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: Hype

What’s TMAO, and What Does It Have to Do With My Health?

With the last few weeks’ definitive guide and follow-up on fish, a reader asked me about trimethylamine N-oxide, or TMAO. What is it?

TMAO is the latest justification given for why eating meat just has to be bad for you. Saturated fat didn’t take. Animal protein didn’t work. Iron was a dud. IGF-1 hasn’t panned out. Methionine isn’t enough. So now they’re using TMAO to convince you not to eat that steak.

How’s it supposed to work?

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10 Keto Hacks to Try…Or Not

When I say “hack” or “biohack,” what does that call to mind for you? Taking 20 supplements per day, shining special lights into your ears, stem cell injections? Simpler things like wearing blue light blocking glasses or turning your shower to cold for 30 seconds?

The term has become ubiquitous in modern parlance, to the point where its meaning has become blurred. On the one hand, hacking can be about optimizing—taking your health and fitness to the next level once you have the basics dialed in, or adopting strategies aimed at living well over 100. On the other hand, a hack can also be a shortcut or trick designed to reap certain benefits without putting in the usual work. (Whether that’s a clever maneuver or a form of “cheating” depends on the context and whom you ask.)

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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:

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CBD For Performance: What We Know So Far

I left the pro athlete world a long time ago. I no longer compete. I don’t train with the intensity and volume it’d take to win races. But I do pay attention to what’s going on in that world, and I still have a lot of friends who never left it. Developments there often foreshadow developments in the rest of the health world. And after things like keto, MCT oil/ketones, and collagen, the performance hack that’s blowing up among elite athletes is CBD oil. Almost everyone I talk to who puts in serious training and competing time (in a variety of sports and pursuits) is dabbling with CBD.

What are they using it for?

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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.

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Dry Fasting: Is It Worth It?

Today’s post is about dry fasting. I’ve covered plenty of other aspects of intermittent fasting, including recommendations around longer fasts, but lately I’ve gotten enough questions about this particular angle that I thought I’d address it.

Dry fasting is going without both food and fluid. That means no coffee, no tea, no broth, and no water or liquid of any kind (except the saliva you manage to produce). It’s an extreme type of fast whose fans and practitioners are adamant that it can resolve serious health issues. But does it? Is it safe? And what kind of research is available on it?

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Keto and the Menstrual Cycle: Is There Reason To Worry?

It seems every “keto for women” forum abounds with stories about menstrual cycles gone wild in the first few months of keto. Irregular cycles, breakthrough bleeding, and periods lasting much longer than normal are common complaints. Sometimes these stories are cited as evidence that keto isn’t good for women, at least not premenopausal women, and that we need carbs for healthy hormones. Yet, many women don’t notice any changes in their menstrual cycles at all, while others report improvement in PMS symptoms and cycle regularity from the get-go.

What gives? Why do some women’s cycles apparently become wacky when they start keto, while others feel like keto is the key to period bliss? Can keto “mess up” the menstrual cycle?

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The Real Deal On Keto Body Odor

I’m continuing my crusade of keto mythbusting. Recently, there was keto crotch, then keto bloat, and today I’m returning to one of the O.G. myths—keto body odor. Yes, it seems detractors of the keto diet are hell-bent on making you think your body will become a stinky, bloated mess if you dare to drop your carbs below 50 grams per day…but is it true? Here’s the spoiler: Yes, people in online keto diet forums occasionally complain about an unpleasant change in body odor when they first go keto. There is no scientific evidence that it actually happens, nor a clear, compelling explanation for why it would. Moreover, the anecdotal (and it’s all anecdotal) evidence suggests that if it does occur, it is rare and temporary. In other words, the whole idea of keto body odor seems to be exaggerated—shocking, I know.   That said, significant dietary changes can result in other physiological changes that may manifest in a variety of ways. Since nobody wants to be the stinky kid, let’s take this opportunity to look at what might be plausible about keto body odor and what to do if you think you’ve been afflicted.   What Causes Body Odor? First, let’s clarify what’s meant by “body odor.” In the medical literature, the term is used in reference to aromas associated with breath, urine, feces, vaginal secretions, sweat (usually from the axilla, or armpits), and general bodily essence as it were. Because it’s such a broad term, the causes are also extremely varied. For the purposes of this post, I’m going to use the term “body odor” to mean aromas from sweat and general bodily funk, since that’s what’s usually meant by keto body odor. Body odor arises when odorless compounds leave the body through glands in the skin and interact with microbes living on the skin’s surface. The microbes then release chemical compounds—what we actually detect as body odor. Typically, commercial deodorants target both pieces of the equation by using antiperspirants to minimize the excretion of the odor precursors and by creating an unfavorable environment for the microbes living on the skin. There is also a genetic component to how much individuals secrete compounds that cause body odor. Although a huge industry is built around trying to help people mask their natural odors—and suggesting that body odor is always the result of poor hygiene—bodily scents are actually quite important. Just as other animals do, humans use olfactory cues for recognizing kin, making judgments about others’ personality traits and attractiveness, and even for detecting fertility. Although we rarely recognize it, the data suggests that smell probably factors into all our face-to-face social interactions. Body odor can also result from illness. Before the use of sophisticated modern disease detection techniques, doctors were taught to use their sniffers as a diagnostic tool. Even today, smell can be an important clue that an individual is unwell. Often these odors emanate from the breath or urine, but certain infectious and metabolic diseases can be associated with … Continue reading “The Real Deal On Keto Body Odor”

