New Study Suggests a Healthy Diet May Not Reduce Dementia Risk

The results of a new study pub­lished in the Journal of the American Medical Association (JAMA) sug­gested that a healthy diet does not reduce demen­tia risk.

These find­ings con­tra­dict ear­lier stud­ies which con­cluded that a healthy diet reduces the risk of men­tal decline and helps to pre­vent abnor­mal­i­ties that can pre­cede demen­tia.

In this first-ever study to eval­u­ate the long-term effects of diet on the risk of devel­op­ing demen­tia, par­tic­i­pants’ eat­ing habits were observed from mid­dle-age with fol­low-ups con­tin­u­ing for 25 years. The research team mon­i­tored 8,200 mid­dle-aged adults, of which 344 were even­tu­ally diag­nosed with demen­tia.

There was no marked decrease in the onset of demen­tia between the 30 per­cent of par­tic­i­pants who stuck to a healthy diet rich in; fruit, veg­eta­bles, whole grains, nuts and legumes and con­sumed unsat­u­rated fats includ­ing olive oil and the 30 per­cent with a poor diet that who reg­u­larly con­sumed red meat and ate sugar-rich foods.

The study was car­ried out by a team from the French National Research Institute (INSERM). Ironically, lead researcher Tasnime Akbaraly pub­lished a study in 2018 which con­cluded that a healthy diet could help pre­vent the onset of depres­sive orders as well as con­tribut­ing to over­all health and well­be­ing.

The Alzheimer’s Association, who are them­selves cur­rently spon­sor­ing a trial look­ing into the effects of dietary changes along with other pre­ven­ta­tive mea­sures for older adults at risk of men­tal decline, have con­tin­ued to advise that eat­ing a heart-healthy diet low in sat­u­rated fats is ben­e­fi­cial to men­tal and phys­i­cal health.

While they have stated on their web­site that fur­ther research is needed on the rela­tion­ship between diet and cog­ni­tive func­tion they have advised that the Dietary Approaches to Stop Hypertension (DASH) and the Mediterranean diet are con­sid­ered to be ben­e­fi­cial in reduc­ing the risk of demen­tia.

“I would cer­tainly not want any­one to come away from this think­ing a healthy diet is futile,” Keith Fargo, direc­tor of sci­en­tific pro­grams and out­reach at the Alzheimer’s Association, told Health Day. ​“This study has to be viewed within the con­text of the larger sci­en­tific lit­er­a­ture on diet and cog­ni­tion, which does sug­gest there’s a ben­e­fit [from healthy eat­ing].”

Fargo believes that clin­i­cal tri­als give more defin­i­tive answers.

“Studies like this one which exam­ines lifestyle habits can­not answer the ques­tion, will chang­ing my diet reduce my risk of demen­tia, because they do not prove cause and effect,” he said. ​“You can’t rely on obser­va­tional stud­ies like this to tell you what to do.”

Earlier this year, Olive Oil Times reported that key nutri­ents of the Mediterranean diet were asso­ci­ated with healthy brain aging.

• JAMA


• Healthy Day


• National Center for Biotechnology Information