Blueberries are a powerful fruit filled with vitamins, minerals and antioxidants. The health benefits of blueberries are plentiful and nourish the body in a variety of different ways. Read on to find out how these berries can be beneficial to your health!
5 Important Health Benefits of Blueberries
1. Offer Cognitive Support
New areas of research have shown that blueberries support our cognitive system. In one study, daily drinking of wild blueberry juice (2 1/2 cups/day) improved the memory of older adults with age-related memory problems, and may even post-pone or slow down the onset of other cognitive problems often associated with aging (1).
Why do blueberries offer such strong cognitive support? It mainly has to do with the antioxidants offered in blueberries, namely, the flavonoids. These antioxidants may activate neuronal receptors, signalling proteins and gene expression in the hippocampus (2). Particularly, the flavonol monomers (-)-epicatechin and catechin and anthocyanins mediate improvements in spatial memory in aged animals when fed a diet supplemented with blueberries. Protecting nerve cells from oxygen damage is yet another way the antioxidants in these berries support our nervous system. Keeping our nervous system running smoothly is an important factor we must take into consideration when it comes to our overall health – the nervous system is what keeps all of our organs, senses, and mind in touch with our body.
2. Reduce Body Fat
It might come as a surprise to say that blueberries are effective in reducing our total body fat and body fat storage. Preclinical studies have demonstrated that supplementing obese, insulin-resistant men and women’s diets with whole blueberries results in a reduction in glucose concentrations over time (3). Other studies have shown that rats who ate a blueberry-rich diet on top of an otherwise unhealthy diet, lost abdominal fat (the type of fat most commonly linked to heart disease and diabetes), and had lower cholesterol and improved glucose control (4).
The reason this occurs can likely be attributed to the blueberry’s rich source of phytochemicals such as anthocyanins that may change how the body stores and processes glucose for energy. In fact, these researchers went further to prove just that. Seymour and colleagues (5) found that anthocyanins can alter peroxisome proliferator-activated receptor (PPAR) activity, which affect energy substrate metabolism. Blueberry intake reduced abdominal fat, increased adipose and skeletal muscle PPAR activity and modified PPAR transcripts that play a role in fat oxidation and glucose uptake/oxidation. Thus, our bodies become more efficient at metabolizing fat when we consume diets rich in antioxidants, especially with the consumption of fruits that are high in antioxidants such as blueberries.
3. Anti-Cancer Benefits
Many types of cancers have been studied in respect to blueberry intake. These include, breast, colon, and esophageal cancer, and cancers of the small intestine. Again, the main reason blueberries are effective in preventing cancer is mainly due to their antioxidants. Polyphenols in blueberries were separated into phenolic acids (tannins, flavonols, and anthocyanins), and were added to cell culture mediums containing two colon cancer cell lines to test for anti-proliferation activities and whether they could induce apoptosis (cell death). The greatest anti-proliferation effects were found with the anthocyanins, with up to 50% inhibition of growth of the two cancer cell lines. In addition, the anthocyanins resulted in 2-7 times increases in DNA fragmentation (indicating apoptosis, or in other words, cell death of the cancer). These findings suggest that daily blueberry intake may reduce colon cancer risk (6).
The antioxidants in blueberries are mostly mediated through their ability to reduce, counteract and repair oxidative damage. They have also been found to regulate carcinogen and xenobiotic metabolizing enzymes, transcription and growth factors, inflammatory cytokines, and subcellular signaling pathways of cancer cell apoptosis, proliferation and tumour angiogenesis (7). The antioxidants in blueberries may also sensitize tumour cells to chemotherapy drugs by inhibiting treatment resistant pathways (cancer cells that become resistant to chemotherapy).
4. Rich Source of Antioxidants
All berries are rich in antioxidants, however, blueberries rank on the higher end. Antioxidants help fight illness and disease like cancer and heart-related issues. In fact, every point in this article revolves around specific antioxidants in this powerful little berry. Antioxidants help prevent and repair stress that comes from oxidation in the body. Free radicals develop when cells become damaged during oxidation, and can start a chain reaction that can harm more cells and create disease such as cancer, heart disease, Alzheimer’s and Parkinson’s disease. Blueberries contain anthocyanins (malvidins, delpinidins, pelargonidins, cyaniding, peonidins), hydroxycinnamic acids (caffein acids, ferulic acids, coumaric acids), hydroxybenzoic acids (coumaric acids), hydroxybenzoic acids (gallic acids, procatchuic acids), flavonols (kaemphferol, quercetin, myricetin) and other phenol-related phytonutrients such as pterostilbene and resveratrol.
