Healthy Living

The Link Between Alzheimer’s Disease and Obesity

The Link Between Alzheimer’s Disease and Obesity

Obesity has become a worldwide phenomenon. Statistics show that a third of the world’s population is either obese or overweight. Ranked with the most number of obese people, US, China, India, Russia, and Brazil top the list. But, what does this list really tell people? It’s simple—too much weight means one has an excess of fat tissue, and this could have serious health consequences.

When a person’s Body Mass Index (BMI) exceeds a particular threshold relevant to one’s height and weight, one becomes at risk of certain diseases. This includes cancer, arthritis, kidney diseases, cardiovascular diseases, and diabetes. Recent studies have also found a connection between the condition and Alzheimer’s disease.

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Experts warn that if the trend continues, the rate of Alzheimer’s development in the population will continue to skyrocket. As of today, more and more people suffer from it due to the increasing number of overweight or obese individuals.  

Importance of Insulin in Brain Functioning

As food is consumed, the body’s pancreas releases a hormone called insulin to convert carbohydrates to sugar (glucose). This is what the body uses for energy and stores for future use. When a person’s weight increases, they may develop insulin resistance even if they are not obese or overweight, which interferes with insulin’s metabolic effects. This resistance results in the body releasing more insulin, resulting in organ failure and may further develop into type 2 diabetes.

Previous studies have shown that diabetes, including high blood pressure, increase the risk for Alzheimer. How is this possible? When there is a lot of insulin in the bloodstream, the brain’s energy supply is disrupted as it lowers the amount of glucose that fuels the brain. Thus, the nerve cells in the brain are not able to pass signals to one another. Retaining memories will become difficult to a diabetic or obese individual later in life.

Insulin is important for many of the vital brain functions. Other than helping to preserve long-term memories, insulin affects the energy metabolism of the brain. With insulin, the brain is also able to get rid of toxic amyloid consequently preserving the brain’s overall health.

Alzheimer’s patients benefit from this knowledge on how important insulin is. This is why current treatments now include intranasal insulin wherein insulin is sprayed towards the nasal cavity. This method enables the brain to absorb insulin more easily, which boosts mental functioning. However, this treatment is still not available for patient’s use although it has helped those who are part of research studies.

Weight’s Connection to Alzheimer’s

Every single day, people see ads of fast foods offering unhealthy meals with empty calories. They clearly provide a quick meal but are not very effective in squelching hunger. Worse, they promote overeating and increase the risk for related diseases. Of course, overeating is not the only cause of obesity. Others suffer from medical conditions that increase their chances of contracting it. Take arthritis as an example. People who have it have more difficulty in doing physical exercises, which may result in gaining weight.

As one gains weight, he or she runs the risk for high blood pressure or diabetes. These diseases in return can elevate the risk for Alzheimer’s disease. It is important to note, however, that for some patients the case is the opposite. That is, their weight gain resulted from their cognitive difficulty. It may also be a sign of poor self-care, apathy, or infrequent physical activity.

As surprising as it may seem, Alzheimer’s disease can also be a result of weight loss rather than being overweight or obese. This is true for patients pass mid-life. There is still no clear connection, but this may be due to genetic factors as well. Studies concur, however, that there is a link between Alzheimer’s and weight loss, and a specific Apolipoprotein (APOE) gene. The latter condition cannot only cause trouble to the patients but also to their caregivers. Patients may concern themselves less with mealtimes and self-care. This change in appetite in old age may have a great contribution to the problem.

Research Developments

Alzheimer’s disease affects billions of people worldwide. In the United States alone, there is an estimated 5 million sufferers and is expected to rise to 16 million by the year 2050. The disease is already known as the 6th leading cause of death in the country, outnumbering the patients with breast and prostate cancer combined. This appalling statistic highlights the urgent need for causes or markers that can help identify patients with the risk of contracting the disease. Discovering treatment and prevention strategies are equally important.

There have been numerous studies suggesting an association between obesity and Alzheimer’s disease. However, the main finding centers around the strong connection between mid-life obesity and Alzheimer’s. Studies noted that a high Body Mass Index (BMI) is a strong risk factor increasing the likelihood of late-life amyloid in the human brain. Research institutes add that this may even prompt an earlier inception of the disease.

A study conducted at the National Institute on Aging confirms earlier and other recent studies. It was found that obesity in middle age increases the risk for developing neurofibrillary tangles and amyloid deposits in the brain. This means, Alzheimer’s could have started ravaging the brain far before its first symptoms appear. Among the 1,394 volunteers in the study, 142 of them have developed Alzheimer’s disease.

Dr. Thambisetty, the expert who led the study, stressed that obese people in their middle age should be wary of their lifestyle. Although there was no in-depth study conducted, human lifestyle could possibly contribute to the disease and changes in it will likely address the problem. If it won’t address the problem right on the head, it would decelerate its onset at the very least.

As far as treatments are concerned, the intranasal insulin is most promising. Clinical trials are now in progress but with limited findings. Findings noted that this treatment boosts mental activity— it improved cognition, attention, and the verbal memory of Alzheimer’s patients. Other inhibitors are currently investigated to hopefully lead to treatments.

Current Status of Research in Alzheimer-Obesity Connection

In so far, no long-term studies have clearly shown that obesity in mid-life is linked to Alzheimer’s. What are available are short-term case studies which are not all-encompassing, but are definitely representative of what patients may undergo. Further investigation is needed to tap into the many facets of the Alzheimer-Obesity connection and discover prospective treatments.

Government and non-government funded studies are currently on the go. However, longitudinal studies need not only time but also funding for studies to successfully be conducted. Brain scans, for example, take an enormous amount of money. Thus, researchers are yet to identify the elements clearly establishing the connection between obesity and Alzheimer’s disease.

Final thoughts

Both Alzheimer’s disease and obesity are alarming conditions that need more attention from health officials, patients, and other involved participants. We now know that there is a connection between them, which just needs time to confirm ‘how’ exactly they are linked. It’s just a matter of time as well to find real treatments to these conditions.

However, one thing is for sure: a healthy lifestyle is key to optimal aging and greater quality of life. Have proper exercise and mind your diet at all times. Doing this could significantly lower one’s risk for any disease, not just Alzheimer’s. In due time, this epidemic will soon come to its conclusion.