Male Fertility and Testosterone Levels so Low?

For today’s edition of Dear Mark, I’m answering just one question. But it’s a good (well, maybe not good, but certainly important) one: Why is male fertility on the rise and testosterone on the wane? The popular notion is that women flushing birth control pills and peeing estrogen-rich urine into the public water supply are the primary reasons for the sex hormone issues facing men, but I’m not so sure. Let’s explore what else might be causing the problem.

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Dear Mark: Collagen Peptides, Fasting vs Sleeping, Dog Bone Broth, and Pork Broth

For today’s edition of Dear Mark, I’m answering four question. First, are collagen peptides just as effective as bone broth or other collagen sources? Second, how should I choose between IFing or sleeping like a baby using pre-bedtime nutrients that may impede autophagy? Next, I explore whether you should be making dog bone broth (it’s not what you think, so don’t worry about that). And finally, what are some of my favorite pork bone broth recipes?

Let’s go:

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Dear Mark: When Nature is Stressful and How to Use Fish Sauce

For today’s edition of Dear Mark, I’m answering a couple questions from readers. First, is nature always relaxing and blissful? Or are there instances where being in nature is far more stressful than being indoors? Why, and what should we do about it? Second, how do I use fish sauce, and how would a parent use fish sauce to get picky kids to try (and like) new foods?

Let’s go:

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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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Dear Mark: CrossFit and Carb Questions

For today’s edition of Dear Mark, I’m answering questions from the comment section of last Thursday’s post on CrossFit, Primal, and carbs. First, I use a comment from Dave to expand on the idea of earning your carbs and eating the carbs you earn. Second, I discuss the notion of athletes using cyclical low-carb diets. Would their performance suffer? And finally, I go over a few more starchy carb sources allowed on the Primal eating plan that I forgot to mention last time.

Let’s go.

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Dear Mark: HDL, Probiotics for Acne, and Artificial Sweeteneners and Weight Gain

For today’s edition of Dear Mark, I’m answering three questions. First, is HDL all it’s cracked up to be? Is HDL always good? Is it the savior? Or is the story a bit more complicated? Next, what are some good probiotic options for treating acne? Do any exist? And last but not least, what’s the relationship of artificial sweeteners, insulin, appetite, and weight gain?

Let’s go:

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Dear Mark: Ketosis and HIIT, Keto After Menopause, Inuit and Ketosis?

For today’s edition of Dear Mark, I’m answering a few questions from you folks. First, can a person maintain their high intensity interval training while starting a ketogenic diet? Is there anything you should watch out for? Second, is keto a good option for postmenopausal women? Though we don’t have any direct research on the subject, there is hope. And then we discuss the peculiar case of the Inuit and the missing ketones.

Let’s go:

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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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Dear Mark: Keto Follow-Up

For today’s edition of Dear Mark, I’m answering some questions from the comment board of last week’s Definitive Guide to Keto. You folks came up with some great ones. Is counting carbs in non-starchy vegetables still unnecessary on a ketogenic diet? What’s the connection between ketosis and “starvation mode,” and should we be worried? What if you don’t want to lose weight on a ketogenic diet—what modifications should you make? Are you in danger of blowing a breathalyzer test due to ketone metabolites on your breath? Can endurance athletes benefit from keto? Is cyclical ketosis preferable to constant ketosis? Are sugar alcohols ketogenic-friendly?

Let’s go:

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Dear Mark: Too Much Serotonin and Broccoli Sprouts

For today’s edition of Dear Mark, I’m answering two questions from readers. The first is more of a comment, but it brought up a few questions for me to address. Is “more serotonin” always a good thing? Is there such a thing as too much serotonin? And second, what’s the deal with broccoli sprouts? Are they good for us? Has the grungy hippy hawking sprouts next to your meat guy at the farmers market been right all along?

Let’s go:

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