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: Does Resistant Starch Cause Colon Cancer?

For today’s edition of Dear Mark, I’m handling just one question. I originally planned to answer more reader questions, but it turned into a complex answer that really made me dig deeper into something – butyric acid – I’d assumed was completely benign. I still do, mind you, for the most part. The position has just become more nuanced. Anyway, the question is from a reader who’s just seen a study that seems to implicate butyric acid, the primary short chain fatty acid that resistant starch-eating gut bacteria produce, in colon cancer. Was my ringing endorsement of resistant starch a mistake after all?

Let’s go:

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Dear Mark: Constantly Falling Off the Primal Wagon, Frozen Produce, and A Few More Carbs

For today’s Dear Mark, I answer three questions from readers. First, I give some advice to a reader with a knack for doing a week or two strict Primal and then falling promptly off the wagon into a pile of donuts. How can she make it stick – or should she? Next, I extoll the merits of freezing your freshly homegrown produce rather than rely on under-ripe fruits and vegetables from half a world away. Finally, I discuss what to do when you feel your performance in the gym diminishing.

Let’s go:

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Dear Mark: Sun Exposure and Eyesight; Vasectomies

For today’s edition of Dear Mark, we’ve got a quick two-parter. First, I discuss the pros and cons of ocular sunlight exposure in children (and adults). Should kids leave the house with a pair of wraparound goggles every single time, or are their prepubescent eyes safe without them? If too much sun exposure is bad, is none the best? Then, we cover the pros and cons of getting a vasectomy. Are there real health risks, like increased chances of cancer and/or heart disease? Will you lose functionality down there and experience a drop in testosterone?

Let’s go:

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Dear Mark: 1000 Calories a Day, No Appetite After Exercise, and How to Not Lose Weight

For today’s Dear Mark, I’m taking three questions. First, I comment on Mick Dodge’s (the barefoot forest-living guy with the beard on the NatGeo show) claim that humans can thrive on 1000 calories a day. Is it true? Next, I discuss whether or not people need to worry about a distinct lack of appetite following exercise. Should they listen to their bodies or force down some food? And finally, how should a person who doesn’t want to lose weight go about a Primal way of eating?

Let’s go:

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Dear Mark: Red Meat and Breast Cancer, Net Carbs, and Solutions for Excess, Unavoidable Sun

For today’s Dear Mark, we’ve got a three-parter. First up, I discuss the latest study claiming that red meat will kill us all. Or maybe it’ll be killing roughly half of us all, seeing as how this paper concerns red meat and women’s breast cancer risk. Next, I give my position on the “net carbs” issue. Do we subtract fiber, leave it as is, or do something else entirely? And finally, I talk a lot about the importance of getting enough sunlight. But what happens when getting enough sun isn’t the problem? What can an outdoor worker do about too much sun?

Let’s go:

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Dear Mark: Exercise and Gut Diversity; Pregnancy and Calories

For today’s edition of Dear Mark, we’ve got a two-parter. First up is a discussion of the latest (and only) exercise and gut flora study. It’s been making the rounds and even I gave it a brief mention in yesterday’s Link Love, but today I dig a little deeper. Find out what we can take away from it and apply to our own lives. Then, I cover a series of several questions regarding pregnancy, calories, weight gain, and exercise from a newly pregnant mother-to-be. Even though I’m a man, I offer my perspective and insight.

Let’s go:

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Dear Mark: Young Guy, Low Testosterone; RS for Babies; and Sprints vs Tempo Runs

For today’s edition of Dear Mark, I answer three questions. First up is a young guy with low testosterone. He eats the right foods, does the right exercises, and has lived the right number of years, but he’s saddled with the testosterone of a much older man and wants to know why. Next, I discuss whether resistant starch is suitable or important for infants. The parents are benefiting from it, but does that mean an infant needs it, too? And finally, I explore the value of tempo runs – tough but doable runs maintained at the anaerobic threshold pace – for fat loss. How do they compare to my favorite fat burning exercise – sprints?

Let’s go:

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Dear Mark: Does Dietary Acid/Base Balance Matter?

For today’s Dear Mark, I’m covering just one topic: the relevance of acid/base balance to health. Anyone wading through the morass of Internet diet information has come across the idea than an excess of acidity derived from our diet overloads the body’s ability to balance it with alkalinity. A diverse group invokes it, including strict paleo dieters, vegans grasping for straws to indict meat, and web sites featuring HTML from the 1990s that sell alkalizing water tablets. And because acidity sounds caustic and vaguely negative, lots of people buy into it. So, does it matter?

Let’s go:

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Dear Mark: Are My Vibram FiveFingers Dangerous?

Today, I’m answering one hot-topic question for this week’s Dear Mark. It concerns an issue that’s inspired several dozen emails from readers: the Vibram FiveFingers lawsuit and settlement. If you want to skip ahead to the take home point, it’s that I’m not getting rid of my Vibram FiveFingers anytime soon. Heck, I’m wearing a pair as I type this. I may even be typing with my FiveFinger-clad toes. (It could happen…) If you want my more extensive take on it, read on.

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Dear Mark: Tweaking Sprints for a Stressful Life; Carrie’s Primal Transition

For today’s edition of Dear Mark, I answer one question and Carrie answers another. First up is one from Diane, a (full-time) working mother who’s noticed something interesting about her variable response to sprinting: when she’s relaxed and low-stress or on vacation, sprints lean her out; when she’s working and inundated with stress and responsibilities and concerns, sprints make her retain or even gain body fat. Since she realizes the power of sprinting and doesn’t want to give it up completely, Diane wants a few tips for hacking sprints on a high-stress lifestyle. Next, Carrie gives a quick overview of her transition into the Primal lifestyle and breaks down what Primal living looks like for her these days.

Let’s get into it:

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