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: Keto

Dear Mark: Ketosis and Testosterone, Dehydration Hormesis, and Isomalto-Oligosaccharides

For today’s edition of Dear Mark, I’m answering three questions. The first one concerns a potentially combative and controversial topic: ketogenic diets. What’s the deal with their effect on testosterone? You can find keto anecdotes across the web both inspiring and flaccid, but what, if anything, does the science say? Next, might there be a way to derive beneficial hormetic effects from acute bouts of dehydration? It seems like every other stressor can actually make a person stronger, so perhaps an otherwise wholly negative one like dehydration might as well. And finally, is the prebiotic fiber known as isomalto-oligosaccharide safe and/or good to eat?

Let’s go:

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Dear Mark: High HbA1c with Low Blood Sugar; Muscle Glycogen: Is It Local?; and Ketogenic Mosquito Repellant

For today’s edition of Dear Mark, we’ve got a three-parter. First, what could possibly explain an ardent and otherwise healthy low-carber with stellar postprandial (i.e. after a meal) blood sugar levels showing up with an HbA1c reading indicative of pre-diabetes? Who’s messing up — the test or Nancy herself? Next, that pastured chicken you’re about to eat may very well be local, but what about the glycogen in your quads? Is a muscle’s glycogen usable only by that muscle, or can it be shipped to nearby muscles as well? And finally, a reader reports suddenly becoming unattractive to mosquitoes upon adopting a low-carb diet and bouncing in and out of ketosis. Is he imagining things or is there a potential mechanism at play?

Let’s go:

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Dear Mark: French Press Coffee, Mid-Oleic Sunflower Oil, Peanuts, and a Keto Success Story

For today’s edition of Dear Mark, I’m answering three questions and sharing a quick, but awesome story from a reader. First, are French press, Turkish, and other unfiltered boiled coffee preparations unhealthy due to the presence of coffee oils in the finished product? They may raise LDL, which gets the conventional health experts hot and bothered, but there are other effects, too. Second, high-oleic sunflower oil was given the go-ahead in a previous post. What’s the story with mid-oleic sunflower oil? Third, with the recent study indicating that peanut/tree nut eaters enjoy improved mortality from all causes, should we take peanuts and most importantly peanut butter off the “no-go” list? And finally, a long term keto success story briefly mentioned in last week’s post writes in.

Let’s go:

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Dear Mark: Peripheral Neuropathy, Primal Compromises for Love, and Carbs in Ketosis

For this week’s edition of Dear Mark, I’m answering three questions. First up, what could be causing a reader’s peripheral neuropathy? Could it be gluten, B12 and/or B6 deficiency, diabetes, or inadequate vitamin D? The second question concerns homemade pasta, a beautiful woman, and a dilemma: do you indulge in the former to make the latter happy? My answer may surprise you, or it may not. I’m not sure. But I think you’ll find it helpful regardless. And finally, can carbs and ketosis co-exist? They certainly can, but there’s a little trick to make it work.

Let’s go:

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Dear Mark: Fat Gain on a Ketogenic Diet; Dandruff and an Itchy Scalp

For today’s edition of Dear Mark, we’ve got a two-parter. First up, I respond to a comment from last week’s Weekend Link Love concerning fat gain and lean mass loss in taekwondo athletes on a ketogenic diet. Did the athletes actually get fatter and lose muscle on their diet, even as performance improved? After that, I discuss what to do about dandruff and an itchy scalp. There may be no silver bullet against the common malady known as dandruff, but there are a few things you can try and one in particular that looks quite promising.

Let’s go:

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Dear Mark: Workout Break, Raw Milk, Banana Breakfast, Ketosis in Breastfeeding, and Bikram Yoga

In this edition of Dear Mark, I provide rapid fire answers to five of your questions. First, I discuss another situation where the deload week(s) make(s) sense and may even have to be extended: when exercise starts taking away from the quality of your life. Next I explain why for some people raw milk is a highly-coveted food, and then whether or not a banana should be breakfast. After that, I discuss the potential impact of ketosis on breastfeeding. Finally, I discuss the benefits and potential downsides of Bikram yoga.

Let’s go:

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Dear Mark: How Much Glucose Does Your Brain Really Need?

We now know that the oft-repeated “your brain only runs on glucose!” is wrong. I’ve mentioned it before, and anyone who’s taken the time to get fat-adapted on a low-carb Primal eating plan intuitively knows that your brain doesn’t need piles of glucose to work, because, well, they’re using their brain to read this sentence. Obviously, you eventually adapt and find you have sufficient (if not much improved) cognition without all those carbs. That said, some glucose is required, and that’s where people get tripped up. “Glucose is required” sounds an awful lot like “your brain only uses glucose” which usually leads to “you need lots of carbs to provide that glucose.” And that’s the question today’s edition of “Dear Mark” finds itself attempting to answer: how much glucose is required?

Let’s get to it.

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