Certain foods linked to reduced incidence of dementia
FUKUOKA – An ongoing epidemiological study conducted in a small town in Fukuoka Prefecture has shown certain dietary patterns to be associated with reduced risk of dementia.
For about the last half century, residents’ ages and occupations in the town of Hisayama (pop. 8,339 as of July 1), located to the east of the city of Fukuoka, have remained about the same as the national average. For this reason, Kyushu University set up a research lab in town and began conducting an epidemiological study of its population starting in 1961, under the belief that results would reflect the general Japanese population.
Researchers began studying dementia in Hisayama in 1985. According to an analysis of data collected from 1,193 residents aged 60 and older over a period of 17 years, the rate by which seniors developed dementia in their lifetime was found to be about 55 percent.
For 17 years, the research team tracked the diets of 1,006 people aged 60 to 80 who did not show symptoms of dementia at the beginning of the study. Of these subjects, 271 developed dementia — of which 144 had Alzheimer’s and 88 had vascular dementia. Kyushu University researcher Mio Ozawa looked into the links between the onset of dementia and the amount of foods such as rice, bread, noodles, potatoes, soybeans and miso that was consumed.
Ozawa and her team found that a diet abundant in vegetables, dairy and soybean products and low on rice was associated with a reduced incidence of dementia. Researchers also indicated numerically the impact that certain foods have on dementia prevention. The figures show that it is better to cut back on rice, but a study of rice on its own does not show any links between the food itself and the onset of dementia.
“When one eats more rice within a diet that can only contain so many calories, the more rice one eats, the less vegetables and other foods one can fit,” Ozawa explained, “which may be why increased rice consumption is linked with an increased likelihood of developing dementia.”
As for milk and other dairy products, which made the list of foods whose intake should be increased, the researchers found that the calcium and magnesium found in dairy products were effective in preventing dementia. Dairy also contains an abundance of vitamin B12, which has the effect of reducing homocysteine levels, which are believed to raise the risk of Alzheimer’s; consumption of dairy reduced the incidence of dementia, including Alzheimer’s, the researchers said.
“There are no established treatments for dementia, nor are there any preventative drugs for dementia,” said Yutaka Kiyohara, head researcher of the Hisayama Study. “We hope to help prevent the disease by understanding the reality of dementia through epidemiological research and shedding light on the risk factors.
Epidemiological studies rely on statistics to identify the relationships between the causes and outbreaks of disease. Hisayama residents 40 years old and older are eligible for Kyushu University’s Hisayama Study, which is carried out as a collaborative effort between Kyushu University and local doctors, and at least 80 percent comply. With the help of the municipal government, researchers continue to seek the cooperation of those who have moved outside the town’s borders, with about 99 percent success. Some 80 percent of residents agree to autopsies, allowing researchers to identify diseases and causes of death. As a result, the study is considered unparalleled around the world. Specialists make diagnoses in the case of dementia, too, and autopsies confirm dementia in many cases.
Source: Mainichi
Published: 27 July 2014
Category: Features, Wellness and Complementary Therapies
