Examine publishes rigorous, unbiased analysis of the latest and most important nutrition and supplementation studies each month, available to all Examine Members. Click here to learn more or log in.
Study under review: Blueberries improve biomarkers of cardiometabolic function in participants with metabolic syndrome-results from a 6-month, double-blind, randomized controlled trial.
Introduction
Metabolic syndrome[1] refers to a cluster of issues that arise from a disordered metabolism, including impaired glucose tolerance, elevated triglycerides and LDL-cholesterol. Metabolic syndrome increases the risk of several chronic diseases, specifically type 2 diabetes[2] (T2DM) and cardiovascular disease[3] (CVD). As of 2012, the prevalence of metabolic syndrome in the U.S. was about 35% in adults[4] and about 5-7% in young adults[5]. Accordingly, interventions that can address metabolic syndrome are warranted.
Metabolic syndrome can be addressed through pharmacological interventions and/or lifestyle modification. Pharmacological options often utilize glucose-lowering agents such as metformin or GLP-1 receptor agonists, and/or lipid lowering agents such as statins, fenofibrates, or thiazolidinediones. Lifestyle interventions, on the other hand, rely heavily on exercise and caloric restriction[6]. They have been shown, time and again, to provide therapeutic benefits and improve many of the aspects of metabolic disease synergistically. In addition to pharmacological interventions and lifestyle modifications, specific nutritional interventions, such as nutraceuticals, may also be a useful tool in the management of metabolic syndrome. Blueberries are one such intervention that shows promise.
Blueberries contain many bioactive compounds. Specifically, they contain a group of compounds called flavonoids. Anthocyanins are a group of flavonoids that are found in high concentration in blueberries. In observational studies, higher intakes of anthocyanins are associated with a lower risk[7] of diabetes and a previous randomized controlled trial found that 50 grams of blueberries per day reduced blood pressure[8] and provided antioxidant benefits to people with metabolic syndrome. The present study is a randomized controlled trial examining the effect of six months of dietarily achievable blueberry intake on insulin resistance and cardiometabolic function in people with metabolic syndrome.
Metabolic syndrome occurs in roughly one-third of all adults in the U.S. Blueberries contain bioactive compounds, specifically a family of compounds called anthocyanins that may provide benefits for people with metabolic syndrome. The present study is a randomized controlled trial examining the effect of six months of dietary blueberry intake on insulin resistance and cardiometabolic function in metabolic syndrome.
Who and what was studied?
What were the findings?
What does this study really tell us?
The big picture
Frequently Asked Questions
What should I know?
Other Articles in Issue #58 (August 2019)
-
Eating early in the day keeps glucose spikes at bay
In addition to helping with glycemic control, early time-restricted feeding may affect the expression of certain genes related to circadian rhythms and longevity, too.
-
Causally or corollary? An innovatively random approach to the TMAO question
Some research has supported the idea that trimethylamine N-oxide (TMAO, a metabolite of compounds found in animal products) is as scary as it sounds. But that research was mostly observational. This study investigated whether TMAO's link to metabolic disease is causal.
-
Under pressure: reducing salt intake to lower blood pressure
Does reducing salt intake actually reduce blood pressure? If so, by how much? This meta-analysis aimed to answer these questions.
-
Your brain on ketones: Does a ketogenic diet affect cognition, sleep, and mood?
Ketogenic diets affect nerves; that's why they're an effective treatment for some seizure disorders. But how these diets affect mood and cognition is less clear.
-
Interview: Lisa Lewis, EdD, CADC-II
In this interview with sports psychologist Lisa Lewis, we chat about some key takeaways from the field of sports psychology, behavioral addiction in sports, and more.
-
Mini: WHO guidelines for reducing the risk of cognitive decline and dementia
There's no cure for dementia, but there are some clear modifiable risk factors. Here, we summarize the first-ever World Health Organization guidelines for reducing the risk of cognitive decline and dementia.
-
Low-calorie sweeteners: are they all created equal?
This clinical trial explored how four low-calories sweeteners affect bodyweight, body composition, and more.