Last updated on June 2, 2021.
You’ve probably heard that blueberries are good for your eyes. It is not just because of the shape and color of blueberries that resonate with the pupil of your eyes, but blueberries are considered to be one of the most nutritious foods in the world beyond their benefits for eye health. They are also labelled as a superfood, alongside other berries. Recent studies prove that moderate intake of blueberries is associated with a reduced risk of obesity, diabetes, heart disease and even death. More surprisingly, the antioxidant actions of blueberries can delay aging. Now, let’s explore the amazing health benefits of blueberries in further detail.
Blueberries are loaded with antioxidants
Blueberries are by far one of the most antioxidative foods in the world. There are numerous naturally occurring compounds contributing to their antioxidative power, and they are collectively known as phytochemicals, which give the distinctive bluish-purple colour of blueberries.
Recent research proves that antioxidants in blueberries can protect the body from oxidative stress. Oxidative stress is the accumulation of free radicals generated within your body and from external sources, such as processed food and air pollution. Oxidative stress can damage body cells, and cause DNA damage, cardiovascular disease and inflammation. Blueberries with high antioxidants can neutralize the free radicals to protect the DNA in cells, which in turn helps slow down aging and reduce the risk of cancer. Blueberries may be able to suppress tumor development and decrease inflammation to prevent the formation of cancer cells.
Blueberries are good for your eyes
Incorporating blueberries into your diet can improve vision. The retina is the component in the eyes that is responsible for vision by converting light energy to electrical signals. The signals stimulate the visual cortex of the brain and this is how an image is formed. The retina accumulates oxidative stress because of UV light exposure and other factors. Antioxidants in blueberries improve blood and oxygen flow to aid respiration and protect against the degeneration of the retina and different parts of the eyes.
Blueberries are good for your heart
Blueberries are packed with fiber, potassium, folate, vitamin C, vitamin B6 and phytochemicals that promote heart health. Fiber inhibits the oxidation of “bad” cholesterol in blood which is a predominant risk factor for cardiovascular disease. The potassium, calcium and magnesium in blueberries help lower blood pressure and reduce the risk of hypertension, while vitamin B6 and folate prevent the acceleration of homocysteine, a chemical that can damage blood vessels, in the body. Well-protected arteries reduce the risk of atherothrombosis and heart attack.
A study conducted in 2015 stated that the daily consumption of blueberries for a period of 6-week did not increase the level of blood pressure in patients with metabolic syndromes. This implies that the intake of blueberries can stabilize blood pressure.
Blueberries can improve cognitive function
In addition to the benefits for eyes and heart, a high intake of blueberries is associated with better brain function. Research shows that blueberries can slow down the decline in cognitive functions, including memory loss and emotional instability. Blueberries also reduce the oxidative stress in the nerve cells to maintain the function of neurons to transmit nerve impulse.
A 12-week study showed that daily consumption of blueberry juice improves the memory of older adults as indicated by word list recall and paired-associate learning. The study even suggested that there were improvements in depressive symptoms and blood glucose levels in participants.
Blueberries can help regulate blood sugar level
Type II Diabetes has become more prevalent around the world, especially in developed countries. Patients with Type II Diabetes cannot effectively utilize or convert blood glucose due to cellular insulin resistance. Insulin is an anabolic hormone responsible for catalyzing glycogenesis and lipogenesis, thus, reducing blood glucose level. So diabetic patients have higher blood glucose levels than normal people. Too much sugar circulating in the bloodstream can potentially cause health problems, such as neuropathy (nerve dysfunction), cardiovascular diseases, nephropathy (kidney disease), eyes and lower limbs damage and immunodeficiency to diabetic patients.
Even though blueberries contain plenty of sugar — 15g of sugar per cup of blueberries, they do not trigger the rise of blood glucose level significantly as their bioactive content increases insulin sensitivity, thus regulating blood sugar level of diabetic patients. Therefore, blueberries are considered safe for people with diabetes.
Besides, eating blueberries after a high-carb meal can manage blood sugar level and prevent blood sugar spikes.
Are blueberries better fresh or frozen?
The short answer is fresh. Even though the evidence is not conclusive at this point, it is suggested that freezing may potentially hinder the bioavailability of healthy nutrients in blueberries. One study even suggested that there is a reduction of 59% of anthocyanin, a major component of antioxidants in blueberries, after 6 months of storage.
Are blueberries safe for everyone?
People who are taking blood-thinners such as warfarin should be aware of the amount of blueberries and Vitamin K intake in general. Vitamin K present in blueberries is responsible for blood clotting and might potentially counteract the blood-thinning property of the drugs.
Also, blueberries and some other fruits contain salicylates. People who are allergic to this compound may experience skin rash and swelling after eating blueberries. Consult a doctor if in doubt.
Should you peel off the skin of blueberries?
A big no! Most nutrients concentrate on the skin of blueberries, where fiber, vitamins and minerals can all be found.