The brain and the spinal cord are the control centre of the body. They mediate the entirety of our physiology — regulating our breathing and heart rate, keeping our hormones in check, stimulating proper digestion, maintaining a balanced mood, memory and focus, among literally all other functions — they do it all.
When these two organs are nourished, the system will be healthier overall. As with any system, metabolic and environmental wastes, excess fluid, and other soluble materials build-up and need to be circulated and removed to ensure optimal functioning. The central nervous system (CNS), comprising the brain and the spinal cord, is no different. While the rest of the body relies on the lymphatic system to shuttle away toxins to organs of elimination through which they are excreted, the CNS is not accessible by the lymphatic system.
Instead, the CNS relies on what is now known as the glymphatic system to assist in removing unneeded and potentially harmful waste. This system is a relatively new discovery and plays an integral role in the health of the brain and spinal cord. The byproducts from the CNS circulate in the cerebrospinal fluid — the fluid that surrounds the brain and spinal cord, cushioning and nourishing them, but also serving as an area for waste disposal. These wastes need to be removed. Like anywhere in the body, waste build-up can cause dysfunction, leading to symptoms and disease over time. An analogy would be a stagnant pond versus a flowing river; the moving water is fresher, cleaner and more nourishing than the water that is sitting. Circulation is key for healthy, clear CSF and healthy, clear CSF is key for an optimally functioning brain.
While the glymphatic system a new area of study, the research already provides ways we can support this integral system. One key lifestyle factor that improves glymphatic function is sleep. Evidence suggests that there is a dramatic increase in the activity of this system during sleep in mice. When the mice are awake, on the other hand, this system is suppressed. It is therefore thought that while we sleep, there is an increased clearance of various metabolites and, in effect, the brain can clear itself of neurotoxic waste products that are produced during waking hours.
Another factor that likely plays a role in glymphatic function is stress. Epinephrine (a stress hormone also known as adrenaline) may be a suppressor of glymphatic function. This hormone is at higher levels while we are awake compared to when when we are sleeping, and may be responsible for suppressing the glymphatics. Aging is another cause of a decline in glymphatic system activity. However, it is important to remember that healthy diet and lifestyle habits impact how “well” we age. The fewer stressors on the system, the more we can delay the negative signs of aging. Stressors include processed foods, over- or under-exercising, lack of hydration and sleep, and your mindset, to name a few. The health of your circulatory and cardiovascular system also play a likely role in how well this system functions. And, as always in naturopathic medicine, everything is connected. It is my opinion that the more we focus on healthy lifestyle, dietary, emotional and spiritual habits, the healthier this system will remain as well.