Life Extension Magazine®
You probably won’t hear this from your doctor, but your brain’s gradually shrinking as you read this. Why? A certain amount of physical wasting or atrophy—also medically termed “regional deterioration of brain structure”—occurs in the brain naturally with age.1 The impact of these structural alterations is vastly underestimated by both physicians and patients alike. This process usually commences around age 30, with marked acceleration observed at 50. The results of physical brain deterioration can be dramatic. They include neurocognitive deficits, such as diminished attention span, verbal skills, spatial perception, deficits in abstract thinking and creativity, along with increased difficulty learning new tasks and retaining new information, flagging memory, and deteriorating sleep quality. Maintaining a youthful brain in the face of these detriments of aging is perhaps the most crucial challenge of aging. The brain, our most important organ, is responsible for orchestrating a complex symphony of hormonal, neurochemical, and electrical signals to maintain the body in a state of vibrant health. In this article, you will learn of the many insults on brain health in the modern world and what you can do to halt and reverse them. Attention ImpairmentSubtle declines in memory, reasoning, and cognition are statistically likely to progress well beyond mere “forgetfulness” among many individuals. Sadly, a significant number of Americans will succumb to cognitive decline, and eventually to dementia, well before their bodies have given out. According to the Alzheimer’s Association, 5.3 million Americans are currently afflicted with this mind-robbing disease, and the ranks of the affected are expected to swell in coming years as more Baby Boomers attain elder status.2 Mild cognitive impairment (MCI) is a related condition that often precedes the development of Alzheimer’s-type dementia. Some international studies suggest that up to 40% of older people will be affected by mild cognitive impairment worldwide, and many of these patients will go on to develop Alzheimer’s-type dementia.3,4 In a lecture I delivered at Columbia University, I noted that dementia takes 15 to 20 years to develop; by 80-85 years of age, up to 50% of Americans will suffer some form of dementia. But even by 70 or 80, nearly everyone experiences some cognitive loss. Obesity and Cognitive DeclineIn addition to brain atrophy, researchers have reported that just being overweight in middle age puts you at greater risk of having decreased cognitive abilities and suffering “steeper cognitive decline” later in life.7 Using sophisticated brain imaging techniques, researchers have shown that obese people literally have smaller brains than their age-matched, normal-weight peers. Using MRI analysis techniques, for example, scientists at the University of Pittsburgh showed that, among elderly subjects with apparently normal cognition, obesity is associated with declining volumes in several key areas of the brain.8 Furthermore, research suggests that the decline of the key brain chemical dopamine is related to the impulse to overeat, which in turn encourages obesity, perpetuating a vicious cycle of weight gain and increasing imbalances in brain neurotransmitters.9,10 This means that obesity accelerates cognitive decline, damages attention, erodes memory, and decreases your brain’s processing speed, while altering brain voltage.
CalcificationAging is often accompanied by increased calcification; we essentially “turn to stone.” Brain calcification, which is sometimes associated with hyperparathyroidism, results in impaired brain processing speed.11-13 In older women with osteoporosis, bone loss has been shown to predict cognitive decline.14,15 That’s why I often say “frail frame; frail brain.” Osteoporosis and osteopenia destroy your brain, not just your bones. Interestingly, menopause induced by surgical removal of the ovaries decreases brain processing speed.16 Evidently, hormonal factors may help explain why women have increased rates of cognitive decline and dementia compared to men, which illustrates the importance of restoring the whole body to youthful health through the use of bioidentical hormones. AddictionDrug abuse and addiction impact numerous aspects of a person’s life. While the immediate costs are fairly well known, the long-term consequences of addiction receive less attention. Accelerated cognitive decline is one of them. Disturbances in the dopamine-driven “reward cascade” in the brain are associated with multiple drug-seeking behaviors. Alcohol, cocaine, heroin, marijuana, nicotine, and glucose all cause activation and neuronal release of brain dopamine. Dr. Kenneth Blum and I, along with other colleagues, have published numerous articles regarding our discovery that individuals with genetically determined deficits in certain dopamine receptors are at greater risk of addiction, due to abnormal cravings that are only satisfied by the “feel good” dopamine molecule. We have related this genetic abnormality to addictive, compulsive, and impulsive behaviors ranging from drug abuse to gambling to overeating that leads to morbid obesity.17-19 Experts are now projecting that as Baby Boomers age, the ranks of older drug abusers will grow significantly.20,21 Some drugs of abuse are outright neurotoxic, destroying brain structures even as they enhance the desire to continue abusing them.22 Others, like nicotine from tobacco, temporarily enhance memory and attention, but in the long term, tobacco “accelerates dementia processes.”23 Alcohol abuse results in cognitive impairment that may last long after sobriety is achieved. Alcohol abuse during pregnancy results in potentially severe, irreparable harm to the fetus’ developing nervous system. Tragically, fetal alcohol syndrome is the leading cause of retardation around the world.24 Alcohol-related impairments of executive brain functions manifest as a reduced ability to focus on tasks and pay attention.25 Other drugs that induce long-term cognitive deficits include cocaine, GBH (the so-called date-rape drug), amphetamines, MDMA (ecstasy), marijuana, and opiates such as heroin and oxycontin.22,26-31 Strong Muscles, Strong BrainFortunately, it is possible to fight back and greatly improve one’s odds of aging gracefully with a sharp mind fully intact. From nutrients that support healthy brain structure to bio-identical hormones that help maintain youthful brain function, there’s plenty that can be done to prevent cognitive decline. Surprisingly, it begins not with the mind itself, but with muscle. Studies have repeatedly shown that older individuals who exercise regularly and maintain a healthy weight are less likely to succumb to cognitive decline, mild cognitive impairment (MCI), and Alzheimer’s disease than their heavier, more sedentary peers.34-36 Shrinking muscle mass correlates with declining cerebral blood flow. Since sluggish cerebral blood flow is associated with a greater risk of cognitive impairment, it follows that building and maintaining adequate muscle mass equates with maintaining healthy cerebral blood flow. We once assumed that cerebral blood flow remains more or less constant, but we have recently discovered that exercise increases cerebral blood flow, possibly by speeding up brain metabolism.34,35,37,46,47
