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Study under review: Association between berries intake and cardiovascular diseases risk factors: a systematic review with meta analysis and trial sequential analysis of randomized controlled trials
Introduction
Cardiovascular disease (CVD) is the leading cause of death worldwide. Attenuating risk factors is key to prevent disease development and progression. Blood lipids (total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides) are common intervention targets. An unhealthy diet can affect all of these, spurring researchers to investigate the health effects of various foods and dietary components.
Berries are a food that have long stood out for their high concentrations of bioactive compounds[1][2], such as anthocyanins, flavonols, tannins, and phenolic acids. These antioxidant, anti-inflammatory compounds are commonly referred to as polyphenols and have been investigated[3] for their potential to reduce CVD risk factors. The polyphenolic content of some foods can be seen in Figure 1. Anthocyanins, in particular, are concentrated in the skin of most berries and within the flesh of others. Berry color intensity is representative of anthocyanin concentration[4], which increases with ripeness and ranges between 2-4 g/kg. In addition to being a rich source of polyphenols, berries are low in calories, high in fiber, and quite delicious.
Two previous meta-analyses have indicated that berries improve multiple CVD risk factors, including blood lipids, blood pressure, and biomarkers of inflammation. One study[5] focused on Vaccinium berries, which includes cranberries, blueberries, bilberries, and whortleberries. The other study[6] investigated all berries consumed in whole, powder, or juice form. Since the former study focused only on certain berries, and the latter study did not include recently released trials, the study under review was conducted to provide an updated meta-analysis on the effects of berry consumption on CVD risk factors.
Berries are a low-calorie, high-fiber food renowned for their high concentrations of polyphenols. Numerous interventions have demonstrated beneficial effects of berry consumption on cardiovascular disease risk factors. The study under review is a meta-analysis of these studies.
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?
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