5. Cardiovascular Benefits
The effects of antioxidants in blueberries is especially noteworthy in the cardiovascular system. Among all fruits, berries (particularly, blueberries used in this study), and their high polyphenol content have been shown to protect our cardiovascular system. Blueberry supplementation on metabolic syndrome, lipid peroxidation and inflammation was observed in obese men and women (8). They ate 350 grams of fresh blueberries (or just water for controls) daily for eight weeks. The group that consumed blueberries after the eight week period had reduced LDL cholesterol as well as major decreases in systolic and diastolic blood pressures compared to controls.
Blueberry intake has also been shown to protect blood components from oxygen damage (which often leads to blood clotting over time) (9). Blueberry-enriched diets also protect the myocardium (the muscular middle layer of the wall of the heart, which stimulates the heart to contract and pump blood from the ventricles) from induced ischemic damage (9). Consuming adequate amounts of blueberries (2 or more cups a day), can help improve the overall antioxidant capacity of the blood, contributing to the above effects.
Underlying mechanisms for these beneficial effects may include the “upregulation of endothelial nitric oxide synthase, decreased activities of carbohydrate digestive enzymes, decreased oxidative stress, and inhibition of inflammatory gene expression and foam cell formation.” (10)
So what are you waiting for?! Go eat some blueberries! Make sure they are organic, however…conventional blueberries are one of the fruits that are sprayed with many pesticides – this will basically make the effects of the blueberries pointless.
Sources:
(1) Krikorian, R., Shidler, M., Nash, T., Kalt, W., Vinqvist-Tymchuk, M., Shukitt-Hale, B., & Joseph, J. (2010). Blueberry supplementation improves memory in older adults. Journal of Agricultural and Food Chemistry, 58, 3996-4000.
(2) Rendeiro, C. (2011). The effects of flavonoids and flavonoid-rich blueberries on memory and the mechanisms by which these effects are mediated. University of Reading.
(3) Stull, A., Cash, K., Johnson, W., Champagne, C., & Cefalu, W. (2010). Bioactives in blueberries improve insulin sensitivity in obese, insulin-resistant men and women. American Society for Nutrition, 140, 1764-1768.
(4) University of Michigan News Rooms (2009). Blueberries make their mark on cardiovascular and diabetes risks, U-M animal study finds. University of Michigan Health System.
(5) Seymour, M., Tanone, I., Urcuyo-Llanes, D., Lewis, S., Kirakosyan, A., Kondoleon, M., Kaufman, P., & Bolling, S. (2011). Blueberry intake alters skeletal muscle and adipose tissue peroxisome proliferator-activated receptor activity and reduces insulin resistance in obese rats. Journal of Medicinal Food, 14, 1511-1518.
(6) Yi, W., Fischer, J., Krewer, G., & Akoh, C. (2005). Phenolic compounds from blueberries can inhibit colon cancer cell proliferation and induce apoptosis. Journal of Agricultural and Food Chemistry, 53, 7320-7329.
(7) Seeram, N., (2008). Berry fruits for cancer prevention: current status and future prospects. Journal of Agricultural and Food Chemistry, 56, 630-635.
(8) Basu, A., Du, M., Leyva, M., Sanchez, K., Betts, N., Wu, M., Aston, C., Lyons, T. (2010). Blueberries decrease cardiovascular risk factors in obese men and women with metabolic syndrome. American Society for Nutrition, 140, 1582-1587.
(9) Ahmet, I., Spangler, E., Shukitt-Hale, B., Juhaszova, M., Sollott, S., Joseph, J., Ingram, D., & Talan, M. (2009). Blueberry-enriched diet protects rat heart from ischemic damage. PLoS ONE 4(6):e5954. doi:10.1371/journal.pone.0005954.
(10) Basu, A., Rhone, M., Lyons, T. (2010). Berries: emerging impact on cardiovascular health. Nutrition Reviews, 68, 168-177.
