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Study under review: Efficacy and safety of turmeric and curcumin in lowering blood lipid levels in patients with cardiovascular risk factors: a meta-analysis of randomized controlled trials.
Introduction
Cardiovascular disease (CVD) is the number one cause of death in the U.S., but some of the risk factors for CVD are modifiable. One of the most well-known risk factors are serum lipid levels, in particular LDL cholesterol and triglycerides. Treatments that lower serum LDL[1] cholesterol have been shown to reduce risk for cardiovascular endpoints in at-risk populations. Additionally, preventive lifestyle interventions such as a healthy diet and exercise are highly effective and important to encourage, but even the most well meaning people can have problems with compliance. Researchers and healthcare practitioners alike are therefore interested in the potential properties of turmeric, and more specifically its active ingredient curcumin, for possible anti-inflammatory and lipid-lowering effects. Curcumin has long been touted[2] as having medicinal benefits, and the safety of curcumin, even at high doses[3], has been consistently demonstrated. Curcumin is a polyphenol shown in preclinical and clinical research to have anti-inflammatory[4] properties and its effects have been studied in people with numerous disease states[5][6][7]. In studies examining the effects of supplemental curcumin on participants with cancer, those receiving supplementation showed reduced levels of numerous proinflammatory biomarkers[2].
There are also several plausible mechanisms by which curcumin may affect cholesterol, which are summarized in Figure 1. However, the clinical evidence has been mixed. Though many of the studies are short term, some[8] show a significant effect of curcumin administration on total[9], LDL, or HDL cholesterol, although others do not[10]. The study under review attempted to gather all relevant clinical trials and pool the data to assess whether significant evidence exists showing a benefit for curcumin on cholesterol and triglyceride levels.

Curcumin has been shown to lower proinflammatory markers and even blood lipids in clinical and preclinical trials, but the total evidence showing curcumin for heart health is limited. In the study under review, the authors pooled data from qualifying studies of curcumin or turmeric on heart health in order to assess evidence for a therapeutic effect of curcumin on CVD risk.
Who and what was studied
What were the findings?
What does this study really tell us?
The big picture
Frequently asked question
What should I know?
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Interview: Gabrielle Fundaro PhD, CISSN
In this interview, we chat with researcher and weightlifter Gabrielle Fundaro about her health routine, the challenges of teaching complex biological concepts, the microbiome, and nutrition.
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Interview: Andrew Gelman, PhD
In this interview, we chat about important aspects of statistics and study design with one of the luminaries in the field.
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A progress report on supplements for osteoarthritis
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A look under the hood at carbohydrate intake during exercise
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Some TLC from ALC in depression
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Can whole eggs help make swole legs?
Getting enough protein is essential to help stimulate muscle growth. But the type of protein-containing food can also play a role.
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Zinc: an alternative path away from type 2 diabetes?
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