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: hormones

8 Health Reasons to Have Sex (As If You Needed Them)

As promised in last week’s Hunter-Gatherer Fitness post, I’m stirring up the (apparently much awaited) subject of sex – specifically the benefits for physical and mental well-being. Uh, you mean coitus? Yup. Thanks to everyone who responded to the announcement with rousing enthusiasm as well as comments and questions.

What could be more Primal than sex, many of you have suggested. Absolutely right. It was probably one of Grok’s most valued pleasures. (Are people today much different?) For our part, however, we have new freedoms in a manner of speaking. Although we might honor the evolutionary imperative behind our primal appetites with eventual procreation, we’re not beholden to the natural odds with every tryst. As I’ve said many a time, I love studying and learning from the example of Grok and his kin. Nonetheless, I’m a happily modern man in this instance as much as any.

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The Myriad Benefits of Intermittent Fasting

Calorie restriction is all the rage in anti-aging circles. A few mice and worm studies seem to show that drastic reductions in food intake over a long period of time have the effect of prolonging life – although I’m not sure I’d call it living. For one, these animals are actually restricted. There’s no ad libitum access to food. They’d prefer to eat more, but are prevented from doing so. I guarantee you they’re unhappy and, if they could put (cartoonish high-pitched) voice to physiological state, would say they’re starving.

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Dairy and Its Effect on Insulin Secretion (and What It Means for Your Waistline)

Insulin is an old, old hormone. Evolution has preserved its structure across hundreds of millions of years and hundreds of thousands of species. Fish, insects, reptiles, birds, and mammals all secrete insulin with fairly similar amino acid arrangements (insulin from certain species of fish has even been clinically effective in humans), so, clearly, it is a vital hormone. But insulin gets a bad rap in our circles. Why? With metabolic syndrome laying waste to the citizenry and with insulin playing an undeniable role, it’s difficult not to be soured on this hormone.

And yet we need insulin to shuttle all sorts of nutrients into cells, like protein and glycogen into muscles. It’s there for a reason, so to demonize it is misguided. It’s chronically elevated insulin and insulin resistance – you know, the hallmarks of metabolic syndrome – that are the problem. You might have noticed a softening stance on carbohydrates around the paleo and Primal blogosphere. I think it’s simply an acknowledgment that in healthy people with healthy glucose control and healthy insulin responses who engage in glycolytic activity, starch is fine in measured amounts. And if insulin increases to shuttle that starch and protein into the insulin sensitive muscle cells, so be it. That’s why it’s there.

But not everyone (anyone?) lives a perfect Primal existence. And even if you did an understanding of how insulin works and what foods and behaviors affect it’s production should be high priority. Especially for the millions of people immersed in the modern, industrial lifestyle, with deranged metabolisms from years of poor eating habits (i.e. most of us).

Which brings us to dairy and its effect on insulin.

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Sound Cues and Circadian Rhythms

Yesterday, I showed how environmental, behavioral, and social cues act as zeitgebers to human circadian rhythms, and I tried to be as thorough as possible (without outstaying my welcome). I left out one very important environmental cue with the promise of more information today – sound.

I can’t recall exactly where I heard about it, but it was someone’s offhand reference to the notion of the calls of songbirds affecting our circadian rhythms that convinced me I should do a follow-up to the blue light piece from earlier this year. The notion of bird calls affecting us on a deeper level than a regular sound makes some intuitive sense to me, so I did some searching to see if there was anything to it.

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A Different Perspective on Hypothyroidism

Hypothyroid has been covered to death before. I’m particularly fond of The Healthy Skeptic’s coverage – check out Chris Kresser’s ongoing series (possibly before you read on) for some great information on the thyroid. Carnivorous Danny Roddy did a good piece on it last year as well. As such, I won’t be redoing or rehashing an “intro to thyroid.” Instead, I’ll give a brief overview and then discuss why I think some of us may be looking at thyroid “dysfunction” in the wrong light.

