Hi everyone. Welcome back to today's module where we are talking about the endocrine system, and we're going to later introduce some yoga that hopefully will tie in to what you're learning in lecture, and start to make an impact on creating really positive harmonious feedback loops in our endocrine system. So when we talk about the endocrine system, what I want everybody to come away with is an understanding of the endocrine system as a whole. So sometimes we think of hormones and endocrine system as things that control things like sexual differentiation, or secondary sexual characteristics, or the menstrual cycle. We're mostly usually focusing on things like estrogen and testosterone, but I want to widen that understandings that we all leave with an impact and an understanding of how hormones regulate so many other things. They regulate things like our sleep patterns, they regulate things like fear, anger, thirst, hunger, our ability to break down foods, so some of that control of the digestive system that we went through, blood sugar levels, blood pressure. These are all things that can be regulated by this huge category of molecules called hormones. What I want us to do is really start to look at that and the implications that these hormones have on all sorts of systems, all sorts of functioning, and how things we do on a daily basis whether it be yoga, or mindfulness, or meditation, or breathing exercises, can really have an impact on creating a stable hormone system. So what is the endocrine system? It's this complicated system that really has two main components. It has the hormones themselves which are chemical messengers, and they can be lots of different types, and it has the gland that those chemicals are going to act on. So what this means is that the hormone system is unique because it sends out chemical messengers into the bloodstream. So usually, what happens is we have cells communicating with cells right next to it. Where we have neurons, like we talked about where the neurons are right next to each other. But in the case of the hormone system, we have certain glands that are going to send out hormones in our bloodstream, and they're going to act on very far distances. So the image that you're seeing is going to include the hypothalamus and the pituitary gland which controls a huge amount of this activation of different glands, or varied endocrine glands throughout your body. Because this is a system where we have chemical messengers being sent through the blood and then acting on distant organs or distinct glands, it means that it's slow acting. This can be really great because some of our functions need to be stable, they need to be reactive over long periods of time, but it also means it requires a long period of time or daily practice to actually start to change them. So I mentioned before but we have all of these different hormones and we have all of these different systems working within the endocrine system to do a lot of different things. So some of those things are our mood, we've all been in a bad mood, that maybe you can't just shake your way out of. Growth and development. So much of our development process like literally from when we're babies to adults it's going to be modulated by endocrines tissue function. So things like the liver secretes enzymes, ability to digest food, our metabolism, how much we're digesting, how quickly, how quickly we burn through fat, how quickly we burn through our food, certain sexual functions, reproductive processes, and then homeostasis. This term we keep referring to way back in the first module, which is how we're able to keep all of these steady states that we need, like temperature, like pH, all of these, the blood pressure, our water levels. All of these things we don't even usually think about are going to be controlled by all of these chemical messengers throughout our body. The overall endocrine system is going to require the same steps regardless of the hormone, regardless of the gland, and that is, something has to make this chemical messenger. For example, we could talk about estrogen. We have to have estrogen made, men and women. We have to store it. We have to transport it. It has to be picked up by some distant gland. It has to do whatever it's going to do, and then it has to be broken down. My point in telling you this is that it is slow. So if you feel like you're stressed out all the time and you're starting to have physical ramifications of being stressed out, it's not a quick switch. I tell you this, so you have a little bit of patience with yourself. As we move into some of the yoga, and as we move into some of the mindfulness that you're not just saying like why don't I feel better? Why don't I feel less stressed.? These things actually take a lot of time. So when I say that the endocrine system is slow acting, it also means that it needs constant repeating input to make any change. The reason for this is that our endocrine system works on what are called feedback loops. The feedback loop is going to be some sort of chemical that's secreted by a gland, that's going to act on a different gland. At some point, it's going to want a change or it's going to get feedback from the overall system of what to do next. So sometimes when we talk about stress which we'll get to next, we can have this constant feedback loop of stress. You think of a stressful example, your body has a stressful reaction, you have chemical messengers and hormones that are part of that, and to really make an impact on stopping that feedback loop, we have to put constant daily effort into it. So things like breathing, things like meditation, things like mindful practices like yoga, we actually have to constantly repeat them. So it's not just doing it once and hoping to have this huge systemic impact because these chemicals are in our blood. They're acting over distances. They're at different concentrations. So we start to have an impact on our bodies on a daily basis, so that we start to really accumulate some change at a hormonal endocrine level.
