Mini but Mighty!
Blueberries might be mini, but they’re definitely mighty! These berries are rich in phytochemicals such as anthocyanin, fibre as well as vitamins and minerals such as vitamin K, vitamin C, folate and manganese.
Let’s not forget anthocyanins…
The main antioxidant compound found in blueberries are known as anthocyanins. This is what gives blueberries their deep blue colour. Anthocyanins belong to a large family of polyphenols called flavonoids. Anthocyanins are the main reason behind why blueberries are receiving so much attention for their health benefits.
What benefits could blueberries have?
Blueberries have been investigated for many reasons. It is thought that their habitual consumption over time could be linked to reduced rates of cardiovascular disease and ageing. For example, a 2010 review by Basu et al. examined the effect of blueberries and strawberries on cardiovascular health outcomes. Based off the epidemiological and clinical studies they examined, they concluded that habitual intake of berries was linked to improvements into risk factors for cardiovascular disease, such as high concentrations of LDL-cholesterol, high blood lipids as well as improvements in total plasma antioxidant capacity. All of these factors contribute to a reduction in risk of developing cardiovascular disease. This highlights the fact that including blueberries daily can have heart-healthy benefits.
What about blueberries and the brain?
Another key area of interest is into the effect of habitual consumption of blueberries on the brain, specifically on memory and cognitive decline. It is now generally accepted that blueberries may have a potential nootropic effect.
The effect of consumption on cognitive decline in older adults has been studied. A 2010 study in older adults examined the effect of daily consumption of blueberry juice for 12 weeks (1). They found that was associated with improvements in verbal learning and memory. They also found that improvements occurred in blood glucose and insulin levels.
Findings from the Nurse’s Healthy Study also support the neurocognitive benefits of regular blueberry consumption (2). Greater intakes of blueberries were associated with slower rates of cognitive decline. Based off the findings of this cohort, it is thought that berry consumption could delay cognitive aging by up to 2.5 years.
A ten-year follow up study also found that higher flavonoid intakes was associated with significantly better cognitive performance at baseline and with a better evolution of the performance over time (3).
What makes blueberries so special?
We’re not yet entirely sure what gives blueberries their neuroprotective benefits. There are however a few guesses as to what makes them so special.
A key factor is thought to be their antioxidant content. As discussed previously, blueberries contain high amounts of antioxidants known as anthocyanins which gives them anti-oxidative effects. Antioxidants have the ability to protect cells, such as brain cells, from harm caused by free radicals and oxidative stress within the body. Oxidative stress is thought to play a key role in the development of neurodegenerative diseases.
Blueberries also appear to have anti-inflammatory effects. Excessive inflammation is also thought to play a role in neurocognitive decline. Blueberry intake has been shown to lead to decreases in key factors involved in inflammatory pathways in the body, such as the nuclear-factor kappa B transcription factor and tumour-necrosis factor A.
What’s the take home?
Nutritional science is complicated and diseases such as diseases involving neurocognitive decline are also complicated. While more research is needed into this area, blueberries could be an important addition to our diet, and especially the elderly. They’re a great fruit to include regularly due to their high antioxidant, vitamin and fibre content.
References
1. Krikorian R, Shidler MD, Nash TA, Kalt W, Vinqvist-Tymchuk MR, Shukitt-Hale B, et al. Blueberry supplementation improves memory in older adults. J Agric Food Chem. 2010;
2. Devore EE, Kang JH, Breteler MMB, Grodstein F. Dietary intakes of berries and flavonoids in relation to cognitive decline. Ann Neurol. 2012;
3. Letenneur L, Proust-Lima C, Le Gouge A, Dartigues JF, Barberger-Gateau P. Flavonoid intake and cognitive decline over a 10-year period. Am J Epidemiol. 2007;