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: Is There No Upper Limit to Endurance Training?

Yesterday, I linked to a study showing that the beneficial effects of high levels of cardiorespiratory fitness—the kind you build with cardio/endurance training, HIIT, and sprints—have no upper limit. At first glance, this study appears to bust the “myth” of chronic cardio and the U-shaped curve of endurance training and prove that the more you train, the longer you’ll live. This appears to run counter to some of my central claims—that too much mid-to-high intensity endurance exercise leads to burnout, health issues, and diminishing returns.

A commenter wrote a great comment that got me wondering:

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Dear Mark: Omega-6 Deficiency and Saw Palmetto

For today’s edition of Dear Mark, I’m answering two questions from readers. First, is it possible to become deficient in omega-6 fats as an adult? What would that even look like, and is there anything that might make omega-6 more important?

Second is a question related to last week’s feature on prostate health. Is saw palmetto an effective supplement for prostate issues? It depends on the issue.

Let’s go:

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Dear Mark: Air-Frying, “Primal” Vegan-ish, Perfect Heath Diet, and Bad Rep or Rap

For today’s edition of Dear Mark, I’m answering four questions. First, is air-frying gentler than deep-frying? Does it produce less acrylamide? Second, what do I think of a reader’s Primal-style plant-based way of eating? It’s actually quite good. Third, why didn’t I mention the Perfect Health Diet in last week’s post on top trending diets? And last, did I make a typo or grammatical error when I wrote “bad rap”?

Let’s find out:

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Dear Mark: PUFA/SFA Swap, Ticks and Meat Allergy, HIIT for Older Men

For today’s edition of Dear Mark, I’m doing three quick topics. First, what are we to make of the studies in which replacing saturated fat and trans-fat with omega-3 and omega-6 polyunsaturated fat seems to reduce heart disease? Second, although red meat is nutrient dense and generally a more interesting option than plain chicken breast, some people have legit red meat allergies (tick-induced or otherwise). What do I think about that and the tick situation in general? And third, is HIIT an effective (and safe) option for middle-aged men?

Let’s go:

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Dear Mark: Diet to Get Lean, Exercise to Get Healthy?

For today’s edition of Dear Mark, I’ll be discussing the role of exercise alone in weight and fat loss. If it seems like I’ve been harping on this same topic for a couple weeks now, it’s only because it’s so important to identify both the mainstream (“You must exercise ten minutes for each Oreo you eat.”) and alternative misconceptions (“Exercise has no effect on body composition.”) about exercise. Exercise—all by itself—actually can help you lose body fat, even if it has less to do with “burning calories” than other factors.

Let’s take a look:

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Dear Mark: Does Physical Activity Affect Obesity Risk?

For today’s edition of Dear Mark, I’m answering one question from a reader. It concerns the effects of physical activity on obesity.

This is an evergreen topic, a constant in the queries I receive. Is exercise necessary for weight loss? Does physical activity improve body weight? Is exercise all about burning calories, or is there something else going on?

Let’s get to it:

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Dear Mark: Pregnenolone

In today’s edition of Dear Mark, I’m talking about pregnenolone, the “master hormone.” Most of the hormones we talk about, like testosterone, estrogen, and cortisol, all have pregnenolone as their precursor hormone. What can happen when pregnenolone goes too low? Can taking pregnenolone solve any problems? Is menopause actually a pregnenolone deficiency?

Let’s find out….

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Dear Mark: Saunas and Finnish Longevity, Saunas and Sperm, What About Ambient Temperature?

For today’s edition of Dear Mark, I’m answering three questions from readers. There was some good feedback after last week’s sauna post, and I want to address a few of the comments. First, does the fact that Finns don’t live as long as some of the other more storied “blue zone” populations despite using saunas negate the utility of the sauna? Second, what should we make of the recent study showing negative effects of sauna on sperm health? And third, isn’t it more “natural” and Primal to seek out smaller ambient temperature fluctuations, rather than brief exposures to extreme temperatures?

Let’s go:

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Dear Mark: Is Coconut Oil Pure Poison?

It appears that we’re well into “outrageous media frenzy over terrible or misleading claims by nutrition scientists” season….

Last week I covered the “low-carb” and mortality study, and for this week’s edition of Dear Mark I’m covering the (latest) coconut oil controversy. A Harvard professor recently launched a dramatic harangue against coconut oil, calling it “pure poison.” Is it true this time? Are we indeed killing ourselves?

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Dear Mark: Choline Supplementing, Too Many Almonds, Keto and Insulin Resistance, and How to Drink

For today’s edition of Dear Mark, I’m responding to four reader comments. First up, if a person can’t eat eggs, doesn’t like liver, but really wants choline, can they just supplement? Second, are a couple handfuls of almonds too much omega-6 for the average person? What if they eat fish? Third, a new study claims to show that keto dieting tanks hepatic insulin sensitivity. What should we make of it? Are we giving ourselves type 2 diabetes by going keto? And fourth, I highlight a great approach to drinking alcohol (and living in general) from one of our readers.

Let’s go:

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