Did you know that neurons can live more than 100 years? That’s good news—if you have been taking care of them. Hopefully you are, because currently you have pretty much the same neurons you had when you were a baby. Your brain contains at least 86 billion neurons, all ow which are very sensitive to lack of oxygen. They can become weakened and die after just a few minutes without adequate levels of oxygen. Twenty percent of your entire blood supply is earmarked to supplying your brain with oxygen, glucose, and micronutrients. Scientists believe that high blood-sugar spikes to the brain can be damaging to your neurons, one reason for avoiding sugary foods and beverages and simple refined carbs. Brain neurons are protected by the 22-bone skull and three membrane layers known as the dura mater, arachnoid mater, and the pia mater. Immune vessels run throughout these three membranes, directly connecting the immune system and brain tissue. More tomorrow.