Research from Japan’s Kyushu University Medical School has found that dementia and Alzheimer’s disease are associated with type 2 diabetes. Because type 2 diabetes has also been linked to poor nutrition and lack of exercise, dementia and Alzheimer’s can now be linked directly to diet and exercise.
The researchers, from the Graduate School of Medical Sciences’ Environmental Medicine Department, followed 1,017 adults over the age of 60 years old for fifteen years. The elderly adults lived in an adult community and were dementia-free at the beginning of the study.
The adults were given oral glucose tolerance tests periodically. At the end of the fifteen years, those the adults whose glucose tolerance testing confirmed a diagnosis of diabetes by the end of the study were more than twice as likely to have Alzheimer’s disease, and 74% increased incidence of vascular dementia.
Dementia and Alzheimer’s disease risk also significantly increased among those whose two-hour post-load glucose levels were over the 7.8 mmol/Liter levels, and the highest risk was found among those with two-hour post-load glucose levels over 11 mmol/Liter.
The study was published in the medical journal Neurology, and has been coined the Hisayama Study.
The researchers concluded that, “Our findings suggest that diabetes is a significant risk factor for all-cause dementia, Alzheimer’s disease, and probably vascular dementia.”
A number of studies have linked type 2 diabetes with diet and exercise.
In a study from the Britain’s University of Bristol studied 593 type 2 diabetes patients, and found that while the control group (no diet or exercise regimen) worsened over a six month period, those who who underwent diet therapy had 28% increased glycemic control, and those who underwent diet and exercise therapy had 31% increased glycemic control after six months.
A German study found that 90 minutes a week of vigorous aerobic exercise or 150 minutes per week of moderate-intensity aerobic exercise dramatically decreased diabetes risk.
Other diabetes and metabolic syndrome studies have showed similar findings, and these subsequently clearly link diet and exercise to the risk of Alzheimer’s disease and dementia.
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Geidl W, Pfeifer K. Physical activity and exercise for rehabilitation of type 2 diabetes. Rehabilitation. 2011 Aug;50(4):255-65.
Andrews RC, Cooper AR, Montgomery AA, Norcross AJ, Peters TJ, Sharp DJ, Jackson N, Fitzsimons K, Bright J, Coulman K, England CY, Gorton J, McLenaghan A, Paxton E, Polet A, Thompson C, Dayan CM. Diet or diet plus physical activity versus usual care in patients with newly diagnosed type 2 diabetes: the Early ACTID randomised controlled trial. Lancet. 2011 Jul 9;378(9786):129-39.