New double-blind study confirms benefits of 'strawberry therapy'
Recently, scientists have described the many positive health effects of strawberries for people 66-78 years old. Now another team of researchers tested the effect of "strawberry therapy" on less elderly participants - 50-65 years old. Based on the results, the experts concluded that the presence of strawberries in the diet at this age is important for reducing the risk of dementia.A lot is known about the beneficial properties of strawberries: it is a source of many bioactive compounds, including anthocyanins. A one-cup serving of strawberries provides 100% of people's daily vitamin C needs. It also contains essential heart-healthy nutrients such as folic acid, potassium, fiber, phytosterols and polyphenols.
The new double-blind, placebo-controlled study using strawberries was conducted by researchers at the University of Cincinnati Academic Health Center and the Schubert Clinic at Cincinnati Children's Hospital Medical Center (USA). The work was published by the journal Nutrients.
Twenty-five women and five men between the ages of 50 and 65 who were overweight and complained of mild cognitive decline were recruited to participate. The people were divided into two groups. Participants in the first group, which included 15 women, received 13 grams of dried and freeze-dried strawberry powder made from whole fruits every day for 12 weeks. According to the researchers, this dosage is equivalent to about one cup of whole fresh strawberries. The second group, which included 10 women and five men, was given a placebo - an imitation strawberry powder without the beneficial polyphenols.
Before the experiment began and at its conclusion, the participants underwent examinations focusing on neurocognitive function and mood measures. In addition, the scientists assessed metabolic and anthropometric parameters and collected dietary data three days before and after the study. People were also asked to avoid all berries and foods containing berries for 12 weeks to ensure there was no impact on the results.
After almost three months of strawberry therapy, the researchers noted a number of positive changes in the participants who used strawberry powder compared to the placebo group. When performing the California Verbal Learning Test, the former made fewer errors, indicating improved learning and memory processes. In addition, the results of the questionnaires revealed that the people had reduced levels of depressive symptoms when assessed by the Beck Depression Scale. Researchers saw this as a sign of improved ability to cope with emotions.
"The results confirm that adding strawberries to the diet in midlife plays a role in dementia prevention," the study said.
However, evidence of a positive effect of strawberries on metabolic parameters could not be found. According to experts, this may be due to the small sample size, the short duration of the experiment and the relatively small dose of anthocyanins that came with strawberry powder.
The scientists concluded that to assess the benefits of strawberries on cognitive and metabolic functions in the context of aging, larger and longer studies with larger samples of subjects and different dosing regimens are needed.