Alzheimer’s disease (AD) is a chronic neurodegenerative disease that usually starts slowly and gradually worsens over time. It is the cause of 60 – 70% of cases of dementia. The most common early symptom of AD is difficulty in remembering recent events. As the disease progresses, symptoms can include problems with language, disorientation, mood swings, loss of motivation, lack of self care, and behavioral issues. About 70% of the risk is believed to be inherited from a person’s parents. The disease process is associated with amyloid plaques and neurofibrillary tangles in the brain. A probable diagnosis is based on the history of the illness and cognitive testing, along with medical imaging and blood tests to rule out other possible causes. Currently, there are no medications or supplements, to date, that have been shown to decrease risk.
As we age, the hippocampus, an area of the brain located in both hemispheres, plays an important role in maintaining short-term and long-term memory. Generally, the ends of our chromosomes- called telomeres -become shorter with stress. Thus people are more vulnerable to disease. Shorter telomeres are also related to health issues, such as memory loss.
Hippocampus volume (HV) loss is already the most common problem among older adults. Those with AD suffer from further decrease of this volume. However, the are ways to increase this volume. Scientific studies observed that yogāsana, aerobic exercise training and meditation, were effective at reversing hippocampal volume loss in late adulthood.
Telomere length (TL) shortening has also been observed in age-related neurodegenerative diseases, including AD. Telomeres, at the ends of chromosomes and strands of genetic material, become shorter as cells divide in the process of aging. Telomere length has been considered as a biological marker of age, and it has been demonstrated that its shortening has been associated with cognitive impairment, amyloid pathology and hyper-phosphorylation of tau in AD. It also plays an important role via oxidative stress and inflammation.
A new study provides evidence, for the first time, of a causal relationship between TL and AD, say investigators from Sweden. “This is the first study addressing the causal effect of TL on AD,” principal investigator Sara Hägg, PhD, (docent of molecular epidemiology, Karolinska Institutet, Stockholm) explains.
Meditation (dhyāna) and yogāsana practiced at least two hours per week resulted in less atrophy in parts of the brain and better brain connectivity than those in the control group. Research on the effects of meditation on preserving memory and cognitive functions is still in early stages. While this is the latest study on the correlation between AD and meditation, the brain boosting benefits of meditation have been shown repeatedly.
Through various studies, researchers have found that meditation protects our brain by increasing protective tissues. Meditation can help seniors feel less isolated and lonely. In addition, meditation helps participants feel calmer, lessening perceived stress by reducing the hormone cortisol. Prolonged exposure to cortisol has been known to increase the risk of developing dementia. Lastly, meditation increases cortical thickness and grey matter which slows the aging rate of the brain. Whats more, cortical thickness has been associated with decision making and memory.
Another study has found that intense concentration and relaxation could lead to a growth of new brain cells, protecting against the brain shrinkage and against slowing cognitive function. An international team of scientists evaluated brain scans of 50 U.S. men and women who meditated regularly and brain scans of 50 who did not, and found a startling difference. Generally speaking, the brain scans of those who did not meditate showed a brain age the same as the person’s actual age. However, the brains of people who meditated were on average, 7 years younger than the person’s actual age.
Researchers also acknowledge that people who meditate more regularly may lead healthier lifestyles in general so the effects of meditation on brain health are hard to isolate. The study was recently published in NeuroImage.
“In a way, both yogāsana and meditation are ‘brain exercises’ that engage different parts of the brain based on components of the practice (breathing, mindful movement, exacting postures, chanting, visualization, concentration). Such practices can help the brain form new connections and recover from injuries, in other words, stimulate neuroplasticity,” says Helen Lavretsky, M.D., M.S., director of the late-life mood, stress, and wellness research program at the Semel Institute for Neuroscience and Human Behavior at UCLA.
