Out of countless nutrient-dense “superfoods”, blueberries are probably one of the most popular. They are well-known for their antioxidant content and taste so good that eating them is a joy, not a chore. Picking blueberries is one of my favorite activities in summer, and I had the opportunity to pick some at a local farm just last Saturday.
As I have been enjoying the fresh blueberries this week, I thought I would look deeper into their health benefits. We all know that blueberries are a healthy food, but exactly how are blueberries good for you?
It turns out that the health benefits of blueberries come mainly from their anthocyanin content. Anthocyanins are a group of pigments that give color to ripe fruit and also act as antioxidants. Blueberries have a greater anthocyanin content than most other fruits, and they also contain several other antioxidants.
There is growing interest in the health benefits of blueberries, and research has found that the consumption of blueberries and anthocyanins is associated with disease risk reduction. In a 2019 review in Advances in Nutrition, researchers Kaly et. al lay out the discoveries that science has made about the benefits of blueberries. Keep reading to find out about the four major ways blueberries can benefit your health. You may be surprised by the power of this little fruit.
Protecting heart health and managing weight
The first major benefit of blueberries is in protecting cardiovascular health. Studies have found that anthocyanin and blueberry intake are associated with a reduced risk of coronary artery disease, heart attack, and stroke. Higher anthocyanin intake has also been associated with a reduced risk of high blood pressure and improved vascular stiffness, which are measures of cardiovascular health.
Blueberries are not only good for your heart, but also can help you lose and manage your weight. Blueberry and anthocyanin intake have been associated with reduced body weight and fat mass in several studies. In one study that compared the effects of 16 different fruits, the highest blueberry intake was associated with the least weight gain in 133,000 men and women followed for up to 24 years. Since excess weight is a major risk factor for cardiovascular disease, this is one more way in which blueberries can help protect your heart.
The benefits of blueberries for heart health have also been shown in clinical studies. Blueberry intake has been found to improve markers such as cholesterol, triglycerides, arterial stiffness, and blood pressure. These benefits come from the antioxidant and anti-inflammatory effects of blueberries and regulation of plasma lipid and metabolism.
Since heart disease is the leading cause of death in the United States, protecting our heart health should be a top priority. Having some blueberries is one simple and delicious step that you can take toward that goal.
Preventing type 2 diabetes and prediabetes
Type 2 diabetes is another significant public health crisis, affecting about 100 million adults in the United States. As it turns out, blueberries can also reduce risk in this area. In three studies analyzing subjects’ intake of several fruits over time, blueberries had the most signifcant association with reduced risk of diabetes. One meta-analysis found that a higher rate of anthocyanin and berry consumption was associated with a reduced risk of type 2 diabetes. And in one observational study in women, higher intake of anthocyanins was associated with improvements in imsulin resistance and a decrease in inflammation.
The benefits of blueberries for diabetics have also been validated by clinical trials. In one study, obese, insulin-resistant adults experienced improved insulin sensitivity after eating blueberries for 6 weeks. In another study, overweight young adults who replaced 50 g carbohydrate with 50 g blueberries saw improvements in body weight, insulin, cholesterol, and other factors. Anthocyanin extract has also been found to improve insulin sensitivity, plasma lipid profiles, and markers of oxidative stress.
It is thought that blueberries improve outcomes for diabetes because they support the growth of beneficial gut bacteria which help to reduce inflammation. The weight-loss benefits of blueberries also help in lowering the risk for type 2 diabetes.
It is amazing enough that blueberries may lower the risk of heart disease and diabetes, but did you know they are also good for your brain?
One way blueberries may support brain health is by preventing cognitive decline in older adults. In one population study, high intake of anthocyanins and berries was associated with lower risk of Parkinson disease. In another study of 16,000 women, greater intake of blueberries and strawberries was associated with a delay in cognitive decline of about 2.5 years. Blueberry intake may be associated with a lower risk of dementia because the anthocyanins protect against heart disease and type 2 diabetes, which increase the risk of dementia.
The cognitive benefits of blueberries have been supported by clinical studies of both children and adults. Several clinical studies have found that after several weeks of blueberry intake, older adults show improvements in areas such as task switching and memory performance. The benefits were greater in the participants with mild cognitive impairment as compared to unimpaired participants. In another study, greater brain activity was detected using magnetic resonance imaging in older adults after 12 weeks of blueberry consumption.
In addition to the studies in older adults, a few studies have investigated the effects of a blueberry supplement on children’s cognitive functioning. In these studies, children who were given a blueberry supplement before a cognitive task performed better than those who were given a placebo. Amazingly, these benefits were seen just a few hours after supplementing with 15-30 g of blueberry powder.
Blueberries are so good for your brain because their antioxidants fight inflammation and oxidative stress in the brain. This improves neurogenesis and neuroplasticity, which allows you to think, learn, and remember more effectively. If you want to perform at your best cognitively and stay sharp throughout life, you will certainly want to make blueberries a part of your diet.
Vision and eye health
There has been relatively little research on the effects of blueberries on eye health, but there is some interest in this area because of the antioxidants in blueberries. The retina, the layer of tissue at the back of the eyeball that converts light into neural signals, is an area of significant oxidative stress and inflammation. It is thought that the anthocyanins found in blueberries may mitigate oxidative stress and inflammation in the retina.
Studies have shown that blueberries may help manage certain eye diseases. In one population study of women age 45 and over, there was a significant association between blueberry intake and reduced age-related macular degeneration, but no association with cataracts. A few clinical studies have also found improvements in glaucoma patients following prolonged daily anthocyanin intake. And in a study of diabetic retinopathy patients, intake of 510 g of anthocyanins for 12 months was associated with improved contrast sensitivity (the ability to distinguish an object from its background).
Blueberries may even have benefits for myopia (near-sightedness). In studies of myopic subjects, anthocyanin intake has been associated with improvements in visual accommodation (the adjustment of the lens of the eye to focus objects), dark adaptation, and ocular fatigue. So, if you did not have enough reasons to start eating blueberries, you can add preserving your eyesight to the list.
Blueberries: good for you in so many ways
Blueberries have an excellent reputation as a healthy food, and it is very well deserved. Personally, I was amazed to learn how blueberries can positively impact so many different systems in the body. It is fascinating that science is still discovering the benefits of natural, seemingly simple foods such as blueberries.
If you don’t already eat blueberries on a regular basis, it would be a great idea to start including them in your diet. Considering their delicious taste and the wide range of potential health benefits, there truly is no reason not to eat them.
Because certain methods of processing can decrease the anthocyanin content of blueberries, it is best to eat them fresh or frozen for the greatest benefit. Put them in smoothies, on cereal or oatmeal, in muffins, or have them alone as a quick snack.
Did you know about all the ways blueberries are good for you? What is your favorite way to enjoy blueberries? Share your thoughts below!
Wilhelmina Kalt, Aedin Cassidy, Luke R Howard, Robert Krikorian, April J Stull, Francois Tremblay, Raul Zamora-Ros, Recent Research on the Health Benefits of Blueberries and Their Anthocyanins, Advances in Nutrition, Volume 11, Issue 2, March 2020, Pages 224–236, https://doi.org/10.1093/advances/nmz065