In this show, on the heels of the 21 insights around the clock, you’ll learn just how destructive excess artificial light is to your health and your overnight restoration, and you’ll also gain a better understanding of the complex interplay between your hormones and the habits that are at the core of your lifestyle.Before we begin, if you happened to miss part 1 or just want to refresh what we covered last week, click here to listen to that episode first. Now, onto part 2! Here are some key points we’ll go over during this episode:Most postmenopausal women find exercise training extremely frustrating as hormone response is altered as they age. In contrast, men usually don’t lose their GH levels until they’ve reached 50-55 years of age, and are also protected by their testosterone levels, which persist throughout life (if they’re not suffering from inflammation that is, because that will directly lower their testosterone levels). GH and testosterone are the key players that work to keep a man’s heart and muscles in shape.What happens when step 20 (the surge of prolactin) is broken in modern humans?This used to be more frequent among diabetics, but, because of our excessive technology use post-sunset, it’s becoming more common in all humans. Artificial lights tend to be super bright and completely interfere with the usual circadian signals from the hormone response, so it’s no wonder that light after sunset reduces the prolactin surge humans are supposed to experience. This is linked to sleep, as chronic lowered prolactin surges are associated with lower growth hormone secretion during the anabolic phases of sleep.One thing that really affects your cardiac and skeletal muscle function is lowered chronic GH secretion, because it directly affects the process of autophagy. This is why heart failure is strongly associated with low IGF-1 and sex steroid hormone levels. When growth hormone is not released in normal amounts, it also decreases our lean muscle mass and increases our fat percentage in all our organs and in our body. This leads to slowly declining organ dysfunction and poor body composition. We can measure this process clinically by looking for falling DHEA and GH/dopamine levels as we age.What happens in normal aging in step 21?Aging is among the most common features found in studies on modern humans when DHEA and GH craters on hormone panels. The loss of the prolactin surge is especially prominent in postmenopausal women. Most women begin to suffer from falling DHEA and GH levels around age 35-40 while they are still in peri-menopause. The higher their HS-CRP levels, the faster they enter peri-menopause and the quicker they enter menopause. They also age faster on a cellular level because their circadian chemical clocks are sped up. As a consequence, their telomeres shorten faster as well. Women have higher levels of leptin for childbearing, so they are more prone to leptin resistant issues than men. This helps explain why older women struggle with cognitive haze, loss of body composition, poor sleep, and increased levels of heart disease after menopause. Many physicians think the losses they suffer are due to the loss of estrogen from ovarian failure, but the loss of growth hormone and progesterone production are far more significant in their physiology. Progesterone is the off switch to anything that is pro-growth. Modern women are usually estrogen dominant even after menopause because of mismatches in circadian biology. Cognitive loss is especially common in post-menopausal women. They also lose on average 1% of their bone mineral density per year from menopause in large part due to the loss of progesterone, not estrogen.Loss of progesterone also corresponds to poor sleep in these women too. Replacing progesterone in women has a major effect on their sleep and bone stock. It also dramatically improves their memories and cognitive function as well.The cost of snacking after dinner and how it affects the circadian cycle