Lavretsky noted that in both of the aforementioned studies, yogāsana and meditation were used in combination with other approaches, such as exercise, music therapy, medications, and brushing of the teeth. However, she says “ practice and meditation may be helpful in prevention of dementia (a general term for loss of memory and other intellectual abilities serious enough to interfere with daily life) in several ways. “Chronic stress and related stress hormones could negatively affect brain structures important for memory and cognition, like the hippocampus.”
“Chronic stress is also associated with inflammation in the body and in the central nervous system/brain that is linked to AD and other disorders of aging. Yogāsana can reduce stress hormones and inflammatory factors, as well as, teach an individual how to cope more effectively (over time) and protect the body from going through the stress response,” Lavretsky explains, noting that the younger you are when you start practicing yogāsana and meditation, the better.
Caregivers of patients with AD and dementia, who are often under a tremendous amount of stress, may also benefit from yogāsana and dhyāna (meditation), especially when it comes to overall well-being and depressed mood. “A growing number of studies including ours are showing positive brain and cognitive changes with practice, as well as benefits in longtime meditators compared to novices,” Lavretsky says.
Additionally, another study demonstrated that in experienced yogāsana practitioners, brain GABA levels increased after a session. This suggests that the practice of yogāsana should be explored as a treatment for disorders with low GABA levels, such as depression and anxiety.
To sum it up, certain studies find that gray matter volume increase is higher for those who practice haṭha yoga postures (āsanas), prāṇāyāma, and meditation (dhyāna) together. Also, know that yogāsana and Prana exercises (pranānāyāma) increase brain-derived neurotrophic factor (BDNF), a neuroprotective chemical. Yogāsana and exercise, likewise, increase regional blood flow and help enhance neural connectivity to the hippocampus.
Furthermore, poor dental health (already known to influence heart health) likely plays a role in developing AD. Researchers in the UK discovered the presence of the bacterium Porphyromonas gingivalis in the brains of patients who had dementia, when they were alive. This germ is usually associated with chronic periodontal (gum) disease.
Bear in mind that those with a healthy diet, Japanese, or Mediterranean, seem to have a reduced risk of AD. Those who eat a diet high in saturated fats and simple carbohydrates (mono- and disaccharide) have a higher risk. A high-carb diet, and the attendant high blood sugar, are also associated with cognitive decline. Gluten and casein, known to be inflammatory, need to be kept to a minimum. One way to mitigate any damage already done is to increase the amount of fresh fruits and vegetables at every meal.
Gluten proteins have low nutritional and biological value, and grains that contain it are not essential. As for dairy (casein), grass fed cows produce milk that is higher in anti-inflammatory Omega 3s, beta carotene, phytocemicals/antioxidants and conjugated clinic acid. Cows that are fed more varied diets produce milk with higher levels of inflammatory fats and lower levels of vitamins and antioxidants.
Glutamate (an excitatory neurotransmitter of the nervous system) when in excessive amounts in the brain, can lead to cell death through a process called excitotoxicity which consists of the overstimulation of glutamate receptors. Excitotoxicity occurs not only in AD, but also in other neurological diseases such as Parkinson’s and multiple sclerosis. Significant amounts of free glutamic acid are present in a wide variety of foods, including cheeses and soy sauce. Glutamic acid often is used as a food additive and flavor enhancer in the form of its sodium salt, known as monosodium glutamate (MSG).
Finally, it is rarely known that fungal infections can be found in the brain of those with AD. Microbiologist L. Carrasco’s group found statistical correlation between disseminated mycoses and AD. Further work revealed that fungal infection is present in different brain regions of AD patients, but not in the control individuals. A fungal infection may very well explain the symptoms observed in AD patients, but not in the col individuals. The slow progression of AD fits with the chronic nature of some systemic fungal infections, which can be asymptomatic and thus, go unnoticed and untreated. Further work on fungal infections and AD needs to be done. Regardless, remove all fungus and its spores from your home, but be very careful how you do it.
Yogāsana increases the volume of the hippocampus in elderly subjects: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3768219/
Rafael Durán 