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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Primal Challenge Point: Test Vitamin D Levels

February 08 2018 - "In the winter months, when the sun's rays are not intense enough to generate sufficient vitamin D production (this is the case for three to five months per year for locations in North American—you ...

Dear Mark: Transdermal Magnesium and Vitamin D/B12 Products for a Vegetarian

November 14 2016 - For today's edition of Dear Mark, I'm answering two questions. The first one concerns transdermal magnesium. Does it work? Can magnesium actually permeate the skin and enter circulation? Probably. And...

Dear Mark: Vitamin D for Babes, Ingredient Bait and Switch, and Kettlebellin’ for Strength or Cardio?

June 29 2015 - For today's edition of Dear Mark, we've got a three-parter. First up is a controversial topic: vitamin D supplements for breastfeeding babies. Do they need it? Can they get enough through mother's mil...

Dear Mark: Ornish Strikes Again, Vitamin D from Light Boxes, and Kimchi and Cancer

October 02 2012 - Ah, it's good to be back in the saddle again. The challenge was a lot of fun - don't get me wrong - but ultimately both you guys and I come here for the dispensation of musings and information and wri...

Dear Mark: Hempseed, Too Much Omega-3, and Vitamin D’s Halflife

August 15 2011 - It's a lovely summer morning here in Malibu. The cool sea breeze keeps the coming warmth at bay, for now, and makes me glad for the hot mug of coffee I'm clutching. I've still got a couple hours befor...

Monday Musings: Vitamin D, Toxic Strawberries, New PUFAs Coming Soon

December 06 2010 - A quick look at Google Trends shows a clear, undeniable trend: that of regular folks armed with curiosity, questions, and Internet connections taking their health into their own hands and searching fo...

Vitamin D: Loose Ends

June 15 2010 - Okay, I’ll admit it. I may have spoken out of turn a couple week's ago when I tried to completely cover vitamin D in a mere three posts (Deconstructing Vitamin D, Vitamin D: Sun Exposure, Supplement...

Vitamin D: Confounding Factors

June 03 2010 - Yesterday I recommended 4000 IU of vitamin D each day as a good starting point for most people. Though, it’s difficult – nay, impossible – to provide a perfect, universal prescription for vitami...

Vitamin D: Sun Exposure, Supplementation and Doses

June 02 2010 - From the presence of vitamin D receptors in our cells and vitamin D factories in our epidermis, along with the central role vitamin D plays in calcium metabolism, immunity, and gene expression, it’s...

Deconstructing Vitamin D

June 01 2010 - Before phototropic plants began bending toward sunlight, before jellyfish developed ocelli, the light-sensing organs that allow them to distinguish between up (sunlight) and down, before the bikini-cl...

Dear Mark: Transdermal Magnesium and Vitamin D/B12 Products for a Vegetarian

November 14 2016 - For today's edition of Dear Mark, I'm answering two questions. The first one concerns transdermal magnesium. Does it work? Can magnesium actually permeate the skin and enter circulation? Probably. And...

Dear Mark: Vitamin D for Babes, Ingredient Bait and Switch, and Kettlebellin’ for Strength or Cardio?

June 29 2015 - For today's edition of Dear Mark, we've got a three-parter. First up is a controversial topic: vitamin D supplements for breastfeeding babies. Do they need it? Can they get enough through mother's mil...

Dear Mark: Ornish Strikes Again, Vitamin D from Light Boxes, and Kimchi and Cancer

October 02 2012 - Ah, it's good to be back in the saddle again. The challenge was a lot of fun - don't get me wrong - but ultimately both you guys and I come here for the dispensation of musings and information and wri...

Dear Mark: Hempseed, Too Much Omega-3, and Vitamin D’s Halflife

August 15 2011 - It's a lovely summer morning here in Malibu. The cool sea breeze keeps the coming warmth at bay, for now, and makes me glad for the hot mug of coffee I'm clutching. I've still got a couple hours befor...

Monday Musings: Vitamin D, Toxic Strawberries, New PUFAs Coming Soon

December 06 2010 - A quick look at Google Trends shows a clear, undeniable trend: that of regular folks armed with curiosity, questions, and Internet connections taking their health into their own hands and searching fo...

Vitamin D: Loose Ends

June 15 2010 - Okay, I’ll admit it. I may have spoken out of turn a couple week's ago when I tried to completely cover vitamin D in a mere three posts (Deconstructing Vitamin D, Vitamin D: Sun Exposure, Supplement...

Vitamin D: Confounding Factors

June 03 2010 - Yesterday I recommended 4000 IU of vitamin D each day as a good starting point for most people. Though, it’s difficult – nay, impossible – to provide a perfect, universal prescription for vitami...

Vitamin D: Sun Exposure, Supplementation and Doses

June 02 2010 - From the presence of vitamin D receptors in our cells and vitamin D factories in our epidermis, along with the central role vitamin D plays in calcium metabolism, immunity, and gene expression, it’s...

