This is an updated version of a Dear Mark column from 2012. You can find the original version archived here. The below has been completely updated for 2018. The blank slate hypothesis has fallen. Everyone comes into this world imbued with attributes, characteristics, and predilections that are uniquely theirs. We’re all humans, but we’re a diverse bunch, and that makes it interesting. And though it also makes giving cookie cutter health advice impossible, I just take that as an opportunity to stand out from the crowd and provide actionable advice that genuinely helps real people. A perfect example is biological sex. Anyone who’s lived with the opposite sex, been married, or had kids of different sexes knows that males and females are different—on average. There’s a ton of overlap, don’t get me wrong. Join the Intermittent Fasting Blueprint and get four weeks of intermittent fasting tips and tricks, plus daily Primal fitness, recipe, and lifestyle inspiration to set the foundation for a focused new year. Sign up now! We all need fat, protein, and carbohydrates. We all have the same requirements for sustenance and wellness. We all breathe oxygen, get stronger and fitter when we work out, use the same neurotransmitters, and produce the same hormones. The biological basics are identical. It’s the details that differ. And matter. Take fasting. Stay on track wherever you are! Instantly download your Primal and Keto Guide to Eating Out Fasting As Hormetic Stressor and the Influence of Biological Sex Men and women both need to enter a “fasted” state in order to burn body fat. This should go without saying, but regularly undergoing periods where you’re not inserting calories into your mouth is an absolute requirement for weight loss and basic health, no matter your sex. These periods are called “fasted states,” and they begin as soon as you stop processing the energy from your meal. An “intermittent” fast is an extended period of not eating done for the express purpose of weight loss and other health benefits.  By definition, a fast is a hormetic stressor—a stressful input (no food) that in the right dose triggers an adaptive response that makes us stronger and healthier. Fasting triggers Nrf2, the “hormetic pathway” also triggered by other hormetic stressors like exercise, polyphenols, and radiation. Nrf2 initiates a series of defensive and adaptive mechanisms that help you respond to the stress and buttress your body against future stressors. But with too large a dose, a hormetic stressor can become a plain old stressor—one that overwhelms our defenses and harms us. Making matters more complicated, the size of a hormetic dose is relative. What’s hormetic for me might be stressful for you. Many different variables affect how much of a hormetic stressor a person can tolerate. With fasting, perhaps the most important variable to consider is your biological sex. This really does make intuitive sense. Biology cares most about your fertility. Can you reproduce? Can you produce healthy offspring that survive to do the same? These things come first. And from that perspective, a woman’s … Continue reading Intermittent Fasting for Women: What We Know Now