Andrew Huberman· PhD
the normative values are like frankly embarrassingly all over the place um they're mostly going to be like 5 to 25 as a quote unquote normative value but that's outrageous we also know those numbers vary massively by age by sex um and throughout the day and so if you only are taking a single point let's assume you're doing a fasted blood draw which is what most folks do it's really only going to tell you a lot about what's happening in that moment we need to know well like maybe let's say my cortisol was if I'm a say 38-year-old woman and my 7 A.M cortisol was you know 15 milligram per decer that's pretty good but if it's 15 milligrams per deciliter at 3 p.m. oh boy I'm I'm probably having some issues right so there's a change throughout the day and you need to be able to plot that curve so you can actually well pretty standard practice that we do is we look at cortisol throughout the day we're going to take multiple markers because I don't want to just see your Baseline cortisol I want to see this curve throughout the day that's going to tell me a ton about U again is your sleep being caused by this regulation um is it your training is it something else so I would like take a single Baseline blood marker of cortisol with a lot of grain of salt we we typically measure it at least three times throughout the day so something like 6:00 to 9:00 a.m. 12: to 3 and then something like closer to the evening oftentimes we do much more we'll do like seven points or something like that throughout the day depending on the situation so you want to be careful of that