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Strategies for Preserving and Enhancing Brain FunctionScientists recently published the results of a controlled trial that examined the effects of aerobic exercise on cognition and other biomarkers of Alzheimer’s disease among older adults diagnosed with mild cognitive impairment. Subjects were randomly assigned to engage in intensive aerobic exercise for 45 to 60 minutes per day, four days a week, for six months. Control subjects underwent supervised stretching sessions for equivalent periods, but did not engage in vigorous exercise. Results showed that aerobic exercise, but not simple stretching, acted as a “potent [non-drug-induced] intervention that improves executive control processes for older women at high risk of cognitive decline.”38 Another recent study conducted by the Mayo Clinic on more than 1,300 subjects concluded, “Any frequency of moderate exercise performed in midlife or late life was associated with a reduced odds of having mild cognitive impairment.”37
The benefits of exercise are achieved through a variety of mechanisms, including enhanced production of key neurotransmitters.43,44 As I note in my book Younger You: Unlock the Hidden Power of Your Brain to Look and Feel 15 Years Younger (McGraw-Hill, 2006), serotonin is an important brain chemical messenger associated with the regulation of mood and sleep. Deficiencies yield depression, fatigue, and poor sleep. Acetylcholine is a key neurotransmitter involved in cognition, memory, and learning. A deficit in acetylcholine, and its receptors, is associated with dementia and Alzheimer’s disease. Dopamine affects the body’s ability to regulate weight, experience pleasure, and feel energetic. When dopamine levels fall, obesity, addiction, and fatigue may result. Gamma-aminobutyric acid (GABA) is a crucial neurotransmitter that has a stabilizing effect on the brain’s other chemical messengers. GABA controls the brain’s rhythm, affecting one’s ability to handle stress and to function mentally and physically at a calm, steady pace.49 In addition to these four foundational neurotransmitters, studies have shown that exercise increases production of a substance known as brain-derived neurotrophic factor, which has been associated, at least in women, with enhanced cognitive function and brain plasticity.44,50-52 Exercise also encourages angiogenesis, or the formation of new blood supply structures. This is important for growing new brain cells and their supporting structures.50,53,54
The Power of Neurogenesis: New Brain Growth and LifeWhen I attended medical school, we learned that many types of cells regenerate more or less constantly throughout life; in essence, entire organs are eventually renewed as old cells are replaced. But the brain and central nervous system represented a notable exception. Brain cells are finite, we were told, and soon after birth the ability to grow and regenerate neurons is irrevocably lost. Furthermore, dogma held, the myriad pathways and connections among adult brain cells are “fixed and immutable,” incapable of further adaptation, and certainly incapable of new growth. We now know this is incorrect.55-58 Research conducted since the 1970s has shown that the growth of new nerves (a process known as neurogenesis) does occur. This growth plays an important role in the brain’s plasticity, or ability to remodel, especially in key areas of the brain, such as the hippocampus, which is responsible for some of the most important higher cognitive functions, including memory and emotion. It’s no coincidence that Alzheimer’s disease strikes the hippocampus first, eroding long-term memory. While the hippocampus is vulnerable to the ravages of Alzheimer’s disease, it also responds to better nutrition and increased exercise, thereby promoting neurogenesis. In fact, scientists are only beginning to fully appreciate the dramatic implications of this discovery, which may yield new treatments for conditions ranging from mental illness and addiction to age-associated declines in memory and cognition.55,59-62 Exercise Improves SleepOne of the chief complaints among many of my elderly patients is poor sleep quality. Fortunately, exercise also improves sleep. And better sleep is also associated with increased neurogenesis in the adult brain.63 Conversely, poor sleep may restrict neurogenesis. By engaging in regular aerobic exercise you’ll sleep better, age more slowly and improve the architecture, and thus health, of your brain. Robust Brain Function, Robust LibidoA healthy brain correlates with better mental acuity—but also better sex. There’s a common saying that “the brain is the greatest erogenous zone.” This is truer than most of us realize. When the brain is alive, so are the sex organs. I’ve treated patients who came to me complaining of multiple problems, including failing memory and declining cognition, not to mention poor sleep quality and sluggish libido. My patients have experienced remarkable success reversing these declines using treatments ranging from nutrients, to better dietary habits, to electrocranial stimulation, to bioidentical hormone replacement therapy. In some cases it is necessary to treat underlying conditions such as hypertension, which is a contributing factor in vascular dementia, before success is achieved. After treatment, patients experience improved memory, reasoning and intellect, and they have been known to rave about their reignited sex lives. SummaryMaintaining youthful cognitive function is a crucial challenge of aging, both in terms of cognitive function and structural deterioration or “brain wasting.” Declining memory function may begin as early as age 30 and is often evident after 50 years of age. Fortunately, it is possible to take proactive steps to maintain youthful cognition with aging. Maintaining a healthy body weight and body fat percentage may help preserve healthy brain structure and function. Frail bones have been linked with cognitive decline in women. Hormonal balance may promote healthy cognitive function. Traumatic brain injury is a common yet overlooked cause of cognitive difficulties. Exercise increases blood flow to the brain and may decrease the risk of cognitive decline, while promoting healthy sleep. A healthy diet and extra nutritional support further enhance cognitive function. If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.
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