Holding to Mediterranean Diet Lowers Parkinson’s Risk for Women, Study Finds

Women who adhere closely to a Mediterranean diet in their 30s and 40s have a lower risk of Parkinson’s disease later in life, particularly once they reach their mid-60s, a large population-based Swedish study found.

The study, “Mediterranean Dietary Pattern at Middle Age and Risk of Parkinson’s Disease: A Swedish Cohort Study,” was published in the journal Movement Disorders.

Diet is increasingly recognized for its potential influence on a person’s risk of several diseases. With Parkinson’s, for instance, studies have suggested that dairy products could be a risk factor for its development.

The Mediterranean diet, which is rich in vegetables, fruits, legumes, grains, fish, and unsaturated fats like olive oil, and low in  meat and dairy foods, has been proposed to protect against the neurodegeneration that marks disorders like Parkinson’s, as well as other types of disease, including cancer.

Researchers at Karolinska Institutet and colleagues conducted a large Swedish population-based study to assess if adherence to a Mediterranean diet may lower the risk of Parkinson’s for older adults.

They evaluated the dietary habits of 47,128 women who, when they were between the ages 29 and 49, had participated in the Women’s Lifestyle and Health study. This population study, which ran from the 1990s to 2000s, aimed to determine whether a Mediterranean diet could affect overall and cancer mortality.

In the Karolinska study, these women were asked to recall their dietary habits in the six months before enrolling, using a food frequency questionnaire that contained a list of 80 different foods that are part of the Mediterranean diet. Adherence to the Mediterranean diet was scored from zero (lowest adherence) up to nine (highest adherence).

“[D]ietary habits seem to be a lifelong behavior and are not very dynamic,” the researchers noted.

The scientists then crossed diet information — on the 41,715 women who answered the food questionnaire and were eligible — with clinical data from the Swedish National Patient Register to identify those diagnosed with Parkinson’s during this study’s median 10.9 years of follow-up.

Women followed were at least 50 years old, as this is a common starting age for a Parkinson’s diagnosis.

A total of 101 women were diagnosed with Parkinson’s during those years of follow-up.

Results showed that women with high adherence to the Mediterranean diet — food choice scores of six to nine — had a 46% lower risk of developing Parkinson’s, compared with those with low adherence (scores of zero to three). This was particularly noticeable among women 65 or older, with those adhering strongly to the Mediterranean diet having a 57% lower risk of Parkinson’s compared with those poorly adherent.

A one-unit increase in the diet’s adherence score was linked to a 11% reduction in Parkinson’s risk for the overall group, and to a 29% reduction for those 65 or older.

While the incidence of Parkinson’s tended to increase with age, it rose more quickly for those 65 or older with low diet adherence.

These results suggest that “a higher adherence to the MDP [Mediterranean dietary patterns] at middle age was associated with a lower risk for PD [Parkinson’s disease] later in life,” the researchers wrote.