Alzheimer’s Disease, An Evolutionary Neuroscience Perspective
Alzheimer’s Disease, An Evolutionary Neuroscience Perspective
Alzheimer’s Disease – Gerald J. Joseph Health Coach
INTRODUCTION Part 1
Alzheimer’s disease is now the third leading cause of death in the United States, following only cardio- vascular disease and cancer . There are approximately 5.2 million Americans with AD, but this estimate ignores the many young Americans destined to develop AD during their lifetimes: given the lifetime risk of approximately 15% when including all ApoE genotypes, as many as 45 million of the 318 million Americans now living may develop AD during their lifetimes if no prevention is instituted .
There is increasing urgency to develop effective prevention and treatment for Alzheimer’s disease (AD) as the aging population swells. Yet, our understanding remains limited for the elemental pathophysiological mechanisms of AD dementia that may be causal, compensatory, or epiphenomenal.
To this end, I hypothesis why AD exists from an evolutionary perspective which includes natural selection, co-evolution, adaptation, genetic drift, and other evolutionary forces. (Part 2)
As baby boomers enter the vulnerable ages for Alzheimer’s disease (AD), biomedical research is in a race against time to prevent, stabilize, or cure the disease. Implicitly or explicitly, rational therapeutic discovery relies on understanding the root cause (s) as well as intermediate and proximate pathophysiological processes of disease.
Basic research on AD has historically focused on characterizing the signature pathological lesions, that is, amyloid-β (Aβ) neuritic plaques and paired helical filament tau (PHFtau) neurofibrillary tangles, and the precedent and consequent molecular, biochemical, and physical mechanisms that most likely link these disease lesions to the neurodegeneration and cognitive decline caused by AD. 
Viewing AD from an evolutionary perspective prompts a rethinking of the way we describe the relationship between the clinical dementia and the neuropathology by which we define the disease. By integrating the fields of phylogeny, life history theory, genetics, biochemistry, nutrition, exercise science and evolutionary medicine, a unified theory of AD can be developed.
My hypotheses on the root cause (s) of AD centers on the consumption of the Western American diet and lack of persistence exercise. Over the past decade, neuroscientists have identified that physical activity stimulates both neurogenesis (the birth of new neurons) and optimizes functional connectivity within the human brain via neuroplasticity.
High consumption of plant-based foods and regular aerobic exercise produce many neuroprotective benefits—and when both are combined, they are the most effective way to bulk up gray matter brain volume and improve the integrity of your brain’s white matter communication lines.
From an evolutionary neuroscience perspective, physical activity stresses brain function because of the cognitively demanding foraging environment which forced our ancestors to engaged in daily aerobic physical activity to hunt-down and forage for food.
(The hunter–gatherers‘ daily energy expenditures for physical activity typically were at least 800 to 1200 kcal, 41 or about 3 to 5 times more than the average American adult today)
Simply put, our ancient genome has not had enough time to adapt to a non-daily aerobic activity lifestyle. Moreover, recently introduced foods such as grains, refined sugar, trans-fats, corn-fed altered animal, fowl & dairy proteins, alcohol and synthetic chemicals in processed food production further compromise our pre-designed constitution. The human body was designed very specifically.
By returning to this original design plan – and implementing a simpler ancestral hunter-gatherer diet – high in omega-3 fatty acids from marine and plant proteins and increased mineral rich phytonutrient rich foods. Phytonutrient rich foods include, root vegetables, vegetables, herbs, bulbs, and whole fruits. Like our ancestors did – we need to consume more raw nuts and seeds to thrive. Also much like our foraging ancestors – grains and dairy were not part of the daily diet. But aerobic activity like walking – and related large muscle exercise are paramount in the prevention reversal of almost all chronic disease syndromes including AD.
In conclusion, [s]cientists have discovered that exercise appears to build a brain that resists physical shrinkage and enhances cognitive flexibility. Exercise, the latest neuroscience suggests, does more to bolster thinking than thinking does. Daily exercise when combined with a high plant-based fatty acid diet challenge the brain to respond by increasing its neuroplasticity, by more myelin, and healthy synaptic connections. All of these essentials promote and improve better neural signaling which enhances cognitive function.
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