Deconstructing Vitamin D

June 01 2010 - Before phototropic plants began bending toward sunlight, before jellyfish developed ocelli, the light-sensing organs that allow them to distinguish between up (sunlight) and down, before the bikini-cl...

Vitamin D and RDA for Children

May 31 2008 - It’s probably of little surprise that we take issue with some of the Recommended Daily Allowance values and how they’re often determined. Case in point: New research published in the Journal of Cl...

Dear Mark: Vitamin D for Babes, Ingredient Bait and Switch, and Kettlebellin’ for Strength or Cardio?

June 29 2015 - For today's edition of Dear Mark, we've got a three-parter. First up is a controversial topic: vitamin D supplements for breastfeeding babies. Do they need it? Can they get enough through mother's mil...

Dear Mark: Vitamin K2 and Microworkouts

August 13 2019 - For today's edition of Dear Mark, I'm answering questions about vitamin K2 and microworkouts. The last two posts on both topics garnered a number of good questions. What's the best dose of vitamin K2?...

Does Diet Influence Menopause Timing?

June 13 2019 - Last week, I linked to a story about a popular vegan blogger, author, and influencer who found herself going into menopause at the age of 37 despite doing "everything right." She exercised, she ate ra...

Dear Mark: Potato Diet, Lean Gains, EVOO/Butter/Ghee, Exogenous Ketones, and Early IFing

June 18 2018 - For today's edition of Dear Mark, I'm answering several questions drawn from the comment board of last week's post on fasting vs carb restriction. First, how do I square my recommendations with the su...

Dear Mark: Power Yoga, Pelvic Floor, Keto Reset and Osteoporosis

April 09 2018 - For today's edition of Dear Mark, I'm answering three questions. First, is power yoga—a more "intense" version of yoga that includes strength exercises—a suitable alternative to strength training ...

Women’s Fitness: Should It Change with Age?

April 03 2018 - Generally speaking, the basic Primal Blueprint for fitness and physical activity applies equally to men and women of all ages. Lifting heavy things works in everyone. Sprinting is a fantastic way—fo...

Dear Mark: Improving Exercise Stress Tolerance, Stress and Athletic Performance, My Stress Practices, Non-Negotiable Stress, and Distractions

February 26 2018 - For today's edition of Dear Mark, I'm answering five questions about stress. First, how can someone handle the stress from training five days a week, assuming they don't want to cut back on gym days? ...

Dear Mark: Exercise Rapid Fire, Hunting, Pull-ups, Type 1 Diabetes

January 22 2018 - For today's edition of Dear Mark, I'm answering four questions from readers. The first question is actually 5 questions, so it's closer to 8 questions overall. Good deal. First, I answer 5 questions a...

Dear Mark: Hormone Normalizing Questions

October 02 2017 - For today's edition of Dear Mark, I'm answering questions from last week's hormone normalization post. First I discuss a lack of purpose in the mornings affecting sleep and what to do about it. Next,...

9 Factors That Influence Testosterone Levels

September 06 2017 - In the last several weeks testosterone has come up on a pretty regular basis. I've written about it before, of course, but there's something about the novel elements (e.g. solar irradiation for certa...

Dear Mark: More Embracing Your Wildness

February 19 2018 - Last week's Q&A about cultivating wildness was a lot of fun, but there were some questions I didn't get to in the original post. Today, I'm going to answer some more. From stirring stories of a fa...

Primal Challenge Point: Starting From the “Bottom”

January 23 2018 - In all my years talking with clients and readers, I’ve heard people often say they’re starting from zero, from rock bottom, with no baseline at all. I understand where they were coming from. Every...

Dear Mark: Hormone Normalizing Questions

October 02 2017 - For today's edition of Dear Mark, I'm answering questions from last week's hormone normalization post. First I discuss a lack of purpose in the mornings affecting sleep and what to do about it. Next,...

9 Factors That Influence Testosterone Levels

September 06 2017 - In the last several weeks testosterone has come up on a pretty regular basis. I've written about it before, of course, but there's something about the novel elements (e.g. solar irradiation for certa...

Dear Mark: Fasting Followup

February 27 2017 - For today's edition of Dear Mark, I'm answering questions from the comment section of last week's fasting post. You guys brought up some great points, and I'll be addressing some of them. First up, do...

A Primal Look at Gestational Diabetes

February 14 2017 - Every pregnant woman I've ever known has hated the oral glucose tolerance test. Yet, they still do it. Drinking a tall glass of sickly sweet orange-flavored glucose water on an empty stomach is thorou...

Dear Mark: More of Your Challenge Questions Answered

January 23 2017 - For today's edition of Dear Mark, I'm answering 11 questions. I answer questions about nutrient deficiencies and tremors, breastfeeding on the 21-Day Primal Blueprint Challenge, cheating without appa...

