Strawberries enhance brain speed and heart health, but cognitive benefits remain unclear

Want to sharpen your mind and lower blood pressure? Study reveals how a daily strawberry habit could help—but there’s a catch.

Study: Strawberries modestly improve cognition and cardiovascular health in older adults. Image Credit: Pixel-Shot / Shutterstock

In a recent study published in the journal Nutrition, Metabolism, and Cardiovascular Diseases, researchers investigated whether strawberries improve cardiovascular health and cognition in older adults.

Cardiometabolic diseases elevate the risk of cardiovascular disease and include dyslipidemia, hypertension, abdominal adiposity, and impaired glucose regulation. Cardiometabolic disease risk factors are linked to cognitive decline, and elevated inflammatory cytokines from these diseases may contribute to cognitive impairments.

Strawberry supplementation has been reported to improve tasks mediated by the hippocampus, such as spatial learning, word recognition, and memory in older adults. It is also associated with improved vascular health. Strawberry components promoting health and cognition include vitamins, dietary fiber, antioxidants, polyphenols (anthocyanins, tannins, and other flavonoids), and minerals.

A recent study revealed that specific anthocyanins are neuroprotective, prevent cognitive impairment, and modulate memory and learning. However, the current study did not directly measure anthocyanin levels or bioavailability, leaving their precise role in observed effects unclear. Overall, there is a scientific rationale for strawberries' potential to promote cardiometabolic health and cognition. While studies on strawberries involving older adults exist, their methodologies and findings remain heterogeneous.

About the study

The present study investigated whether strawberries improve cardiovascular health and cognition. They recruited adults aged over 65 with a body mass index (BMI) of 25–40 kg/m² and a willingness to consume two beverages over two periods. Participants were generally healthy at baseline, with normal blood pressure and no cognitive impairments. Individuals with supplement use, psychiatric medication use, metabolic disorders, smoking, or coffee intake were excluded.

At baseline, a medical history questionnaire and the food frequency questionnaire (FFQ) were administered at each visit. In a randomized, placebo-controlled crossover design, participants attended four laboratory visits over five months. After an initial eight-week phase, they underwent a 4-week washout period before switching to the second eight-week treatment.

Participants were randomized first to consume a control beverage (matched for macronutrients but lacking polyphenols) or freeze-dried strawberry beverage. The freeze-dried strawberry dose was equivalent to two servings of fresh strawberries. The primary outcome was cognitive measures, and the secondary outcome was cardiovascular risk factors. Subjects were asked to fast overnight before each visit.

At the baseline visit, height was recorded, and a mini-mental state examination (MMSE) was administered. Participants had a mean MMSE score of 29 (near the maximum of 30), indicating high baseline cognitive function. After a flow-mediated dilation (FMD) test and blood sampling, participants consumed a standardized muffin. Subsequently, the cognition battery of the National Institutes of Health (NIH) toolbox was administered.

These tests were repeated at each subsequent visit. Cognitive tests included the list sorting working memory test (LSWMT), pattern comparison processing speed test (PCPST), picture sequence memory test (PSMT), flanker inhibitor control and attention test (FICAT), and dimensional change card sort test (DCCST).

Findings

In total, 35 individuals were included in the analyses. Participants’ weight and BMI were not significantly different over time and between phases. There was a main effect of reducing total flavonoid intake in the background diets (lacking study beverages). Notably, the study did not isolate or quantify specific flavonoids like anthocyanins, focusing instead on total flavonoid intake. Further, no significant differences were observed over time and between phases for carbohydrate, energy, protein, fiber, fat, potassium, and sodium in background diets.

Notably, no significant differences were observed between phases or over time for executive function (DCCST), working memory (LSWMT), and attention and executive function (FICAT). However, a time effect of PCPST was detected, and post-hoc tests indicated processing speed improvements in the strawberry phase.

In addition, time effect and time–phase interaction were noted for PSMT, and post-hoc tests indicated better episodic memory in the control phase. The researchers found no significant differences between phases and over time for total cholesterol, blood glucose, high- or low-density lipoprotein cholesterol, diastolic blood pressure, C-reactive protein, and insulin.

Total antioxidant capacity decreased in the control phase and increased in the strawberry phase. Triglycerides showed a time effect, increasing in the control phase but remaining within healthy ranges. Systolic blood pressure showed a time-phased interaction, decreasing in the strawberry phase but with no significant differences in the control phase. FMD showed no significant differences between phases or over time.

Conclusions

The findings illustrate modest improvements in cognitive processing speed and systolic blood pressure with strawberry supplementation. The study’s authors suggest polyphenols like anthocyanins and ellagitannins in strawberries may drive these effects, though the lack of direct anthocyanin measurement limits mechanistic certainty. In contrast, episodic memory unexpectedly improved in the control phase; strawberry consumption did not affect FMD. Taken together, strawberry consumption caused minor changes in cognition, a modest reduction in blood pressure, and improvements in antioxidant status. However, the study’s short duration (8 weeks per phase) and healthy participant pool limit broader conclusions for individuals with existing cardiometabolic or cognitive conditions.

Funding/Disclosure

This study was funded by the California Strawberry Commission. The authors declared no conflicts of interest.