Randomized Double-Blind Controlled Trial of Freeze-Dried Strawberry Powder Supplementation in Adults with Overweight or Obesity and Elevated Cholesterol

Abstract

Objective Recommended dietary patterns improve cardiovascular disease (CVD) risk factors such as blood pressure and LDL-C, as well as emerging markers that confer residual risk. Strawberry consumption has been shown to improve CVD risk factors, but further research is needed to better understand these effects using a dose-response model that evaluates a standard serving and a higher (but still achievable) dose. Methods A randomized, placebo-controlled, double-blinded crossover trial was conducted in middle-aged adults with overweight or obesity (n = 40; mean BMI = 29.4 ± 0.2 kg/m2; mean age = 50 ± 1.0 years) and moderately elevated LDL-C (mean LDL-C: 140 ± 3 mg/dL) to investigate the effect of two doses of strawberry supplementation on LDL-C and other CVD risk factors. Study interventions were: 0 g/d (control), 13 g/d (low-dose), and 40 g/d (high-dose) of freeze-dried strawberry powder (4-week supplementation periods separated by a 2-week compliance break). Results There was a significant main effect of treatment for the primary outcome of LDL-C, with a 4.9% reduction following the low-dose strawberry supplement compared to the high-dose (P = 0.01), but not compared to the control. There was also a significant effect on total cholesterol (TC), with a 2.8% and 2.4% reduction following the low-dose compared to the control and high-dose, respectively (P ≤ 0.05 in post-hoc analyses). There was a near significant effect for direct LDL-C (P = 0.07). There were no significant treatment effects for other atherogenic lipoprotein characteristics, indices of vascular function, measures of inflammation, or HDL efflux. Conclusion Low-dose supplementation with freeze-dried strawberry powder, equivalent to ∼1 serving/day of fresh strawberries, improved cholesterol in adults with overweight or obesity, compared to both the high-dose (∼3 servings/day of fresh strawberries) and control, but did not alter other markers of CVD. Supplemental data for this article is available online at