By Ilene S. Ruhoy, MD, PhD
As we get older, even if we are healthy, all organs undergo change with each passing decade. And our brains are no exception. Age-related changes of the brain are not necessarily indicative of disease or degeneration. Brain cells no longer divide after we are born as do many other cells in our bodies. Brain cells can potentially live the same long life we do, unless they have reason not to. When we suffer from chronic exposures, stress, and unhealthy living, the brain cells can swell and become damaged, the mitochondria of the cells can become dysfunctional, and the strength and density of connections may be less than optimal. Furthermore, inflammation can influence epigenetic changes and genetic expression, ultimately changing the brain environment into an inhospitable milieu.
The weight of the brain when we are born is 350 grams, then increases to 1400 grams when we reach age 20, and then decreases to 1100 grams when we approach our 80s. This is the average for a healthy brain. Most of the loss of volume that occurs as we age is in the cortex of the brain. The cortex plays a role in many of the brain’s primary functions including cognition, emotion, language, memory, focus, attention, and social interaction.
The brain has approximately 100 billion neurons each of which can make connections with over 1000 other neurons. In fact, the adult brain has approximately 60 trillion neuronal connections. Neurons do not self-renew and plasticity of the brain that is often discussed involves modulating connections between existing neurons. Neurogenesis (the making of new brain cells – different from cell-renewal) may occur in specific areas of the brain, mainly the subventricular zone and the dentate gyrus of the hippocampus.
When we can manage and prevent wayward neuroinflammation, cell integrity may be preserved. If not, the activities of the neuronal cells can be compromised by alterations in not only neurotransmitter synthesis and degradation, but by changes in the function and levels of particular neurotropic hormones and growth factors. Furthermore, as we age, there are subtle and incremental, but cumulative, changes in the permeability of the blood-brain-barrier (so more toxins get through), the blood flow to the brain (so decreased oxygen and nutrient delivery), cerebral metabolism (so an increase in metabolic waste by-products), and decreased mitochondrial function (so an increased in damaged reactive oxygen species (i.e., free radicals).
Initially, when we are in young adulthood, compensation of loss of neuronal integrity can be made more easily by improved connections, or synaptic transmission. But that resilience wanes as we age. But it does not mean your brain loses its innate ability to maintain neurogenesis. With healthy living and an anti-inflammatory lifestyle, we can maintain robust neuron density.
In modern times, we see more and more symptoms and disease associated with the brain in younger people. In fact, in the past decade there has been an increase in stroke incidence in both male and female young adults. There has also been in an increase in the last 10 years of early onset cognitive decline.
Because of this troubling trend, we can no longer think about our brain in terms of our age as it is never too early in life to embrace brain health. In fact, the earlier we start living for our future the better our present will be.
Here are ten suggestions to start caring for your brain:
1. Sleep and wake hygiene. The brain is a circadian organ and thrives on routine and rhythm and a critical part of that rhythm is the sleep-wake cycle. In addition, the glymphatic system of our brain is most active during sleep and helps rid the brain of cellular debris and metabolic waste by-products.
2. Nutrition. The science is clear. Plant-based foods contain all the compounds necessary for healthy cellular function.
3. Whole grains. The brain prefers the glucose molecule for energy. This glucose is not meant to come in the form of doughnuts and cookies but rather whole grains. Our bodies have intricate biochemical mechanisms to break down whole grains to deliver to the brain the glucose it so craves in the appropriate amounts at the appropriate pace. Don’t starve your brain.
4. Movement and sweat each day. A daily form of exercise – yoga, running, walking, cycling – can help improve blood flow to the brain and maintain the tight junctions of the blood-brain-barrier.
5. Stress management. Find a way. Journal, talk to a friend, breathing exercises, seek psychotherapy, for a walk, etc. The stress response, especially when chronic, can create neuroinflammation from the surge of stress hormones.
6. Fix your gut. We know more today about the gut-brain connection than ever before and there is no longer any doubt that the health of our gut plays a role. But it is not as easy as taking probiotics. But it is also not hard with the right guidance. When I fix my patient’s guts, it changes so much about their lives.
7. Avoid long term use of medications. Some medications are necessary, some are not, some do more harm than good. Multiple medications, referred to as polypharmacy, definitely does more harm than good.
8. Minimize exposures. Eat organic foods, use green cleaning and personal care products, get out in nature and take deep breaths, and filter your water. Our world gets dirtier with each passing decade so do what you can to protect your brain.
9. Learn something new every month. That’s not so hard. Even if it’s reading a book. But consider learning a language, taking up a new sport, or learning how to play an instrument.
10. Be kind to yourself and to others.
We have but one wonderful and beautiful brain that helps us to be who we are at our core. Protect it, nourish it, and care for it.