Hi, I'm nutrition & fitness expert JJ Virgin of JJVirgin.com, and today at About.com I'm going to talk to you about cortisol.Cortisol is an adrenal hormone that comes up in the morning to wake you up, and then has a natural rhythm throughout the day where it starts to come down towards the mid afternoon. That's probably when you go grab that espresso hit. And that's all preparing you for sleep as it drops down even more in the evening. The challenge is that coffee, alcohol, poor diet, lack of sleep, stress, more stress, those things all impact your cortisol rhythm and when your cortisol rhythm is off, you're off. For most people what happens is your cortisol starts to go high initially because of stress and when cortisol goes up, immune system goes down, testosterone goes down and when testosterone goes down, not only does it hit your libido and basically zap it, it also makes it hard for you to build muscle.It also impacts your fasting blood sugar – it makes your fasting blood sugar go up which can make you insulin resistant, and better at storing fat. It lowers serotonin and dopamine; the result of that is that you're hungrier and you're hungrier especially for carbohydrates. It also impacts your gut, your GI tract, and it makes your gut a little bit leakier, which means that you start to react to foods that you normally felt fine eating and that can cause an inflammatory response.As you can see, all of these things are not good. And over time, if you keep pushing on your adrenals and releasing too much cortisol, your body can't keep up with that demand and cortisol starts to get too low. And that's when you start to feel really tired. At first, your adrenaline comes up in response and you feel tired and wired and then eventually, you just flat out feel tired. So, what can you do about it? Well one of the most important things you can do for your adrenal glands is to get more Vitamin C. Your adrenal glands use Vitamin C primarily so this critical to do and I find most people need about 2-5 grams of Vitamin C in divided doses each day.The other important hormone that's produced by your adrenal glands is DHEA and quite often, when your body is pushing more over to cortisol, you start to lower your DHEA and, again, that's what starts to impact testosterone. So you might need to take a little extra DHEA.There are important lifestyle strategies that you can do that will make the biggest impact. The first one is get a good night's sleep. Now, quite often when you are stressed, its hard to do that. So you really want to put strategies in place so that you can get a good night's sleep, and I mean 7-9 hours of quality sleep each night. Next thing is to make sure that you're doing a little bit of burst-style training each day. That actually can help your sympathetic nervous system handle stress better. Another thing is to take some time out for a little bit of bliss every day. For you, that might be meditation, it might be a hot bath, it might be laughing with a friend, seeing a funny movie, petting your dog, reading a book, but something even for 15 minutes each day, think of that as rebuilding your adrenal glands. B Vitamins are also critical here. In fact, your body blows out your B Vitamins during stress, so that's another big deal. But as you can see, it takes an integrated approach to really heal your adrenal glands, restore your cortisol rhythm and get healthy.For more great tips, be sure to visit About.com.