Sleep is a fundamental part of our lives. It's a time for our bodies and minds to rest, rejuvenate, and prepare for the next day. But not all sleep is created equal. There's light sleep, deep sleep, and REM sleep. Each stage has its unique benefits and functions. But one type of sleep stands out as particularly crucial: core sleep. Core sleep encompasses deep sleep and REM sleep. It's during these stages that our bodies undergo essential physical restoration and our minds process and consolidate memories. But how much core sleep do we actually need? This question is more complex than it might seem. The answer can depend on a variety of factors, including age, lifestyle, and overall health. In this article, we'll delve into the science of core sleep. We'll explore its importance, how much is ideal, and how to optimize it for better health and cognitive function. Whether you're a health coach, a science journalist, or a biohacker, this comprehensive guide will provide you with the insights you need to understand and improve your core sleep.