Being overweight is rapidly becoming a problem for most Americans. According the Center of Disease Control and Prevention, 33.9% of Americans are obese, while 34.4% of Americans are overweight. That’s an incredible total of 68.3% of Americans who weight more than they should, and a recent study has shown a new health problem associated with mental performance.
While recent focus has been on the effects that excess weight has on the development of diabetes, heart disease, and a host of other problems, this new study brings into focus a whole new set of problems for people who are overweight.
The study was published in Neurology, and followed more than 6,000 people in Britain between the ages of 35 and 55 for over a decade. They consistently took memory tests and had their cognitive skills checked, and people who were obese or had unhealthy metabolic changes were shown to have experienced a faster decline in cognitive skills compared to the other participants in the study.
This study is the first serious disagreement with the recently popular idea that an individual can be obese yet not suffer any health consequences if they avoid developing the symptoms of high blood pressure and diabetes.
"In the last 10 years or so, people started suggesting you could be fit and fat—you could be obese and metabolically healthy and have no health risk," said Archana Singh-Manoux, the primary author involved in the study. She is also the director of research at Inserm, the French National Institute of Health and Medical Research.
Regardless of metabolic health, all individuals experienced the same degree of cognitive decline. "All of these [obese] individuals, whether they were metabolically healthy or not healthy, had a poor cognitive profile," Dr. Singh-Manoux said.
The researchers however were quick to offer up disclaimers. They stated that they were not studying the onset of dementia, but rather simple cognitive decline, and they also stated that the boundary between normal ageing, minor cognitive degradation and dementia is not clear. Further, the test subjects were all taken from the same group of civil service workers, so they may not apply as clearly to other people.
However, within those boundaries the connection was clear. The next step is to examine what role genetics plays, and also to determine the role that the amount of time the people were obese or had these metabolic risk factors played into their more rapid loss of cognitive skills. The researchers were unable to offer an explanation as to why obesity was linked to cognitive decline.
A previous study however that linked Alzheimer’s to diabetic symptoms reveals a possible link. If Alzheimer’s can be considered a form of type 3 diabetes, and displays the same qualities as insulin resistance in the brain, then perhaps a subtle link between weight gain, insulin resistance, and mild form of mental diabetes could be the culprit.
The researchers stated that other studies have shown that performing regular exercise, eating a healthy diet, not smoking, and being aware of your blood pressure and cholesterol levels can stave off the onset of cognitive decline, and should be seen as proactive steps that everybody should engage with. What is clear is that your behavior throughout your life has a cumulative effect on your health in later years, and that the public should be increasingly aware of their health and habits from an earlier age.