5 days Ago
Several large-scale studies have suggested that moderate alcohol consumption, especially of red wine, may confer some health benefits. However, it must be emphasised that overindulgent alcohol intake is always harmful to brain health. Excessive consumption of ethanol, which is the alcohol found in beverages, interferes with neuronal function and potentially hinders neurogenesis.
Alcohol Contrary to popular belief, research has found that alcohol does not induce cellular death within the brain. Nevertheless, the effects of excess alcohol on the brain are far from benign. Excessive ethanol levels cause brain atrophy, a phenomenon characterised by a diminution of the size of neurons.
This is a dose-dependent relationship, with increased alcohol intake correlated with more cerebral shrinkage. Moreover, alcohol’s effects extend to the intricate network of dendrites, the extensions of nerve cells responsible for signal transmission. While not causing cellular death, excessive alcohol can compromise these delicate inter-connected structures, thereby disrupting neuronal communication.
This profound alteration in neural connectivity may cause the characteristic unsteady staggering observed in chronic drunks. Therefore, enjoying alcohol in moderation, or abstaining altogether, are the best ways to protect your brain from the damaging effects of excess alcohol. However, my favourite drink is red wine, and it turns out this is an interesting subject in itself.
For a start, red wine in moderation may be beneficial to the brain, and this may be because it contains useful polyphenols, including an interesting compound called “resveratrol.” Studies on rodents have shown that red wine protected the hippocampus against ethanol-induced neuronal ill-effects, unlike for example, port wine or ethanol alone. Interestingly, red wine also did not impair neurogenesis in rodents.
In a 2022 study, researchers at Johns Hopkins established that resveratrol protects rodent brains from stroke damage. In their study, mice given resveratrol two hours before an induced ischemic stroke suffered significantly less brain damage compared to mice that did not receive the compound. This may be due to resveratrol’s ability to increase levels of an enzyme called heme oxygenase, which is known to shield nerve cells in the brain from damage.
It is unclear whether red wine confers the same brain protection for humans. In any case, the dosages of resveratrol needed to have any effect on humans is presently unknown. Overindulgent alcohol intake is always harmful to brain health.
— WILD LITTLE THINGS PHOTO/Pexels Curiously, another earlier Yale study claimed that enjoying red wine engages more of our brains than many other human behaviours. The simple act of sipping red wine involves a complex interplay of volatile wine molecules, air, and liquid controlled by sophisticated coordination of the tongue, jaw, cheek, and throat muscles. Inside the mouth, molecules in wine stimulate taste and olfactory receptors, sending complex sensory signals to the brain that triggers massive cognitive computation involving pattern recognition, memory, value judgment, emotion, and pleasure.
It is akin to listening to nice music or enjoying a good painting or satisfactorily solving a complicated maths problem. Such mental stimulation of the brain via red wine may have positive neuroprotective effects (see Mental Stimulation below). Against the above, one should note the findings of the Global Burden of Diseases report.
This is a worldwide review of illnesses, health factors, lifespan metrics, disease outcomes, etc, published annually since 1998. Since 2018, this comprehensive study of many millions of people had consistently found no safe level of alcohol consumption, including red wine. While the study did not specifically focus on brain effects, it highlighted the overall negative impacts of alcohol.
These include increased risks of various diseases and certain cancers, even at low levels. Smoking Tobacco smoke exposure significantly reduces neurogenesis in the hippocampus. The effect is dose-dependent, with more exposure to tobacco smoke leading to more pronounced reductions in new neuron formation.
The main reasons are: • smoking promotes “gliogenesis”, or the production of glial cells involved in protecting existing neurons in the brain, instead of neurogenesis, • tobacco smoke activates inflammatory responses in the brain, • unlike alcohol, smoking induces cell deaths in parts of the hippocampus; and, • synaptic plasticity (neuronal function) is significantly compromised due to poorer dendritic function affected by the toxins in tobacco smoke. Pollution It would be no shock to learn that environmental pollution affects neurogenesis adversely. The impact of pollutants is hard to determine, especially when the impacts of multiple combinations of pollutants are compounded.
Pollutants investigated included air particulates, other airborne pollutants, and micro- and nano-plastics (MNP) in water and food supplies. Impacts from agricultural antimicrobials misuse and chemical pollution were not investigated as the effects of persistently ingesting such contaminated items would almost certainly extend beyond brain issues. Micro and nano-plastics affect neurogenesis adversely.
