A Newsletter For Men. And For The Women Who Love Them.

Morning!

[Before we get into the grit of this week’s edition, we want to announce a change to the 8% schedule. From now, newsletter editions will be sent out to your inboxes every Wednesday (same time). With that out of the way, enjoy this week’s edition!]

Last week, we dove into the topic of women’s fertility, breaking down the often-overlooked connections between nutrition, hormones, and reproductive health. This week, we’re turning the lens the other way, because fertility and health are very much a two-player game.

We’re diving into something that’s long overdue: men’s health. Yes, that topic. The one that gets quietly avoided like the kale in a breakfast buffet. But whether you’re a man yourself or someone who loves one, this conversation matters, and not just once something starts hurting.

The reality is that declining energy, low testosterone, mood swings, trouble sleeping, and infertility are not “just aging” or “just stress.” And they’re not inevitable. The problem lies in that society still frames health checkups like they’re optional. Add a healthy dash of “I’m fine,” and we’ve got a culture of guys powering through until things get worse.

This isn’t just about doctor visits, it’s about noticing when something’s off and understanding why. Like chronic tiredness that seems random, until you realize you haven’t seen the sun in five days and your vitamin D levels are subterranean. So, let’s break it down.

CORE

Hormone Health & Testosterone

If testosterone had a stock ticker, it would be a red arrow pointing straight down. According to Dr. Thomas Travison from the New England Research Institute, average testosterone levels have been falling by about 1% a year, a trend that's persisted for decades. Some studies estimate that 10% to 40% of men may now be testosterone deficient. You might be wondering why the estimates vary so much. That’s what happens when a significant number of men don’t go get lab reports done. (Sorry, fellas, you know it’s true.)

Low testosterone affects energy, focus, sleep, mood, muscle strength, bone density, fat storage, and reproductive health. In other words: it’s kind of a big deal.

What does Testosterone do? 

Testosterone is the hormone behind muscle strength, energy, libido, and even mental clarity. It supports red blood cell production, keeps bones strong, and helps regulate mood and memory. When levels drop, energy crashes, strength fades, and fertility can take a hit. In short, it’s a key player in men’s overall health.

Why would Testosterone be so low?

Good question. The short answer? No one’s entirely sure. But here are the most likely culprits:

Excess body fat. Fat cells produce estrogen. Estrogen tells the body to dial down testosterone. Combine that with the fact that nearly three-quarters of American men are overweight, and the math starts to make sense.

 Lack of exercise. Not moving won’t tank testosterone, but resistance training and moderate-to-intense workouts can increase it. Skip the gym long enough, and you miss out on a natural, legal boost.

Low vitamin D is linked to lower testosterone levels. It activates the enzymes that are required for the production of testosterone. Since over 90% of adults have suboptimal vitamin D levels, and 42% fall below the clinical threshold for deficiency. This can mean that testosterone production is not efficient and can lead to deficiency.

Low Magnesium. Magnesium plays a behind-the-scenes role in keeping testosterone active and available. It does this by blocking a protein called SHBG, which binds to testosterone and takes it out of commission. When magnesium is low, more testosterone gets tied up, and less is free to do its job. On top of that, magnesium supports better sleep, lowers inflammation, and helps convert cholesterol into testosterone in the first place.

The problem? Most Americans don’t get enough. And that has consequences. Studies have shown that magnesium supplementation boosts testosterone levels, especially in men who combine it with regular exercise.

Plastic & Radiation?

Time to talk about two suspects you’ve definitely heard of: plastic and cell phones. Are they conspiracy theory fluff, or real risks?

Let’s start with radiation from phones. A 2014 study showed a potential link between prolonged phone exposure near the groin and lower sperm count and mobility. Is it definitive? No. But if you’re planning on becoming a dad someday, maybe… let the phone live in your jacket instead.As for plastic, well, if you’ve read our in-depth edition on it, you’d know that it is everywhere. But did you know that they are also found in almost every part of our bodies? Including the male reproductive organs. A study published in the Toxicological Sciences Journal indicated that plastic was found in 100% of all 23 of the research participants tested. Although it is a small group of people, we don't think that anyone can doubt that it is definitely prevalent and should be studied. 

Though the long-term impact is still being studied, plastic exposure, according to the Virginia Commonwealth University, has been associated with oxidative stress and inflammation, two of testosterone’s least favorite words.

Final Thoughts

The more you support your body, the more it supports you. That means getting enough magnesium to free up more active testosterone, making time for regular exercise (especially strength-based), and not brushing off a vitamin D deficiency, sun exposure and diet both count. Try cutting back on processed foods and plastics where you can (think plastic water bottles, tupperware), and maybe rethink keeping your phone in your front pocket all day.

We get it. No guy wants to talk hormones over lunch. But ignoring them won’t make the fatigue, the belly fat, the brain fog, or the hit to your fertility, go away. If your testosterone could text you, it probably would’ve sent a few "we need to talk" messages by now. So consider this your reminder, less ghosting, more testing.

Until next week!

- Nicolas & Adrian (Chief Dietitian) | The 8% Authors