Obesity, Physical Activity and Dementia

Obesity, Physical Activity and Dementia

Obesity is on the rise in the United States with an estimated 36.5 percent of adults affected; this means that approximately one-third of the adult population has the condition. Rates are highest among those between the ages of 40 and 59, as well as those over the age of 60. It is widely known that a substantial excess of fat in the body can lead to a host of health troubles, including type 2 diabetes, heart disease, and even some forms of cancer.

For older adults, an inability to maintain a healthy body weight can have an additional consequence; new research has shown a potential link between obesity and cognitive impairment later in life.

A recent study conducted by scientists from the Indiana University Center for Aging Research has revealed a possible connection between a high BMI (body mass index) and a weakened reception to memory training. Researchers observed roughly 2,800 cognitively normal participants over a span of ten years, the majority of whom were white and female with an average age of 74 years. For the duration of the study, scientists compared the degree of progress made by those with a normal BMI, those who were overweight, and those who were obese.

Results indicated that while a high BMI seemed to have little to no impact on reasoning or processing speed training, it significantly affected the benefits a participant gained from memory training; those who were considered obese received approximately one-third the benefit attained by their lower BMI counterparts. Though scientists are not sure exactly how obesity brings such an outcome, Dr. Daniel O. Clark, primary author of the study, referenced imaging studies that showed an association between obesity and a faster loss of hippocampal volume. The hippocampus is the part of the brain that is responsible for memory, and the implication is that older individuals who are obese may not have the same capacity to benefit from memory training as those who have a lower BMI. Dr. Clark also references prior research indicating that safe, intentional weight loss can actually lead to improvements in memory.

While not directly related to obesity, another recent study has found evidence that sedentary adults with no genetic risk factors for dementia have the same likelihood of developing the condition as those who do. Individuals who carry a variant of the genotype “apolipoprotein E” have a greater risk of developing dementia than those who do not, but researchers found that people who are primarily sedentary, but not carriers, exponentially increase their risk by their inactivity.

People who have a sedentary lifestyle, whether by choice or because of a medical condition, may have trouble maintaining a healthy body weight, and prolonged inactivity often leads to obesity. For a variety of reasons, seniors may have greater difficulty fitting exercise into their lives than the young or middle aged; they may have a disability or other impairments that make any physical activity impossible, they may tire more easily, or they may not be able to exercise the way they used to and become discouraged. If they aren’t active or eating well, they will put on weight very quickly, which in turn may put them at an increased risk for dementia.

How can we help our older loved ones build safe, effective exercise into their daily routine?

The good news is that health professionals estimate an intentional weight loss of as little as 5 to 10 pounds can yield significant benefits for a senior. There is no need for strenuous exercise to see at least some improvement. With this in mind, there are plenty of exercise options for those with mobile impairments and those who need a gentler form of physical activity.

There is a post on this blog about the benefits of Tai Chi for the elderly; this thoughtful exercise is perfect for older adults who are still mobile but who may not feel confident in their ability to balance. Tai Chi can also be adapted for seniors who are not secure enough to stand while performing the motions.

Water activities are another great way to get our older loved ones moving again. Walking around in a pool and swimming are forms of exercise that do not strain the joints and free the senior body from the limitations imposed by gravity.

If none of these are feasible, encourage your senior loved one to talk with their doctor about seeing a physical therapist. A physical therapist will help them develop a safe and effective exercise regimen tailored to their level of ability.

All exercise should be approved by your older loved one’s doctor before they add it to their routine.

Having a lower body weight provides a number of benefits to seniors; with fewer pounds to carry, walking is less strenuous. They may feel more alert and more in control of their bodies. Their risk of diabetes and heart disease may decrease. Certainly, the fact that obesity may negatively impact cognitive function is only the newest incentive to maintain a lower weight. Because obesity can lead to and exacerbate multiple severe health issues, it is crucial that we help our parents, grandparents, and older loved ones access the resources they need to keep as active as possible.