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Life Extension Magazine October 2011
Report

Combating Age-Related Brain Deterioration

By Eric R. Braverman, MD, with Dale Kiefer, BS

Strategies for Preserving and Enhancing Brain Function

Scientists 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

Traumatic Head Injury: A Word of Caution
Strategies for Preserving and Enhancing Brain Function

The National Football League (NFL) is just beginning to address the long-term effects on its players of countless head injuries sustained over the years on the gridiron. Meanwhile, prime-time television dramas would have us believe that knocking a person unconscious is a humane, relatively harmless (and remarkably common) way to neutralize a bad guy. But the reality is quite different. Retired boxers who can barely speak are a better example of the effects of repeated head blows.

The NFL’s struggle with the issue is only the latest instance in which the media have focused, however fleetingly, on the dangers of traumatic brain injury (TBI). TBI is far more pervasive—and considerably more dangerous—than people imagine, or television dramas portray.

It is estimated that from 1.4 to 3.8 million Americans sustain TBIs each year, although many injuries go unreported.32,33 TBI encompasses sports-related concussions and repetitive head traumas. Symptoms may include loss of memory, sluggish reactions, aggressiveness, apathy, impulsiveness, reduced intellect, etc. It is a misconception that concussion is reliably signaled by unconsciousness.

Brain scans using magnetic resonance imaging (MRI), positron emission tomography (PET), or computed tomography (CT) are capable of detecting massive injuries, but many TBIs are missed by these methods due to the initial subtlety of symptoms. At PATH Medical, we evaluate brain function using a much broader range of assessments, including tests of brain electrophysiology, memory function, attention function, personality temperament and type, etc. If you suspect you or your child may have sustained a traumatic brain injury, never hesitate to seek professional evaluation and treatment.

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

Causes of Dementia*48

Many medical conditions can contribute to dementia. These include:

  • Alzheimer’s disease
  • Vascular dementia
  • Hormone or neurotransmitter deficiencies/imbalances
  • Toxic disorders

­–Alcoholism/drug abuse/intoxication
­–Heavy metal intoxication (e.g., lead, mercury, etc.)

  • Vitamin deficiencies especially B vitamins (B1 [thiamine], B3 [niacin], B12)
  • Organ failure or dysfunction

­–Hypothyroidism
­–Hypo- and hyperparathyroidism
­–Kidney failure
­–Liver failure
­–Respiratory failure

  • Chronic infections

­–HIV
­–Neurosyphilis
­–Tuberculosis
­–Prion diseases

  • Head trauma

­–Boxer’s syndrome
­–Traumatic brain injury (e.g., concussion)
­–Chronic subdural hematoma

  • Neoplastic conditions

­–Primary brain tumor
­–Metastatic brain tumor

  • Psychiatric disorders

­–Depression
­–Schizophrenia

  • Degenerative diseases

­–Huntington’s disease
­–Amyotrophic lateral sclerosis (ALS or Lou Gehrig’s disease)
­–Multiple sclerosis
­–Dementia with Lewy bodies

*This list is not intended to be comprehensive

The Power of Neurogenesis: New Brain Growth and Life

When 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.

The Power of Neurogenesis: New Brain Growth and Life

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 Sleep

One 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 Libido

A 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.

Robust Brain Function, Robust Libido

Summary

Maintaining 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® Health Advisor at
1-866-864-3027.

Strategies for Preserving and Enhancing Brain Function
Strategies for Preserving and Enhancing Brain Function

Exercise

Exercise is crucial for preserving and even enhancing brain function as we age.

  • Exercise increases cerebral arterial blood flow.46,64
  • Exercise promotes angiogenesis and stimulates neurogenesis in the adult hippocampus.50
  • Exercise promotes production of beneficial brain proteins called neurotrophins.65,66
  • More muscle equates with better cerebral arterial blood flow, and thus better cognition.

Healthy Diet

A healthy diet forms the foundation for successful aging. Diets high in saturated fat and cholesterol are significantly linked to an increased risk of dementia.67,68 In contrast, diets high in omega-3 oils and olive oil (found in the Mediterranean diet) are linked to a significantly reduced risk of dementia.69-71

Follow the antioxidant-rich “Rainbow Diet,” which is nutrient-dense, not calorie-dense.49 The Rainbow Diet is low in sodium and saturated fat and high in fiber. It is also anti-inflammatory. As its name implies, the Rainbow Diet emphasizes the consumption of a wide range of foods in all colors of the rainbow. White foods are excluded from this diet, with the exceptions of yogurt and egg whites.49

Bioidentical Hormones*

Levels of many hormones decline with advancing age. It is possible to restore the body and mind to youthful vigor by re-establishing and maintaining youthful levels of these crucial hormones, under the supervision of a qualified physician. Some are available as supplements (e.g., DHEA, melatonin, vitamin D3), while others require a doctor’s prescription and supervision.49

  • Dehydroepiandrosterone (DHEA)/DHEA-S
  • Erythropoietin
  • Estradiol
  • Human growth hormone (HGH)
  • Insulin-like growth factor (IGF)
  • Insulin
  • Melatonin
  • Parathyroid hormone
  • Pregnenolone
  • Testosterone
  • Vitamin D3

Dr. Braverman’s Nutrient Recommendations

Nutrients are essential tools for keeping your brain young and fit. They are capable of increasing your brain power and processing speed, while simultaneously addressing specific adverse conditions throughout the rest of the body.49

  • Omega-3 fatty acids (fish oil): 2,000-6,000 mg/day (containing a minimum of 1,400 EPA and 1,000 mg DHA)
  • Vitamin D3: 2,000-10,000 IU/day
  • Coenzyme Q10: 100-300 mg daily
  • Resveratrol: 250-500 mg daily
  • Vitamin C: up to 4,000 mg daily
  • B complex: 50-100 mg daily
  • Acetyl-L-carnitine: up to 1,500-3,000 mg per day
  • Acetyl-L-carnitine arginate: 1,000 mg per day
  • R-lipoic acid: 150-400 mg daily
  • Phosphatidylserine: 100-200 mg per day
  • Ashwagandha: 250 mg per day
  • Vinpocetine: 15-30 mg per day
  • Alpha-glycerylphosphorylcholine (GPC): 600 mg per day
  • Zinc: 30-90 mg/day (Editor’s note: Individuals supplementing with more than 50 mg of zinc should take at least 2 mg of copper daily.)
  • Vitamin K2: 100 mcg to 2,100 mcg daily

Drug Therapy

Certain prescription therapies may promote more successful aging.

  • Antihypertensive therapy. Evidence suggests that antihypertensive drugs may help reduce the risk for, and progression of, dementia.72
  • Antidepressants. Modern antidepressants increase neurogenesis and preserve neurotransmitters 73,74

*(For a complete list, see my book, Younger You)49

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