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

Testosterone Supplementation: My Primal Take

After I turned 60, a routine checkup showed that I had lower-than-normal free testosterone levels. I hadn’t noticed anything that would have alerted me. No symptoms. No indication. Everything worked well. But it nagged at me. I knew testosterone did much more for a man’s health than just “build muscle”—which I had no real interest in at this point—so I decided to explore TRT, or testosterone replacement therapy.

I did a careful survey of the literature, coming away pleasantly surprised. The evidence was almost uniformly in favor, with the well-constructed studies showing major benefits for TRT. This is TRT, mind you. Not “juicing,” not steroid abuse. Restoration of biologically-appropriate levels of testosterone. Thus began my experiment….

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Is Keto Bad for the Thyroid?

Keto is fantastic, everyone says. It’s a great way to lose weight, improve cognition, and stave off degenerative disease. It may help your performance in the gym and on the track. It could even give Grandpa some respite from Alzheimer’s.

But it’s hell on your thyroid. Right?

Keto detractors and proponents alike often warn that remaining in ketosis will tank your thyroid. The thyroid’s an important gland, exerting major influence over essential systems like fertility, energy, metabolism, body temperature regulation, blood lipids, and general wellness. It controls the metabolic rate of every organ in the body. We want it working well, so this is a major blow to keto—if the criticism holds true. Fortunately, there’s much more to this story.

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Dear Mark: Why are Male Fertility and Testosterone Levels so Low?

For today’s edition of Dear Mark, I’m answering just one question. But it’s a good (well, maybe not good, but certainly important) one: Why is male fertility on the rise and testosterone on the wane? The popular notion is that women flushing birth control pills and peeing estrogen-rich urine into the public water supply are the primary reasons for the sex hormone issues facing men, but I’m not so sure. Let’s explore what else might be causing the problem.

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3 Ways to Regulate Insulin That Have Nothing to Do with Food

Today’s guest post is served by a good friend of Mark’s Daily Apple, Dr. Sarah Ballantyne, PhD, or as you might know her—The Paleo Mom.  

Regulating blood sugar levels is a key feature of any health-promoting diet [15, 20] . High blood sugar levels after eating are a major stimulator of reactive oxygen species (ROS), which are chemically reactive molecules that have important roles in cell signaling (the complex communication between and within cells) and in homeostasis (maintenance of a stable environment inside and outside the cell). But ROS are also potent signals for inflammation and stimulate the production of proinflammatory cytokines (chemical messengers), and also injure cells and tissue. As a result, chronic high blood sugar levels can cause serious damage throughout the body, including to blood vessels and vital organs. This is why diabetes (chronical hyperglycemia) is associated with higher risk of stroke, cardiovascular disease, vision problems, kidney disease, and nerve damage.

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Dear Mark: High T, More Wives? Plus Testosterone for Women and the Best Primal Roux

For today’s edition of Dear Mark, I’m answering three questions from readers. First, I respond to a reader wondering which direction the arrow of casuality points in the married Swahili man/testosterone level study I discussed last week. Are high testosterone levels in polygamous Swahili men a cause or consequence of having more than one wife? Second, what’s the deal with testosterone in women? Do they need it as much as men do? And last but not least, what’s the best gluten-free, Primal-friendly flour to use for making a roux?

Let’s go:

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10 Tips to Boost Your Serotonin

Serotonin is a major regulator of mood and depression risk. These are important, vital roles, to be sure. Your mood describes how you experience and interpret the world. If it’s consistently bad, you’regoing to have a rough time. Yet, serotonin is much more than the “feel-good hormone.” It also influences sexual desire and helps us remember. It’s the precursor to melatonin, the neurotransmitter that allows us to sleep.

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Dear Mark: Hiking and Body Composition, Hiding Liver, Unconventional Testosterone Boosters, Cooked/Cooled/Reheated Potatoes, and Sirtuins

For today’s edition of Dear Mark, I’m answering five questions from readers. First up, why isn’t hiking giving one reader the shifts in body comp they expected? Two, is there actually a way to mask the flavor of liver? Then I discuss a few unconventional testosterone boosters, followed by a brief treatment of the cooked, then cooled, then reheated potato. And finally, are there any dietary activators of sirtuin proteins?

Let’s go:

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Dear Mark: Isometrics and Yoga for Seniors, Plus How Aging Affects Recovery

For today’s edition of Dear Mark, I’m answering a few questions about exercising for seniors. Last week’s post drew a lot of comments, and a few questions about how seniors should train. First, I’ll explore isometrics as an alternative for building strength and power. Can you get away with only trying to move weight? Next, I show how yoga can be an effective strength-builder in older adults. Then, I discuss how aging affects recovery. Many people notice that their recovery time goes way up the older they get. I’ve noticed it myself. Why does it happen?

Let’s go:

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Dear Mark: Do I Need to Eat More, Testosterone Levels, HRV and Carbs

For today’s edition of Dear Mark, I’m answering three reader questions. First, if things are going well on a relatively low-calorie intake, should you just keep on keepin’ on or should you increase food intake to “get ahead” of your needs? Next, what’s the deal with a study showing a high-carb diet is better for testosterone levels than a high-protein one? What does this mean for your Primal way of eating? And finally, can an improvement in heart rate variability after a carb refeed indicate a greater need for carbs?

Let’s go:

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Health Perspective for Every Stage of Life: Part 2

Last week I took up the subject of health through the varying stages of life. What does health mean to us? How should we develop it or live it within the scheme of the different stages we go through as logistical events and developmental maturity shift the focus and parameters of our lives? How do our major milestones challenge our approach to well-being? Let’s pick up that topic again and finish off the discussion. I hope you’ll share your own thoughts on how differing stages of life influenced your thinking about health and what approaches fit the times best for you.

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