My 7 Favorite Practices for Engineering the Good Life

November 09 2016 - I've never strayed from my basic assertion that the Primal Blueprint is about attaining hedonism congruent with good health. So, when I talk about engineering the good life, I'm not sacrificing healt...

8 Essential Tips for Primal Men

May 25 2016 - Men I know. I am one, after all. Have been for many years. For the most part, I enjoy it. It's worked out really well for me. I don't find it particularly difficult to be a man. Once I dialed in the b...

How to Handle Constructive Criticism as a Primal Advocate

March 17 2016 - It’s a role that’s probably more often thrust upon us than one we individually choose—that of Primal advocate. There we are minding our own healthy business, and somebody’s question or comment...

Primal Challenge Point: Test Vitamin D Levels

February 08 2018 - "In the winter months, when the sun's rays are not intense enough to generate sufficient vitamin D production (this is the case for three to five months per year for locations in North American—you ...

Dear Mark: Vitamin D for Babes, Ingredient Bait and Switch, and Kettlebellin’ for Strength or Cardio?

June 29 2015 - For today's edition of Dear Mark, we've got a three-parter. First up is a controversial topic: vitamin D supplements for breastfeeding babies. Do they need it? Can they get enough through mother's mil...

Dear Mark: Ornish Strikes Again, Vitamin D from Light Boxes, and Kimchi and Cancer

October 02 2012 - Ah, it's good to be back in the saddle again. The challenge was a lot of fun - don't get me wrong - but ultimately both you guys and I come here for the dispensation of musings and information and wri...

Monday Musings: Vitamin D, Toxic Strawberries, New PUFAs Coming Soon

December 06 2010 - A quick look at Google Trends shows a clear, undeniable trend: that of regular folks armed with curiosity, questions, and Internet connections taking their health into their own hands and searching fo...

Vitamin D: Loose Ends

June 15 2010 - Okay, I’ll admit it. I may have spoken out of turn a couple week's ago when I tried to completely cover vitamin D in a mere three posts (Deconstructing Vitamin D, Vitamin D: Sun Exposure, Supplement...

Vitamin D: Confounding Factors

June 03 2010 - Yesterday I recommended 4000 IU of vitamin D each day as a good starting point for most people. Though, it’s difficult – nay, impossible – to provide a perfect, universal prescription for vitami...

Vitamin D: Sun Exposure, Supplementation and Doses

June 02 2010 - From the presence of vitamin D receptors in our cells and vitamin D factories in our epidermis, along with the central role vitamin D plays in calcium metabolism, immunity, and gene expression, it’s...

Deconstructing Vitamin D

June 01 2010 - Before phototropic plants began bending toward sunlight, before jellyfish developed ocelli, the light-sensing organs that allow them to distinguish between up (sunlight) and down, before the bikini-cl...

Vitamin D and RDA for Children

May 31 2008 - It’s probably of little surprise that we take issue with some of the Recommended Daily Allowance values and how they’re often determined. Case in point: New research published in the Journal of Cl...

Does Diet Influence Menopause Timing?

June 13 2019 - Last week, I linked to a story about a popular vegan blogger, author, and influencer who found herself going into menopause at the age of 37 despite doing "everything right." She exercised, she ate ra...

Primal Egg Coffee: The Best Part of Waking Up?

July 24 2013 - Bulletproof coffee has taken the paleo world by storm. Not me, though. Don't get me wrong. I'm all for people dropping grass-fed butter and coconut/MCT oil into their high-quality coffee, blending ...

The Perfect Primal Omelet

September 25 2010 - Breakfast, lunch, dinner, snack time. Hard boiled, scrambled, poached, fried. We’ll take eggs any time of day, any way you want to cook ‘em. But if we had our choice, the omelet just might be our ...

2 Meat, 2 Pepper Chili

March 24 2019 - Thanks to the good folks at Paleohacks for today's recipe. This rich keto chili is made with two types of beef and slow cooked in bone broth for stick-to-your-ribs heartiness. This rich and simple ...

Low-Carb & Keto Chayote “Apple” Crisp

March 10 2019 - Chayote squash is having its day in the sun as of late, but it's been used for centuries in Latin American cooking and baking. The chayote squash (also known as mirliton squash) is a mild-tasting, rel...

Roasted Bone Marrow with Rosemary and Garlic

October 13 2018 - Bone marrow is an important supplemental food that’s easy to love—if you love fatty, savory treats, that is. And bone marrow is a treat, with its over-the-top richness, meaty flavor and fatty, cre...

Midweek Quick Cooking: Chipotle Lime Avocado Bacon Dip

March 07 2018 - Looking for some inspiration to eat more vegetables? Or maybe you just need a healthy, filling go-to snack or lunch side? This dip is it. With the kick of Primal Kitchen® Chipotle Lime Mayo, crudite ...

