You've been told to drink eight glasses of water a day. You've chased 10,000 steps like it's some kind of biological law. You've checked your cholesterol without being entirely sure what you're actually checking for. Most health content tells you what to do. Nobody explains why. That's the gap So That's Why was made to fill. Each week, Jen, Chris, and Matt take one everyday health question — the kind that's been nagging at the back of your mind, or that you've just accepted without thinking — and unpack the actual science behind it. Where did this idea come from? What's really happening inside your body? And does the evidence actually hold up? What they find is often surprising. The 10,000-steps rule was invented by a Japanese marketing team in 1964. The eight-glasses-of-water recommendation came from a misread document. The reason some people turn tomato-red when they exercise has nothing to do with fitness — it's about blood vessel density. The thing that makes you cry when you chop onions was only properly understood in 2002. Cholesterol is in every single cell of your body — so why the terrible reputation? The science is real, the research is specific, and the conversations are genuinely fascinating. And the three people having them have the backgrounds to get it right. Jen holds a PhD in biochemistry and molecular biology. She asks the questions you're thinking — informed ones, not naive ones — and keeps the conversation grounded in the human experience of all this biology. Chris is a formulation scientist with over 30 years of experience. He's read the studies, knows the mechanisms, and has the analogies that make complex biology actually click. Matt looks at the science and asks what it means for real people, with real lives, real schedules, and no time for perfectionism. Together they hit that sweet spot between too technical to understand and so simplified it's not actually true anymore. Getting there, it turns out, is harder than it sounds. So That's Why doesn't give you a list of rules to follow. It doesn't shame you for the things you haven't been doing. It explains the mechanism — the actual biology — so you can make decisions that fit your life, rather than just following advice that might not apply to you at all. Episodes run about 20 minutes. They're built for commutes, workouts, or cooking dinner. By the end of each one, you'll be able to explain the answer to someone else — which is the whole point. New episodes every week. Subscribe and find out why.