If you have not read Parts 1 , 2 , and 3 , I encourage you to do so before continuing. What follows will mean more if you understand what came before it. Part 1 was about what plastic is doing inside your body. Part 2 was about what you can do about it. Part 3 was the hardest thing I have ever written — a reckoning with what plastic is doing to our species, our fertility, and the generations that will follow us into a world we have permanently altered. I ended Part 3 with two

Why I Wrote Part 3 My job is to help you live better. Longevity medicine is about understanding the forces that degrade human vitality and doing everything in our power to slow them down. I want to tell you what started this research. Over the past year I began noticing a pattern in my practice that I could not ignore: young healthy men in their early twenties coming in with low testosterone. By the time I saw the sixth one, I knew something was wrong that went beyond the usu

Right on schedule, a new COVID variant has arrived. And right on schedule, the headlines are coming. "New COVID Variant Detected in 25 States." "75 Mutations May Evade Immunity." ... The Facts BA.3.2 is a new Omicron subvariant first identified in South Africa in November 2024. As of this month, it has been detected in 23 countries and found in wastewater samples from 25 U.S. states. Those two sentences are going to generate a month's worth of alarming chyrons. Wastewater sur

Last week I told you something that I cannot stop thinking about. I told you that the plastic water bottle you discarded today will still exist in 500 years. I told you that a single liter of bottled water contains 240,000 nanoplastic fragments, and that if you drink a liter a day, you are ingesting 87.6 million of them per year from that single source alone. I told you that the so-called blood-brain barrier — one of the body's most trusted defenses — cannot stop these partic