Clams in Creamy Mustard Broth

February 17 2018 - It’s easy to forget that a pot of steamed clams (or mussels) makes a perfect weeknight dinner. It’s one of the easiest seafood meals to cook, and also one of the healthiest. Shellfish cook in 5 mi...

Dark Chocolate and Hazelnut Hearts

February 14 2018 - Show yourself some love on Valentine’s Day by indulging in these heart-shaped dark chocolate candies. These treats are truly irresistible, with intense bittersweet flavor and a smooth, creamy textur...

Creamy Broccoli Spinach Soup

December 02 2017 - Broccoli and Spinach Soup sounds like it’s going to taste a little too healthy. Rest assured, however.... Although this soup is packed with vitamins, minerals and antioxidants from the broccoli and ...

Curried Pork Frittata

November 04 2017 - This curried pork frittata is a high-protein and high-fat meal that’s perfect for brunch or dinner. It’s a frittata, basically, with added flavor from coconut milk (or whole cream), ground pork, c...

Keto Was a New Way Of Life

March 04 2019 - It's Monday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark's Da...

Focusing On My Gut Health Has Transformed My Life

December 17 2018 - It's Monday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark's Da...

My Family’s Primal Living Achievements Empowered Me

August 24 2018 - It's Friday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark's Da...

I Feel Better Than I Ever Did In My Life

August 03 2018 - It's Friday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark's Da...

Success Story Follow-Up: Each Modification Has Built on What I Had Established

July 28 2017 - It’s Friday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark’...

Finally Getting Lean and Feeling Excellent!

April 21 2017 - It’s Friday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark’...

Paleo Thyroid Solution Success Story: Cara Haun

September 16 2016 - It’s Friday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. This week's featured testimonial is one of many success stories spurred by Primal Blu...

Going Primal Will Change Your Life for the Better!

February 20 2015 - It’s Friday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark’...

Hope Has Been Restored: My 21-Day Challenge Results

February 06 2015 - It’s Friday, everyone! And that means another Primal Blueprint Real Life Story from a Mark's Daily Apple reader. If you have your own success story and would like to share it with me and the Mark’...

What Breaks a Fast: Supplement Edition

April 17 2019 - Last week, I explored the impact of all the various foods, beverages, and food-like substances people consume while fasting—and hoping to maintain a functionally fasted state in the post, "The Defin...

The Curious Phenomenon of “Keto Crotch”

March 12 2019 - I have a confession to make: I, Mark Sisson, suffer from keto crotch. It's embarrassing, really. I thought maybe it was just the change in climate moving from Malibu to Miami—the humidity, the he...

Dear Mark: Potato Diet, Lean Gains, EVOO/Butter/Ghee, Exogenous Ketones, and Early IFing

June 18 2018 - For today's edition of Dear Mark, I'm answering several questions drawn from the comment board of last week's post on fasting vs carb restriction. First, how do I square my recommendations with the su...

Dear Mark: More of Your Challenge Questions Answered

January 23 2017 - For today's edition of Dear Mark, I'm answering 11 questions. I answer questions about nutrient deficiencies and tremors, breastfeeding on the 21-Day Primal Blueprint Challenge, cheating without appa...

Dear Mark: Your Challenge Questions Answered

January 16 2017 - Last week, you guys asked me a ton of questions as part of a contest. Today, I'm going to answer an initial batch. (If you don't see yours, check back on Mondays to come when I'll take up others.) Fir...

How Language Affects Your Fitness and Weight Loss Practice

July 28 2016 - Every day we’re barraged by “good ideas”—all the things we should be doing with our lives and could start doing today if we really cared enough. Too much advice can overwhelm us, and, more imp...

8 Essential Tips for Primal Men

May 25 2016 - Men I know. I am one, after all. Have been for many years. For the most part, I enjoy it. It's worked out really well for me. I don't find it particularly difficult to be a man. Once I dialed in the b...

12 Surprising Things You Can Do With Avocado Oil

April 13 2016 - If it were up to me, I'd have a steady supply of perfect, ripe avocados on hand. They'd have no blemishes, no bruising, no weird soft spots, no stringy veins running through. Every avocado would be ri...

The Definitive Guide to Using Your Recent Ancestry to Determine Your Optimal Diet

January 06 2016 - Go back 160,000 years and we all share a common ancestor: The emergence of the first Homo sapiens in East Africa. Since then, humans have spread across every environment imaginable and adapted to tho...

Dear Mark: Foods for a One-Year-Old, Vegan to Primal, and Low-Carb Failing Fibromyalgia

December 07 2015 - For today's edition of Dear Mark, I'm answering three reader questions. The first comes from Chris, who's a little worried his one-year-old isn't eating a wide enough variety of foods. As it turns out...

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