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Keto Bloat: Separating Fact from Fiction

Move over, keto crotch. There’s a new fear-mongering anti-keto media blitz forming: keto bloat.

According to the “good scientists” of the Kellogg company food lab, an unprecedented number of young people are walking around with bloated guts and colons packed to the brim with impacted fecal matter, and it’s all because they’ve embraced ketogenic diets and “forsaken” fiber.

If this sounds like nonsense, that’s because it is.

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What’s the Pegan Diet? (And How Does It Compare To Primal?)

Because people don’t have enough diets to choose from already, there’s a new one on the scene: the Pegan diet. Actually it’s not that new—Dr. Mark Hyman started writing about it back in 2014, but it’s gained traction since he published his latest book last year, Food: What the Heck Should I Eat? According to Hyman, Pegan is a somewhat tongue-in-cheek play on the fact that it’s not quite Paleo and it’s not really vegan, hence Pegan. It claims to combine the best of both diets, namely a focus on eating lots of vegetables, as well as an emphasis on sustainable agriculture and ethical and ecologically sound animal farming. Setting aside the obvious issue that it’s 100% possible to be a vegan who eats few to no vegetables, or to be a paleo dieter who cares naught about the environment, Pegan is touted as being easier to stick to than either vegan or paleo (presumably because Pegan allows for consumption of foods not allowed on either). Frankly, trying to frame it as a bridge between the two hasn’t proved to be a seamless, happy compromise based on social media conversation, but that’s probably of little surprise to anyone here. I’ve had some readers ask me about the merits of Pegan and whether it offers any particular advantages over paleo/Primal, and I’m taking up that question today. (Note that I’m only focusing on the Pegan diet proposed by Dr. Hyman, not the “Pegan 365” diet offered by Dr. Oz. The latter isn’t paleo at all, allowing whole grain bread and pasta, corn, tofu, and a weekly “cheat day.” You can imagine my response to this version.) Defining the Pegan Diet These are the basic tenets of the Pegan diet in a nutshell: Focus on sourcing high-quality food – Prioritize organically grown and pesticide-free produce as well as meat, eggs, and fats from pasture-raised and grass-fed animals and finally sustainably harvested seafood. Choose seafood with the lowest possible mercury content. Buy local when you can. Avoid CAFO meats and foods containing chemical additives. Eliminate processed modern food-like substances and franken-fats – Processed carbohydrates have a high glycemic load and lead to excessive insulin production. Refined vegetable and seed oils such as canola and sunflower are pro-inflammatory. Avoid all such products. Go gluten-free – Even if you don’t have celiac disease or an obvious gluten sensitivity, modern wheat is still a frankenfood, and gluten can damage the gut. Occasional consumption of heirloom wheat (e.g., einkorn) is ok if you tolerate it. Go dairy-free – Dairy is problematic for most people and is best avoided. If you do decide to include some dairy, consider choosing goat and sheep milk products instead of cow. Grass-fed butter and ghee are acceptable. Make vegetables the centerpiece of your diet – Vegetables (mostly non-starchy) should comprise 75% of your diet. Enjoy healthy fats – Focus on omega-3s, as from small, oily fish. Eat plenty of healthy fats from grass-fed and pastured meats and whole eggs, nuts and seeds, … Continue reading “What’s the Pegan Diet? (And How Does It Compare To Primal?)”

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