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...

Tell Me More
Stay Connected

Tag: research analysis

Dear Mark: Increased Red Meat, Reduced Carb, Increased Death?

For today’s edition of Dear Mark, I’m answering three questions. First, what’s the deal with the new Harvard study claiming that eating more red meat increases the death rate? Does it actually prove this? Second, how about the one claiming that reduced carb diets also increase death? Should you worry? And finally, why do I recommend eating locally farmed farmer’s market produce, even if it isn’t organic?

Let’s go:

Read More

Is Keto Cheating Unhealthy?

A couple months ago, a study came out that seemed to show that cheating on your keto diet with a high-carb meal opened you up to severe blood vessel damage. Nine healthy, normal weight adults followed a keto diet (70% fat, 20% protein, 10% carbs). Then they ate a high-carb “cheat meal,” measured their blood sugar, and measured their endothelial microparticles—a marker of damage to the endothelial lining and potential harbinger of impaired vascular function. Their blood sugar went way up, and so did their endothelial microparticle count, leading researchers to conclude that keto dieting makes people more susceptible to hyperglycemia-induced endothelial damage.

So, is keto cheating unhealthy? Let’s take a closer look….

Read More

Does Red Meat Give You Colon Cancer?

Have you heard? There’s a new “red meat will kill you” study. This time, it’s colorectal cancer.

Here’s the press release.

Here’s the full study.

I covered this a couple Sundays ago in “Sunday with Sisson.” If you haven’t signed up for that, I’d recommend it. SWS is where I delve into my habits, practices, and observations, health-related and health-unrelated—stuff you won’t find on the blog. Anyway, I thought I’d expand on my response to that study here today.

Read More

5 Hemp Oil Benefits For Health and Wellness

Have you tried hemp oil? After almost a century of being outlawed, hemp—a form of cannabis with extremely low levels of psychoactive THC—is now legal in the United States. This is big news for people interested in the therapeutic effects of cannabidiol (or CBD) because—while hemp doesn’t contain enough THC, the compound that provides the “high” of cannabis, or any other psychoactive compounds—it does contain cannabidiol (CBD). For years, all anyone talked about when they talked about cannabis was the THC content. Breeders focused on driving THC levels as high as possible and ignored the other compounds. Even pharmaceutical companies interested in the medical applications of cannabis focused on the THC, producing synthetic THC-only drugs that performed poorly compared to the real thing. It turns out that all the other components of cannabis matter, too, and foremost among them is CBD. CBD doesn’t get you high, but it does have big physiological impacts. These days, researchers are exploring CBD as a treatment for epilepsy, anxiety, and insomnia. They’ve uncovered potential anti-inflammatory, anxiolytic, and immunomodulatory properties. And now that it’s quasi legal, hundreds of CBD-rich hemp oil products are appearing on the market. What are the purported benefits of using CBD-rich hemp oil, and what does the evidence say? Although CBD research is growing, it’s still understudied and I expect I’ll have to update this post in the near future with more information. But for now, here’s a rundown of what the research says. 1) Hemp Oil For Anxiety Reduction Anxiety can be crippling. I don’t have generalized social anxiety, but I, like anyone else, know what it feels like to be anxious about something. It happens to everyone. Now imagine feeling that all the time, particularly when it matters most—around other people. The average person doesn’t consider the import and impact of anxiety on a person’s well-being. If CBD can reduce anxiety, that might just be its most important feature. Does it? Before a simulated public speaking event, people with generalized social anxiety disorder were either given 600 mg of CBD or a placebo. Those who received CBD reported less anxiety, reduced cognitive impairment, and more comfort while giving the speech. Seeing as how people without social anxiety disorder claim public speaking as their biggest fear, that CBD helped people with social anxiety disorder give a speech is a huge effect. This appears to be legit. A placebo-controlled trial is nothing to sniff at. 2) Hemp Oil For Sleep A 2017 review provides a nice summary of the effects of CBD on sleep: In insomnia patients, 160 mg/day of CBD increased sleep time and reduced the number of arousals (not that kind) during the night. Lower doses are linked to increased arousals and greater wakefulness. High dose CBD improved sleep; adding THC reduced slow wave sleep. In preliminary research with Parkinson’s patients, CBD reduced REM-related behavioral disorder—which is when you basically act out your dreams as they’re happening. More recently, a large case series (big bunch of case studies done at … Continue reading “5 Hemp Oil Benefits For Health and Wellness”

Read More

The Curious Phenomenon of “Keto Crotch”

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 heat, the fact that I’m paddling and swimming more often now. There’s a whole lot of moisture down there. Perpetual steaminess.

But then I met up with my writing partner and good pal Brad Kearns, who’s been working with me on my upcoming book. Brad lives in Northern California, which is far from hot or humid right now. He’s also a staunch keto guy most of the time, and, well, let’s just say I could smell him before I could see him. We met up at a coffee shop and cleared out everyone in a fifteen foot radius. We sampled a new exogenous ketone product he’s been trying and not one, not two, but three separate individuals approached to inquire if we were salmon fishermen.

Okay, let’s get serious. (And, yes—to address some reader confusion there—the above is pure satire.) Does “keto crotch” really exist? And, if it does, what can you do to prevent it?

Read More

Is Iron the New Cholesterol?

One thing I’ve realized being in this game for so long is that if you’re convinced that meat truly is deadly, you’re not going to stop looking for reasons why. They’ve tried blaming just about every part of meat over the years, including the protein itself, the saturated fat, the cholesterol, the methionine, the char on BBQ, and even the obscure compounds like TMAO or Neu5gc. The latest component of meat they’ve zeroed in on is iron—the essential mineral responsible for energy production and a host of other vital functions.

The experts’ track record with all the other “evil meat components” has many of my readers skeptical, so they asked me to weigh in on iron.

Read More

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:

Read More

A Primal Guide to Prostate Health

Many of you have asked about prostate health in a Primal context. Men are interested because they know men have a decent chance of getting prostate cancer. Women are interested because they’re worried about the men in their lives getting prostate cancer. Today, I’m going to delve deep into the topic, exploring the utility (or lack thereof) of standard testing, the common types of treatment and their potential efficacy, as well as preventive and unconventional ways of reducing your risk and mitigating the danger of prostate cancer.

Let’s go.

Read More

The Pros & Cons of Hormone Replacement Therapy for Primal Women

A Primal woman’s first reaction to the prospect of taking synthetic hormone replacements for menopause? Probably a healthy dose of skepticism. We in the ancestral health community, after all, tend to view pharmaceuticals as a last resort—interventions that are overprescribed by vested interests, create their own set of side effects, and may even do more harm than good. To suggest that we “need” this or that prescription raises our hackles.

Besides, it’s not like menopause is a product of modernity or an aberration our ancestors never experienced; it’s a physiological stage that evolution has protected and selected in humans. It’s perfectly natural. Rather than the debilitating, miserable experience many women report having, menopause should be easier. Graceful, even. But it often isn’t.

Read More

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?

Read More

Join Over 300,000 Subscribers!

Signup and get:

Primal Blueprint Fitness plus 7 other eBooks
7-Day Course on Primal Fundamentals
Special Offers and More!