Berries have long been appreciated for their delicious flavor and appealing appearance. Among them, the blueberry stands out for the growing scientific attention it receives, as researchers explore its potential health benefits.
Rich in vitamins, minerals, dietary fiber, and polyphenols—especially anthocyanins—blueberries are considered valuable allies for well-being and reducing the risk of chronic diseases.
To take stock of current research and identify gaps and future directions, a group of scientific experts gathered for a roundtable discussion focused on the health benefits of blueberries.
The discussions covered five key areas: cardiovascular health, pre-diabetes and type 2 diabetes, brain and cognitive health, gut health, and recovery from physical exercise.
This article summarizes the results of that discussion, offering a deep dive into the current scientific evidence and future perspectives for this extraordinary berry.
Blueberries and Cardiovascular Health
Much of the research on blueberries has focused on cardiovascular health. Large population studies suggest that high habitual intake of berries, including blueberries (e.g., >3 servings per week), is associated with a reduced risk of myocardial infarction and hypertension.
In particular, higher habitual anthocyanin intake has been linked to a significant reduction in the risk of heart attacks and hypertension.
Several meta-analyses, which pool data from multiple studies, have shown beneficial effects of blueberries on cardiometabolic markers, such as reduced total cholesterol, LDL cholesterol ("bad" cholesterol), and C-reactive protein (an inflammation marker), as well as a lower risk of coronary heart disease and overall cardiovascular events.
There has been a positive impact on vascular function (blood vessel health), although findings regarding oxidative stress, inflammation, and blood pressure have been mixed.
Clinical Effects and Variability
Randomized clinical trials (RCTs), involving daily blueberry intake for weeks or months, have shown benefits on cardiometabolic markers, with doses equivalent to 1–2 cups of fresh blueberries per day.
Regular blueberry consumption may help reduce blood pressure in sedentary individuals, those with metabolic syndrome, or postmenopausal women with elevated blood pressure.
Both acute and chronic studies have also shown improved vascular function, including endothelial function (the ability of blood vessels to dilate) and arterial stiffness. Anthocyanins and their metabolites appear to be the key mediators of these protective effects.
However, research highlights some heterogeneity in RCT findings, possibly due to differences in study populations, methods, or interventions. More research is needed to examine the long-term effects (>6 months) of daily intake and to understand the individual factors linked to health benefits.
Blueberries and Type 2 Diabetes/Pre-diabetes
Population-based studies suggest that higher habitual intake of blueberries (≥2 servings per week) is associated with a lower risk of developing type 2 diabetes.
However, RCT findings on daily blueberry consumption’s effects on glucose regulation and insulin resistance in adults with dysglycemia (impaired blood sugar regulation) have been mixed.
Some studies showed improved insulin sensitivity in specific groups, while others found no significant changes.
Some trials noted reductions in hemoglobin A1c (a long-term blood sugar control marker) or fasting insulin, and one acute study showed that blueberry intake lowered postprandial glucose and insulin peaks after a high-calorie meal.
Cognitive and Brain Health
Higher intake of berries (including blueberries and strawberries) has been linked in prospective studies to slower cognitive decline, a higher chance of healthy aging (without chronic disease or disability), and a lower risk of Parkinson’s disease. Several scientific reviews conclude that blueberries offer small to moderate cognitive benefits in older adults.
Animal studies have shown that blueberry supplementation improves cognitive performance and may reverse age- or diet-related deficits. Human clinical studies have confirmed cognitive benefits from daily blueberry intake (freeze-dried powder or juice) in both middle-aged and older adults, with intact or mildly impaired cognitive function.
The mechanisms behind these benefits may include improved metabolic regulation (e.g., reduced hyperinsulinemia), enhanced brain activation and blood flow, optimized vascular function, and reduced inflammation and oxidative stress.
Future research should further explore these mechanisms, possibly integrating functional brain imaging, biomarker measurements, and anthocyanin levels.
The Link Between Blueberries and Gut Health
Gut health is an emerging area of interest for berries. While no single definition exists, it generally refers to the absence of gastrointestinal symptoms or disorders and unfavorable conditions.
Few human studies have directly examined blueberries’ effects on functional gastrointestinal disorders. One clinical trial showed that blueberry consumption improved abdominal symptom relief and quality of life in patients with such conditions.
It is known that blueberry polyphenols, particularly anthocyanins, are extensively metabolized by the gut microbiota, suggesting that resulting metabolites may mediate health effects.
In human trials, limited RCTs have shown modest changes in gut microbiota composition after blueberry intake.
Blueberries and Post-Exercise Recovery
Scientific interest has also focused on blueberries’ role in exercise recovery. Many studies have examined the impact of blueberries or anthocyanins on physiological stress markers such as inflammation and oxidative stress.
Although effects on post-exercise muscle soreness are variable, blueberry intake has been linked to a reduction in inflammatory and oxidative biomarkers in blood, particularly following metabolically demanding workouts.
Some clinical studies have found that daily blueberry intake can counter the rise in pro-inflammatory lipid mediators and promote inflammation resolution during recovery.
Despite some inconsistencies, blueberries may help reduce inflammation and support recovery after intense exercise. Future research should refine methodologies and include longer intervention periods.
Toward Guidelines and Recommendations for Berries
The growing body of scientific evidence on the health benefits of blueberries is crucial for shaping future dietary recommendations. While current general guidelines recommend fruit intake, more specific guidance for fruit subgroups like berries—based on type or color—may be beneficial, as different berries offer unique nutritional and phytochemical profiles.
The Nordic Nutrition Recommendations, for example, highlight the importance of including berries in the diet.
It is important to note that most clinical trials have studied the effects of whole blueberries, often in freeze-dried form, which contain a broad range of nutrients and phytochemicals with potential synergistic effects.
The effectiveness and safety of supplements containing only blueberry-derived anthocyanins are not yet well established. For those with limited access to fresh blueberries due to seasonality or perishability, frozen or freeze-dried blueberries are valid alternatives.
The Role of Clinical Research
Currently, there is no consensus recommendation for the specific amount of blueberries to include in the diet. As research advances, more precise, potentially personalized guidelines may be developed based on health status, age, or sex.
Well-designed randomized clinical trials are needed to further strengthen the evidence base for developing dietary and clinical recommendations.
Understanding the effects of different doses, in combination with other foods, within specific dietary patterns and across diverse populations will be key to supporting personalized nutrition approaches.
The research summarized here was supported by the United States Highbush Blueberry Council (USHBC), a research and promotion organization funded by blueberry growers, processors, and importers, operating with independent oversight.
Conclusion: The Potential of Blueberries
Accumulated scientific evidence suggests that blueberry consumption offers promising health benefits in several crucial areas—from preventing cardiovascular disease and diabetes to supporting brain function, modulating gut health, and enhancing physical recovery.
Research continues to explore the complex mechanisms through which blueberries exert their effects, often linked to the actions of anthocyanins and their interaction with the gut microbiota.
Addressing identified research gaps will be essential to broaden our understanding and provide the foundation for specifically including blueberries and other berries in national dietary guidelines and clinical practices.
Regularly integrating berries like blueberries into a balanced diet is a delicious, evidence-based strategy to support long-term wellness, emphasizing their potential role in a modern, health-oriented lifestyle.
Source: Frontiers | The state of the science on the health benefits of blueberries: a perspective via U.S. Highbush Blueberry Council