The thyroid is a complicated little bugger wielding a lot of influence over the metabolism, and it seems like just about anything has been fingered as a trigger of its dysfunction. Lack of carbs in the diet, too few calories, too much iodine, too little iodine, too many grains, intermittent fasting, excessive cortisol, and multiple other factors have gotten the blame. Unraveling the multiple potential triggers for its dysfunction can be tough. But is dysfunction always the right way to describe a slight reduction in thyroid hormones? I’m not so sure.

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A Primal Primer: Estrogen

The human endocrine system exists in a state of delicate balance. None of its constituents function in a vacuum, and trying to explain every hormonal interrelationship would take volumes, but one statement is fairly safe to make: one hormone affects another. Secreting one often inhibits the next, which in turn sets off an entirely different chain reaction of hormonal secretions, inhibitions, and syntheses. I almost feel like trying to micromanage your entire endocrine system is tedious and counterproductive (and probably impossible to do effectively). I much prefer to simply eat right, exercise smart, get good sleep, normalize stress, and take advantage of simple lifestyle hacks. Still, it doesn’t hurt to understand some of the major hormonal players, especially one as widely maligned by the strength and fitness community as estrogen.

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Testosterone: Not So Manly After All?

Last week’s primer on testosterone garnered a ton of responses, mostly positive, but there appeared to be a bit of confusion regarding testosterone’s role in the female body. Namely, folks seemed to think I was suggesting it played almost no role at all! I tried to be as clear as possible – testosterone is an absolutely vital hormone for women – but I’ll try to be clearer. There’s just that niggling, pervasive stigma of testosterone as the sole hormonal realm of big burly men with bulging muscles, and I guess it’s hard to shake, even for my enlightened readership. Perhaps it’s because we’ve been subject to years of simplistic, substandard health and nutrition advice, black-and-white proclamations that attempt to describe the complex inner workings of the human body with a few sentences.

Fat is bad! Whole grains good! Men make testosterone! Women make estrogen!

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A Primal Primer: Testosterone

If you’ve been reading recently you know I’ve been on a hormone kick recently. That sexy looking molecule to the right and the hormone du jour: testosterone. Testosterone is the principal anabolic and sex hormone in humans, responsible for sexual desire and function, muscular hypertrophy, densification of bones, and hair growth. Compared to females, males famously produce about ten times the amount of testosterone, but females are far more sensitive to its effects. Though testosterone is largely responsible for those traits and characteristics that are considered “masculine” – physical strength, body hair, dominance, and virility – both sexes require it for proper sexual and physical development. In mammals, males secrete it primarily from the testicles (about 95% of the total amount, in fact) and women secrete it from the ovaries. A modicum is produced in the adrenal glands in both sexes.

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Further Adventures with Leptin

I mentioned a few of the working hypotheses for avoiding leptin resistance in my posts last week, including fructose and lectin avoidance, getting adequate nightly sleep, and eating at or above maintenance levels – or at least throwing in periodic carb refeeds – but there’s even more involved in establishing a good relationship with your leptin levels and leptin sensitivity. Depending on your general approach to life, this could be good news or bad news. It’s either more stuff to worry about, or more ways to buttress your health. As I alluded to last week, experimenting with carb refeeding and leptin manipulation within the broader Primal Blueprint eating style is butter on the steak (because “icing on the cake” just won’t do for us Primal folks).

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Primal Advice for Acne Sufferers

Included among last week’s “Ask Me Anything” responses were several requests for a Primal commentary on acne. A lot of people have asked for this kind of post over the years. The fact is, it’s a great question. Acne is a common problem that gives too many people too much grief. Our medical establishment’s prescription for acne generally involves dehydrating the skin into oblivion, sandblasting it with chemicals, or pumping hormones, antibiotics and potentially toxic meds into the patient. (If any of these methods have worked for you, I mean no offense. I just think people deserve better options than these.) Is there a healthier, more Primal method to a clear complexion? In a nutshell, yes. I’m not talking rabbit-in-a-hat trick but a lifestyle approach with natural options that minimize the systemic and external conditions associated with acne. Let’s look at the full picture.

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