What does estrogen do in the brain? Estrogen is a hormone that protects the brain cells. Menopausal women have a 20 to 30% reduction in brain glucose metabolism. So, what happens? Well, we get brain fog, we start to forget people’s names, we forget why we walked into the room. This is all because of the loss of estrogen, something that I was never told 12 years ago when I was scanning these women’s brains and no one told me that estrogen may play a role. As I was moving down in my studies figuring out what is this disease, why does it exist in women, why why why, I came to the conclusion of could it be estrogen? Could it be? Well, let’s see. At around 40 45 years old, depending on your genetic profile, we see a drop of estrogen. But, how does estrogen relate to the brain? Well, we have Dr. Lisa Mosconi who’s proven to us time and time again that estrogen is a neuroprotective hormone. It doesn’t just relate to your ovaries. And menopause is a neurocognitive transition. What does estrogen do in the brain? Estrogen is a hormone that protects the brain cells. It helps you utilize glucose and glucose is the primary fuel source of the brain. So, when we run out of glucose, which is what she saw, you can have a look up here in the brain scans. She found that menopausal women have a 20 to 30% reduction in brain glucose metabolism. That means that during this midlife stage and beyond, your brain cannot utilize its primary fuel source effectively. So, what happens? Well, we get brain fog, we start to forget people’s names, we forget why we walked into the room, we have sleeping complaints, we have hot flashes. This is all because of the loss of estrogen, something that I was never told 12 years ago when I was scanning these women’s brains and no one told me that estrogen may play a role. Now, again, I’m not here to cherry-pick anything, but I will tell you that we do have enormous amounts of data to correspond with the loss of estrogen and the loss of testosterone and the loss of progesterone that may equate to why our brain is shrinking. The first part to go, ladies and gentlemen, during mild cognitive impairment is this little area in the brain. It sits right here in the temporal lobes called the hippocampus. The hippocampus is this seahorse-shaped structure and this is where our memories lie. It’s where memory formation takes place. It’s where learning takes place and this is the first thing to go during the aging process and during Alzheimer’s disease development. But, it turns out that it is also the only part of the brain that can grow new brain cells. I want you to think I mentioned earlier connections. We’re born with 87 billion neurons. At birth, we have 3,000 connections per neuron. At adulthood, when our brain fully develops at age 25 for men, that’s about 40. I mean, we have around 15,000 connections. Every time you see something new that you haven’t seen before, you’re forming a new connection. Every time you see somebody that you’ve never seen before, you’re forming a new connection. But, when estrogen goes down or when you are stressed or due to lack of physical activity or when you are sleep deprived, those connections start to die. And when we see brain scans on MRIs, we see smaller brains. It’s not because our brain cells are dying, it’s because the connections are dying. So, Alzheimer’s disease is a network insufficiency. Those connections start to die off and that’s what’s scary.