With goji berries dominating the health food aisle in supermarkets and acai berry smoothie bowls popping up at cafes everywhere around the country, it’s easy to forget the humble blueberry.
As with all fruits, blueberries are low in calories, high in dietary fibre and boast an impressive nutrient profile, providing the following per 1 cup serving:
Approximately 45% of the adult daily requirement for Vitamin K (28.6µg)
10% of the adult daily requirement for Manganese (0.5mg)
Blood Sugar Control
Blueberries (and all berries for that matter) are a lower carbohydrate choice when it comes to fruit, making them particularly suitable for diabetics or those with impaired blood sugar control.
1 cup of blueberries contains 20g total carbohydrates, compared with 30g found in a medium-sized banana and also provides 4g fibre, helping to slow the release of the naturally occurring fruit sugars into the blood stream.
Protection Against Heart Disease
Blueberries have been shown to improve several markers of heart disease.
An epidemiological study following 93 600 young healthy women over an 18 year period found that those with the highest intake of anthocyanins (the dominant antioxidant found in blueberries) had the lowest risk of heart attack (Cassidy et al 2013).
Consuming the equivalent of 2 cups of blueberries each day for 8 weeks lead to significant decreases in blood pressure (known as the ‘silent killer’ when it comes to heart disease) and oxidised LDL (the dangerous type of cholesterol in the blood) compared with controls (Basu et al 2010).
Cancer Prevention Although cancer is a complex disease and we are yet to understand the many causes and contributing factors to its onset and progression, one common mechanism involved is oxidative damage to our DNA.
Depending on the damage (the section of DNA involved, whether it can be repaired by normal cellular processes etc), oxidation of DNA can potentially result in a genetic mutation and the initiation of cancer (Poulsen et al 1998).
Fortunately, DNA is routinely damaged so our bodies have mechanisms in place to repair this damage. Dietary antioxidants combat oxidative stress and help to repair any resulting DNA damage. Anthocyanins belong to the flavonoid family of antioxidants and are the dominant type of antioxidants found in blueberries. They are also responsible for giving the fruit its purple colour (Wang et al 2014).
Anti-ageing Benefits Oxidative stress is also a contributing factor in the ageing process. Reactive oxidant species (ROS) are byproducts of many normal metabolic reactions in the body and are believed to be a major cause cellular ageing by triggering chain reactions that cause damage to our cells.
Dietary antioxidants, including the powerful anthocyanins in blueberries, terminate these chain reactions to prevent cellular damage and halt the ageing process (Peng et al 2014).
Animal studies have also shown supplementation with blueberries to prolong the lifespan (Peng et al 2012) and prevent the age-related decline in memory and other measures of cognitive function (Goyarzu et al 2004 and Coultrap et al 2008).
How to Enjoy Blueberries
- Add fresh or frozen blueberries to smoothies or yoghurt.
- Stir fresh or frozen blueberries through oats (or quinoa flakes for a gluten free alternative) that have been soaked in milk overnight to make homemade bircher muesli for a balanced summer breakfast. Alternatively, stir through cooked porridge for a winter breakfast when the weather cools down – perfect with a dash of vanilla!
- Make an apple and blueberry crumble for a winter dessert – simply place thinly sliced apple and a handful of blueberries in the base of a baking dish. Top with a mixture of oats (use quinoa for gluten free alternative), flaked almonds, coconut, cinnamon and a few dollops of butter (use coconut oil for a dairy free alternative). Bake until golden.
A Note on Frozen Berries
In February 2015 there was a frozen berry scare in Australia with several popular brands being pulled from the supermarket shelf following suspected contamination with Hepatitis A virus.
Although not all brands on the market were affected, this recent health scare simply highlights the importance of sourcing local fresh produce where available. The safest alternative would be to buy fresh blueberries in bulk when in season and freeze them yourself. Alternatively, purchase a different brand of frozen berries if you feel comfortable doing so.
Stay tuned for a tasty recipe featuring blueberries I’ll be sharing soon.
Basu et al (2010), ‘Blueberries Decrease Cardiovascular Risk Factors in Obese Men and Women with Metabolic Syndrome’, Journal of Nutrition, 140(9): 1582-1587.
Cassidy et al (2013), ‘High anthocyanin intake is associated with a reduced risk of myocardial infarction in young and middle-aged women’, Circulation, 127(2): 188-196.
Coultrap et al (2008), ‘Blueberry-enriched diet ameliorates age-related declines in NMDA receptor-dependent LTP’, Age, 30(4): 263-272.
Goyarzu et al (2004), ‘Blueberry supplemented diet: effects on object recognition memory and nuclear factor-kappa B levels in aged rats’, Nutritional Neuroscience, 7(2): 75-83.
Peng et al (2012), ‘Blueberry extract prolongs lifespan of Drosophila melanogaster’, Experimental Gerontology, 47(2): 170-178.
Peng et al (2014), ‘Biology of ageing and role of dietary antioxidants’, BioMed Research International.
Poulsen et al (1998), ‘Role of oxidative DNA damage in cancer initiation and promotion’, European Journal of Cancer Prevention, 7(1): 9-16.
Wang et al (2014), ‘Antioxidative Dietary Compounds Modulate Gene Expression Associated with Apoptosis, DNA Repair, Inhibition of Cell Proliferation and Migration’, International Journal of Molecular Biosciences, 15(9): 16226-16245.