— MALI MAEDER/Pexels There are several common brain impacts of air and plastic pollutants, which include: • disruptive (sometimes severe) inflammation, • neuronal damage and cell deaths in various parts of the brain, • changes to neurotransmitter levels which can often affect mental moods and responsiveness, and • DNA damage to brain cells. Additionally, MNPs are also known to detrimentally affect the internal mitochondrial of body and brain cells, impairing energy production in affected cells, and reducing the capacity for functions such as neurogenesis.Beyond diets While diets and the environment play significant roles, it is important to remember that neurogenesis is a complex process.
It can be influenced and improved by various diverse factors. Some positive factors are listed below. Exercise Regular physical activity is a potent stimulator of neurogenesis, boosting BDNF levels and promoting brain plasticity.
The effects of physical exertions include: • increasing blood flow to the brain, enhancing the delivery of oxygen and nutrients, which supports neurogenesis • promoting other growth factors besides BDNF, such as vascular endothelial growth factor (VEGF) and insulin-like growth factor 1 (IGF-1), both of which contribute to neurogenesis • increasing mitochondrial activity and energy production in cells within the dentate gyrus structure of the hippocampus. This production of energy supports the developmental needs of newly formed neurons in the subgranular zone. Sleep Quality sleep is essential for brain health, and critical for complex but essential processes such as “active systems consolidation” and the “glymphatic system”.
Active systems consolidation involves the consolidation of memories via the repeated reactivation of neural patterns associated with recently acquired (short-term) memories held in the hippocampus. This repetition facilitates the transfer of memory information from the hippocampus to other parts of the brain, primarily the neocortical networks (neocortex), for long-term storage. Sleep quality is essential for brain health.
— KETUT SUBIYANTO/Pexels The glymphatic system involves a physical “deep clean” of the brain to remove any metabolic wastes and toxins accumulated during waking hours. How this mechanism works is currently somewhat unclear due to conflicting research studies, but nevertheless it is universally agreed that it is critical for brain health. Sleep promotes neurogenesis via functions such as: • promoting the proliferation of neural progenitor cells in the subgranular zone and dentate gyrus of the hippocampus • helping the survival and maturation of newly generated neurons (presumably via actions of the glymphatic system) • regulating stress molecules, particularly a class of hormones called “glucocorticoids.
” Elevated levels of glucocorticoids are known to negatively impact neurogenesis substantially. Stress control The management of stress is often an understated factor in neurogenesis. One reason is that the hippocampus itself is significantly hampered by stress.
Therefore, controlling and lowering stress can improve neurogenesis in several important ways. • Lower stress levels improve BDNF signalling with TrkB (Tyrosine Kinase Receptor B) receptors in the hippocampus, a process essential for neurogenesis. This signalling pathway promotes neuronal survival and growth by improving dendritic and axonal health, and development of new neurons • Stress control can decrease the production of pro-inflammatory molecules such as cytokines, which can negatively impact hippocampal neurogenesis.
Effective stress management can enhance stress resilience, which is associated with improved neurogenesis. This creates a positive feedback loop, as increased neurogenesis itself contributes to stress resilience. This can maintain proper hippocampal function, including better regulation of the stress response and further improved neurogenesis.
There are many forms of stress management techniques which are surprisingly easy and helpful for neurogenesis. Immediate suggestions are meditation, yoga, playing with family/pets, pleasant walks, etc. In short, any activities which can calm the mind and/or lower blood pressure would likely be of some benefit.
Mental stimulation Engaging in mentally stimulating activities like puzzles, solving problems, and learning new skills can enhance neuroplasticity and support neurogenesis at all ages. Typically, such activities require a degree of mental exertion, preferably a tough but pleasant challenge, and not simple stuff like playing tic-tac-toe with a 3-year-old child. The level of mental effort expended is important.
This is because significant mental exertions are recognised by the entorhinal cortex (EC). The EC is connected to the hippocampus and is the primary gateway between the hippocampus and the neocortex. Acute stimulation of the EC promotes the proliferation of nascent neural cells in parts of the hippocampus, particularly the dentate gyrus and subventricular zone.
Keen mental stimulation also increases the levels of growth factors such as BDNF, IGF-1 (Insulin-like Growth Factor 1), and FGF-2 (Fibroblast Growth Factor 2), which advance the maturation of new neurons over time. Research has indicated that cognitive and spatial memory functions improved upon the maturation of such new neurons. Summary Whatever the age, human brains can potentially continue to develop and improve via a holistic approach that encompasses healthy diets, avoidance of pollutants, regular exercise, quality sleep, stress management, and mental stimulation.
The scientific evidence indicates that adult human brains are remarkably adaptable, and even small changes in lifestyle choices can have a profound impact on cognitive health, well-being, and brain regeneration, regardless of physical age. The views expressed here are entirely the writer’s own..
