This so-called ‘superfood’ stands up to the science.
By Dr Roger Henderson and words by Annie Hayes
As one of the most nutrient-dense berry varieties in the world, the health benefits of blueberries are many and varied. Deliciously sweet, readily-available and low in calories, blueberries are favoured among health-conscious shoppers who blitz them into smoothies, stir them into breakfast favourites such as porridge or yoghurt, and even sprinkle them into salads.
While blueberries are frequently touted as a ‘superfood’ – a marketing term for foods purported to have higher-than-average nutrient density – the various benefits of blueberries stand up to science. We run through the proven health benefits of blueberries with nutritionist Jenna Hope:
11 proven health benefits of blueberries
Blueberries come from a blueberry bush, which is a flowering shrub that is closely related to those that grow cranberries, bilberries, lingonberries, and huckleberries. Many of the benefits of blueberries are due to the various plant compounds found in the berry, including polyphenols.
‘Polyphenols are potent antioxidants which help to counterbalance free radicals in the body,’ Hope says. ‘Blueberries are rich in anthocyanins, a type of polyphenol that has been shown to support heart health.’
They’re also packed with vitamins – including vitamin C, ‘a vital component to supporting a healthy immune function,’ Hope adds – and are a source of fibre, ‘which helps to support a healthy gut bacteria’.
‘Research suggests that just one-third of a cup per day can help to reduce disease risk.’
Blueberries are really versatile, so it’s easy to obtain the health benefits. Research suggests that just one-third of a cup per day can help to reduce disease risk, says Hope, with one serving equivalent to 80g of blueberries.
‘You can try adding blueberries to porridge, salads, smoothies, blending them up with yoghurt and freezing them for a healthier snack,’ she says. ‘You can also try combining them with chia seeds to make a blueberry jam.’
These are just a few of the reasons to consider adding the healthful blue orbs to your diet. Read on for 11 evidence-backed benefits of blueberries:
- Extremely nutrient-rich
Blueberries have an impressive nutritional profile. They’re a good source of several vitamins and minerals, with a 150g portion containing around a quarter of your daily vitamin C and manganese requirements, and more than a third of your vitamin K1 needs. Blueberries also contain small amounts of vitamin E, vitamin B6 and copper.
- Good for your gut
Blueberries are also rich in gut-healthy fibre – they can alleviate and protect against intestinal inflammations such as ulcerative colitis, according to research from the Lund University Faculty of Engineering in Sweden, which found that the protective effect is even better if the blueberries are eaten with probiotics. ‘Recommendations are 30g of fibre per day,’ says Hope. ‘One serving of 80g blueberries contains around 1.5g.’
- Contain potent antioxidants
One of the main benefits of blueberries can be attributed to their rich antioxidant content. Antioxidants protect your body from free radicals, waste substances produced by cells in the body as it reacts to environmental stressors and processes food, which have been linked to diseases such as heart disease, cancer, arthritis and stroke.
One of the main benefits of blueberries can be attributed to their rich antioxidant content.
Blueberries have one of the highest antioxidant levels of all fruits and vegetables. The main antioxidants in blueberries are flavonoids, a type of polyphenol. Freezing the blueberries improves the availability of the antioxidants, according to South Dakota State University.
- Reduce DNA damage
The oxidative stress caused by free radicals also damages your DNA, contributing to the ageing process as well as playing a role in the development of diseases. Being high in antioxidants, blueberries can help to prevent some of the free radicals from damaging your DNA. Drinking one litre of blueberry juice a day for four weeks reduced oxidative DNA damage caused by free radicals by 20 per cent in participants, a study published in the journal Carcinogenesis found.
- Lower heart disease risk
Eating 150g of blueberries every day reduces the risk of cardiovascular disease by up to 15 per cent, according to a six-month study led by the University of East Anglia. Researchers reported ‘sustained improvements in vascular function and arterial stiffness’ in participants, all of whom had metabolic syndrome – a condition that significantly increases the risk of heart disease, stroke and diabetes. ‘This may be because blueberries are high in naturally occurring compounds called anthocyanins, which are the flavonoids responsible for the red and blue colour in fruits,’ said lead researcher Professor Aedin Cassidy.
- Protect brain function
Phytochemical-rich foods such as blueberries are effective at reversing age-related deficits in both short-term and long-term memory, according to The Peninsula College of Medicine and Dentistry. Although the precise mechanisms remain unknown, the flavonoids in the blueberries have been shown to activate signalling proteins via a specific pathway in the hippocampus – the part of the brain that controls learning and memory.
When a group of volunteers in their 70s with early memory decline drank between two and two-and-a-half cups of commercially available blueberry juice every day for two months in a study by the American Chemical Society, they showed ‘significant improvement on learning and memory tests’ compared to the control group. ‘These preliminary memory findings are encouraging and suggest that consistent supplementation with blueberries may offer an approach to forestall or mitigate neurodegeneration,’ a report stated.
- Boost concentration
Blueberries can significantly improve concentration and memory, according to a study from Reading University. Participants were asked to drink a smoothie containing 200g blueberries in the morning before sitting attention tests. By the afternoon, the smoothie drinkers’ brainpower was 15 to 20 per cent higher than the control group. The flavonoids within blueberries are thought to increase blood flow to the brain and interact with signal pathways that are crucial to cell survival and growth.
- Control blood sugar
While blueberries contain sugar – around 15g per 150g serve – lab studies suggest that the anthocyanins in blueberries can help to control blood sugar levels by improving insulin sensitivity. Where insulin resistance increases the risk of metabolic syndrome and type 2 diabetes, effective insulin sensitivity lowers the risk. Blueberries have also been found to block certain digestive enzymes after a carb-heavy meal, helping to reduce spikes in blood sugar.
- Protect cholesterol
In the same way the antioxidants in blueberries protect your cells and DNA, they also help to prevent LDL (bad) cholesterol in the body from becoming oxidised. This is important, since oxidised LDL cholesterol can lead to heart disease. Over the course of an eight week study by Oklahoma State University, consuming 50g of blueberries every day lowered LDL oxidation by 27 per cent.
- Lower blood pressure
Eating blueberries has been linked to lower blood pressure in several studies, resulting in a protective effect for the heart – high blood pressure is a major risk factor for heart disease. In the same Oklahoma State University study above, researchers measured a four to six per cent reduction in participants’ blood pressure over the eight-week course.
- May aid muscle recovery
While more research is needed, early studies suggest that blueberries may help you recover quicker after a tough workout. A small study published in the Journal of the International Society of Sports Nutrition found that drinking a blueberry smoothie both pre- and post-workout accelerates the recovery period.