Dietary Antioxidants Don’t Protect Against Dementia Or Stroke
A new study, led by Elizabeth Devore at Harvard’s Brigham and Women’s Hospital, has determined dietary antioxidants such as beta-carotene and vitamin E may not reduce the risks of developing progressive neurological conditions.
The goal of the Harvard Medical School study was to evaluate total antioxidant capacity of the diet — measured by the ferric-reducing antioxidant power (FRAP) assay — in relation to dementia, stroke, and key structural brain volumes in the elderly, essentially observing how antioxidants and major neurologic outcomes in older adults are linked.
The research used a Rotterdam Study model, which is a population-based cohort study typically applied when investigating factors and determining the occurrences of cardiovascular, neurological, and psychiatric diseases in elderly people.
A cohort is a group of people who share a common characteristic or experience within a defined period. A cohort study is an observational analysis of risk factors. A group of people who do not have the target disease are studied, and correlations are used to determine the absolute risk.
The observational model — frequently used in medicine, social and actuarial science, and ecology — studied 5,395 participants who were 55 and older and dementia free. Dietary information was provided in order to establish a baseline from semi-quantitative questionnaires and FRAP measurements.
After five years, an MRI brain scan was performed. Of the study subjects, 5,285 were still stroke free, and 462 were both dementia and stroke free.
The resulting data was published by Neurology. Researchers concluded the total antioxidant capacity of the diet, measured by dietary FRAP scores, did not seem to adequately predict risk or prevention of major neurologic diseases. Dietary antioxidants did not make enough of an impact to be negligible.
Dementia is a loss of brain function that occurs with a comorbidity of diseases like Huntington’s, multiple sclerosis, and Parkinson’s where the cells of the brain are damaged. Memory, language, judgment, reasoning, planning, and behavior and personality are affected. In most cases, dementia is considered a degenerative, persistent disease. Therefore, the condition worsens over time.
Dementia originates in the cerebral cortex of the brain, which accounts for approximately two-thirds of the brain’s mass. It controls crucial sensory and cognitive functions. At the onset of dementia, the four lobes of the cerebral cortex begin to deteriorate.
Symptoms can manifest as mild cognitive impairments, which are casually disregarded as normal forgetfulness. These can include the inability to focus and perform more than one task, taking an inordinately prolonged amount of time to perform activities, forgetting recent events and conversations, misplacing items, and frequently getting lost on familiar routes.
Depending on the type of dementia, the person’s behavior may eventually become out of control. The person may become angry, agitated, and combative. They may also come off afraid, clingy, and childlike.
Vascular dementia has similar symptoms and is caused by brain damage from impaired blood flow to the brain; a stroke. Lewy body disease is a leading cause of dementia in elderly adults. People with this condition have abnormal protein structures in certain areas of the brain. Alzheimer’s disease (AD) is the most common type of dementia.
Dementia usually occurs in old age. Thus, the risk for dementia increases as a person gets older. It is rare in people under the age of 60. When dementia does appear prematurely, it is called early onset AD.
Over time, as the disease ultimately advances, those afflicted with progressive neurological conditions require monitoring and potentially palliative care. Monitoring is often done within the confines of facilities with professionals trained to interact and care for someone dealing with degenerative dementia.
Palliative care is medical care provided by provided by a team of doctors, nurses, and other specialists. Similar to hospice care, the focus is relieving and preventing unnecessary pain and stress on patients with a serious chronic illness.
How quickly dementia progresses will depend on the cause and the area of the brain affected. Some types of dementia advance slowly over several years. Other types may progress more rapidly. If vascular dementia is caused by a series of small strokes, the loss of mental skills may be gradual. If it is caused by a single stroke in a large blood vessel, loss of function may occur suddenly.
[Image via Shutterstock]