The Health Benefits of Blueberries
For a number of years, companies have been marketing the concept of superfoods, specific fruits or vegetables that stand out due to their significant health benefits. Examples include: acai, noni, beets, kale and numerous types of berries among other foods. Berries are typically high in compounds called anthocyanins and proanthocyanidins which have antioxidant and other health benefits. Of the berries, blueberries are exceptionally rich in these compounds.
Research exploring the health benefits of blueberries has increased over the last 20 years. So it’s worth asking, what does the research say? Do blueberries deserve the superfood label?
While more research is needed, there are interesting clinical trials showing potential benefits for:
- Brain function
- Heart disease
- Arthritis
- Preventing diabetes
Blueberries and Brain Function
The latest research appears to support the potential of blueberries for improving aspects of brain function. A recent meta-analysis concluded that blueberries appear to improve memory, although more data is needed (Travica 2020). A number of the clinical trials were single dose studies in children assessing the short-term effects following consumption. One trial showed a blueberry beverage improved memory and focus within two hours (Barfoot 2019). In older adults, blueberries were shown over three months to improve memory and cardiovascular risk factors (Whyte 2018). Some studies suggest benefits of blueberries on mood, although not all research is consistent (Khalid 2017, Travica 2020).
Blueberries and Heart Disease
Heart disease is the number one killer in the United States. Finding safe, effective treatments to reduce heart disease can have a significant impact. A recent study concluded that in patients with metabolic syndrome (a risk factor for heart disease) consuming one cup of blueberries a day can reduce heart disease risk by 12-15%. In subjects that consumed only ½ cup per day, benefits were not seen (Curtis 2019).
Consuming blueberries may also have benefits for blood pressure. A study in postmenopausal women with mild hypertension reduced blood pressure by seven and five points for top and bottom blood pressure numbers respectively (Johnson 2015). A separate study on patients with metabolic syndrome showed reductions of eight and 2.5 points for blood pressure numbers (Basu 2010). Interestingly, other studies showed no benefits for blood pressure. However, these studies used juice or a powdered extract as compared to fresh or freeze-dried whole fruit (Wu 2018).
Blueberries and Arthritis
Blueberries and their constituents have antioxidant and anti-inflammatory effects. In a trial on patients with knee arthritis, improvements in pain, stiffness and functional ability were seen with freeze-dried blueberries (Du 2019). In children with juvenile arthritis, blueberries improved outcomes when combined with standard treatment (Zhong 2015).
Compared to the risks from standard medications, blueberries are quite safe. While more research is needed, they could provide benefits for patients struggling with painful joints.
Blueberries and Blood Sugar
A recent review found that berries, including blueberries, can help control blood sugar and insulin after meals. They concluded that berries have an emerging role in protecting from the development of type 2 diabetes (Calvano 2019). A separate study looking at anthocyanins (found in blueberries and other foods) concluded that these compounds decrease inflammation related to obesity and could be an important component to helping control obesity-related health conditions, like diabetes (Lee 2017).
Conclusion
Blueberries are a simple, widely available food that appear to have benefits for a number of health conditions. While I don’t always like the hype and marketing strategies around superfoods, blueberries likely qualify.