Summer is when the best of the blueberry’s combo of tart and sweetness shines. It’s not just the taste that makes them special. The blue in the berries means they contain bioactive ingredients, which can help improve health and fend off the ill-effects of inflammation, which may reduce risk of heart disease and Metabolic Syndrome. There is as much science about the health benefits of blueberries as there are berries in the pints that you buy at the store.
Here is a quick review of what we know about the health benefits of blueberries.
Blueberries and Blood Pressure
A heaping cup of blueberries per day can lead to an improvement in blood vessel function and a decrease in systolic blood pressure in healthy people. Study subjects were given a drink containing 200g or blueberries (a hefty cup of blueberries), which they consumed daily for a month. The control group drank a blue beverage. Scientists measured each participants blood pressure and dilation of the brachial artery. This is a measure of measure of how the artery widens when blood flow increases, which is a biomarker of cardiovascular disease risk. They also looked at endothelial cells (a single cell layer that lines all blood vessels), which play a key role in blood clotting and regulating blood pressure.
In a second related study, the researchers compared the effects of a blueberry drink made from purified anthocyanins, the plant-based phytochemical responsible for the blue, red, pink and purple color in fruits and vegetables, such as berries and red grapes. They also compared this with control drinks containing comparable levels of fiber, mineral or vitamins found in blueberries.
The blueberry blood-pressure study results showed:
- The positive effects on blood vessel function were seen two hours after consumption of the blueberry drinks and were sustained for one month even after an overnight fast.
- Over the month, blood pressure was reduced by 5mmH, which is remarkably similar to what is seen in studies using blood pressure lowering medication.
- The drinks containing purified anthocyanins led to improvements in endothelial function.
- Neither the control drink, the control with fiber or the control with minerals and vitamins had a significant effect on artery dilation at two and six hours after consumption.
The researchers believe that eating whole blueberries is best for body, though this research proved it’s the anthocyanins in the fruit that gives it it’s heart healthy properties. “If the changes we saw in blood vessel function after eating blueberries every day could be sustained for a person’s whole life, it could reduce their risk of developing cardiovascular disease by up to 20%,” they said.
Blueberries and Metabolic Syndrome
A team of researchers worked to find whether eating about one cup (150mg) daily of blueberries had any effect on Metabolic Syndrome, a condition that affects one third of Westernized adults. This condition typically includes at least a trio the following risk factors: high blood pressure, high blood sugar, excess body fat around the waist, low levels of ‘good cholesterol’ and high levels of triglycerides.
“Having Metabolic syndrome significantly increases the risk of heart disease, stroke and diabetes and often statins and other medications are prescribed to help control this risk,” said lead researcher Aedin Cassidy, PhD. “It’s widely recognized that lifestyle changes, including making simple changes to food choices, can also help.”
The team investigated the effects of eating blueberries daily in 138 overweight and obese people, age 50 to 75, with Metabolic Syndrome. The six-month study was the longest trial of its kind. They looked at the benefits of eating one cup compared to half a cup of blueberries. The participants consumed the blueberries in freeze-dried form and a placebo group was given a purple-colored alternative made of artificial colors and flavorings.
Co-lead, Dr Peter Curtis, said: “We found that eating one cup of blueberries per day resulted in sustained improvements in vascular function and arterial stiffness – making enough of a difference to reduce the risk of cardiovascular disease by between 12 and 15 per cent. “The simple and attainable message is to consume one cup of blueberries daily to improve cardiovascular health.”
One cup is the key to success. The researchers were surprised to find that 75g or a half cup of blueberries per day did not help the participants of this study. “It is possible that higher daily intakes may be needed for heart health benefits in obese, at-risk populations, compared with the general population,” they said.
Blueberry Protein Bowls
This quick recipe is full of blueberry goodness, healthy protein from Greek yogurt and healthy fats from hemp and almonds. Recipe courtesy of U.S. Highbush Blueberry Council.
3 cups low-fat vanilla Greek yogurt
2 cups fresh blueberries
1⁄4 cup honey
4 teaspoons hemp seeds
1⁄4 cup sliced almonds, toasted
1⁄4 teaspoon ground cinnamon
- Divide yogurt between 4 bowls (¾ cup each). Top each bowl with ½ cup of blueberries.
- Drizzle each bowl with 1 tablespoon of honey and top with 1 teaspoon of hemp seeds, 1 tablespoon of almonds, and cinnamon.
This article is provided by the Institute for Natural Medicine, a non-profit 501(c)(3) organization, partnered with the American Association of Naturopathic Physicians. INM’s mission is to transform healthcare in America by increasing both public awareness of naturopathic medicine and access to naturopathic doctors for patients. INM believes that naturopathic medicine, with its unique principles and practices, has the potential to reverse the tide of chronic illness that overwhelms existing health care systems and to empower people to achieve and maintain their optimal lifelong health. INM strives to achieve this mission through the following initiatives:
- Education – Reveal the unique benefits and outcomes of naturopathic medicine
- Access – Connect patients to licensed naturopathic doctors
- Research – Expand quality research of this complex and comprehensive system of medicine
Ana Rodriguez-Mateos, Geoffrey Istas, Lisa Boschek, Rodrigo P Feliciano, Charlotte E Mills, Céline Boby, Sergio Gomez-Alonso, Dragan Milenkovic, Christian Heiss. Circulating anthocyanin metabolites mediate vascular benefits of blueberries: insights from randomized controlled trials, metabolomics, and nutrigenomics. The Journals of Gerontology: Series A, 2019; DOI: 10.1093/gerona/glz047
Peter J Curtis, Vera van der Velpen, Lindsey Berends, Amy Jennings, Martin Feelisch, A Margot Umpleby, Mark Evans, Bernadette O Fernandez, Mia S Meiss, Magdalena Minnion, John Potter, Anne-Marie Minihane, Colin D Kay, Eric B Rimm, Aedín Cassidy. Blueberries improve biomarkers of cardiometabolic function in participants with metabolic syndrome—results from a 6-month, double-blind, randomized controlled trial. The American Journal of Clinical Nutrition, 2019; 109 (6): 1535 DOI: 10.1093/ajcn/nqy380
Stewart is an award-winning editor, food and health journalist and best-selling author of Eating Between the Lines, the supermarket shopper's guide to the truth behind food labels (St. Martin's Press).