The popular story of how low-carb diets work goes something like this: Reducing your carbohydrate...
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
After last week’s post on infrared saunas, people asked some good questions. For today’s edition of Dear Mark, I’m answering a few of them. First up, can infrared saunas harm male fertility? After all, they do penetrate the skin and raise body temperature, which is a no-no for sperm. Next, infrared saunas induce lots of sweating, and sweat contains bioaccumulated toxins like BPA and heavy metals. Can infrared saunas help us shed these toxins? Finally, are infrared-emitting blankets and other “topical” infrared products effective alternatives to infrared saunas?
Last month, I installed an infrared sauna in my house. A company offered it to me to try out, and I was willing to give it a go, knowing a little about them already. It also inspired me to dig into the research—to test it personally but also to see what studies had demonstrated in terms of benefits. I’ll say I’ve been pleased with what I’ve found from both angles.
Over the past few weeks, I’ve been following a new bedtime ritual: a half hour in the sauna, a cold plunge in the pool, bed. The reasoning is that after warming up my tissues in the sauna, I drop them back down to prepare for sleep. So far, it’s working. I wasn’t exactly starting from a deficit—my sleep has been consistently good ever since I changed how I consume alcohol—but I’m really happy with the new setup.
A traditional sauna heats the air around you. An infrared sauna uses infrared light to penetrate your skin and warm you directly without affecting the ambient temperature. This makes them great for home use.
Every former competitive athlete’s worst nightmare is that moment when you lose to a younger person doing the sport you love. When the cocoon of invincibility and superiority you’ve erected around yourself comes crashing down and a piece of your self-identity shatters. It can truly feel like the end.
I know the feeling. Several years ago on a family ski trip, my son challenged me to a downhill snowboard race. We’d been doing these races—and I’d been winning them—ever since he was old enough to board. It was tradition that we race, and that I win. It’s just how it played out.
This time was different. I was a newly minted member of the 6-decades club. He was a young man, fully grown, years of sports under his belt. He smoked me. It wasn’t even close. And suddenly I realized that despite being in the best shape of my life relative to my age, that upper limit was trending down.
Humans are competitive animals. We like a challenge because it compels us to rise to the occasion, prove ourselves, get better at something, or become a bigger version of ourselves. For people, challenges are like hormetic stressors—they often cause suffering and require hard, unpleasant work but provoke a beneficial response that makes us stronger than we were before the challenge.
How does that apply to the challenges I’ve laid out in today’s post, which are all about food, diets, and cooking? Each one unlocks a tangible benefit (eating more vegetables helps you obtain more nutrients, stopping the meal before you’re too full lowers energy intake), but there are also less obvious benefits to meeting a challenge.
Let’s get right to it:
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 you need to follow a vegan diet to maintain the health benefits of long fasts? Second, I give a tip or two for appetite suppression during the fast. Then I discuss my definition of a long fast, the potential effect of fasting on gut bacteria (and whether we should consume prebiotics and probiotics while fasting), the reason why fasting makes some people have short fuses, and whether green tea k0mbucha breaks the fast.
Sometimes it seems like this world is built for extroverts. The most successful politicians, entertainers, and public figures are (or at least come off as) extroverts. One of the “Big 5” personality traits we use to judge and praise people is extraversion (Introversion, falsely assumed as simply the lack of extraversion, doesn’t merit mention.) Certain studies suggest that extroverts make more money than introverts, on average. Extroverts tend to be happier than introverts, regardless of the cultural context. Introverts are more likely to suffer from depression and asthma.
On paper, it seems like extroversion is the clear evolutionary winner. It makes you happier, wealthier, and even healthier (maybe). It’s selected for in many of the most public spheres, like entertainment and politics. So why has introversion been so well preserved? Why do introverts, by most accounts, still comprise at least 25% of the population?