 Hey everybody, Dr. O. In this video we're going to talk about the major classes of hormones as far as what they're made of. So the first little pro tip I'll give you is that the huge majority of proteins are going to be made of peptides or proteins, so these kind of short polypeptide chains or short proteins, and then longer proteins. There's only a handful of hormones that are amine hormones, meaning they're just made from an individual amino acid, and there's only a handful that are steroid hormones made from fat. So here's how I remember them. Rather than memorizing the entire list, just remember the ones that are amine hormones, remember the ones that are steroid hormones, and if they're not one of those two, then they fall into this larger group of the protein-based peptide hormones. That's how I remember them. Alright, let's start with the amine hormones. So here's some examples. When you take an individual amino acid and modify it to make a hormone, these are going to be your amine hormones. The two amino acids that are used this way are going to be tyrosine and tryptophan. Let's start with tryptophan because there's only one example. Tryptophan becomes melatonin. So melatonin is needed for sleep-wake cycles. People take melatonin to help them sleep, these kind of things. Melatonin is way more powerful than that, but we'll cover that later. This is where the idea, so like turkey has a lot of tryptophan, so this is where the idea that eating a bunch of turkey would make you tired. Most of the research doesn't actually support that. I think it's just the size of the meal that like think about Thanksgiving or something. I can fall into a ham coma as well as like a turkey coma, I think. But tyrosine is more important, and this is why it's important to understand what we need to build hormones. So tyrosine, there's epinephrine, I'll show you that in a moment, but the first thing I think of is thyroid hormones. So the amino acid tyrosine and then the mineral iodine are needed to make thyroid hormones. So if you're iodine deficient, even if you have enough tyrosine, even if you're thyroid gland works, you can't make thyroid hormone. So in the developing world, the most common cause of hypothyroidism and or goiter is a lack of iodine. But here in the U.S., if you are consuming enough iodine, it's using more inflammatory conditions. But that's why it's important to understand what we need to make these hormones. So tyrosine is needed to make your thyroid hormones, which we'll cover in a separate video. They're also needed to make what are called the catecholamines. You see one here, epinephrine or adrenaline, but we also have nor epinephrine or noradrenaline, and then you have dopamine. So these would be key examples. So tyrosine makes several of these important hormones. All right. So those are your amine hormones. Now you look at your peptide and protein hormones. We won't go through the whole list, but just remember if they're not an amine hormone or a steroid hormone, they have to fall in here somewhere. So peptide hormones are going to be short chains of amino acids, and that's going to be like oxytocin and antidiuretic hormone. It'll be great examples. Peptide hormones, you've got growth hormone, and then you're going to add a tropins like follicle-stimulating hormone. Those would be examples of your protein hormones, but we won't spend too much time on those. We'll move into then we have the steroid hormones. So these are going to be made from cholesterol. And that's very important, right? Cholesterol is demonized. But cholesterol is needed to make all of our steroid hormones. That's why every cell in your body makes cholesterol, because you need it for your cell membranes. And then you do it, and it's going to be highly concentrated in places like your gonads and your adrenal glands because of the need for cholesterol to make these hormones here, these steroid hormones. All right. So some examples. Here you see testosterone and progesterone. Two of your sex hormones would be great examples. And then we have, I'll talk about this a little bit more. So your lipid-based hormones are going to have a very long half-life because oil and water don't mix. So these lipid-based hormones have to be transported through your body on proteins. So for example, we have sex hormone binding globulin is what binds your sex hormones and carries it through your blood. So because of this and the fact that they have a more complex structure, they do have a long half-life. They stay around in your body a much longer time than some of the other hormones. Let me give you an example. Cortisol, which so cortisol would be one of your stress hormone, your stress hormone made from the adrenal glands. I'll show you that in a moment. Has a half-life of 60 to 90 minutes. This is why when something stressful happens, it takes a while to come back down. But epinephrine or adrenaline has a half-life of a minute or so. So if you're still feeling kind of amped up after almost getting hit by a bus or something, cortisol is the one that's still impacting you. The adrenaline's already gone. All right. So I didn't mention one thing, just this idea. I talked about bound proteins or bound hormones, but this idea of free versus bound hormones is important in all different areas. Free hormones are only going to last in your body for less than an hour. So if a hormone isn't being bound up, it's going to be used up pretty quickly, meaning it has to be produced really quickly and constantly. Your hormones that are bound up, which would be your sex hormones or your lipid-based hormones, so your sex hormones and the adrenal hormones, and then thyroid hormone as well. Thyroid hormone is kind of interesting. It's an amino acid derivative, but it has to be bound. I'll explain that more later. They're going to last a lot longer time in your body. One last thing. I know this is getting kind of long, but this is a very important one to me. Again, understanding why the structure of these hormones is so important, there are several key examples. And here's one. You'll see that cholesterol is needed to make cortisol, your stress hormones. So this is called, this is known as the pregnenolone steel. So pregnenolone is actually the precursor hormone that makes cortisol and also makes your sex hormones. So this idea of pregnenolone steel is basically, if you're under a lot of stress and your body's churning out massive amounts of cortisol, you're going to run out of the building blocks you need to make other hormones like your sex hormones. So you've got testosterone, estrogen, DHEA. These would be key examples. This is why people that are under stress for long periods of time will see drops in their sex hormone levels, maybe a drop in libido, maybe they'll have trouble reproducing if they're trying to write these types of things. So again, understanding that every time you're stressed out, your body has to decide, should I make more sex hormones or make more cortisol? It makes more cortisol at the expense of your sex hormones. So this could be where some of the libido and sexual function side effects of stress come from. So I guess kind of interesting. All right. So those, that's how we describe and define hormones based on what they're made of. I hope this helped. Have a wonderful day. Be blessed.