Maximizing the health effects of strawberry anthocyanins: understanding the influence of the consumption timing variable

Abstract

Strawberries, rich in anthocyanins, attenuate meal-induced postprandial increases in inflammation and oxidative stress as well as improved post-meal insulin responses. While previous studies have focused on the health effects of strawberry consumption ingested with a meal, this study aimed to determine if consuming strawberries at alternative times near a meal would influence meal-induced oxidative–immuno–metabolic outcomes. Fourteen overweight healthy adults participated in a 3-arm, single-blinded, crossover clinical trial delivering a strawberry drink at 1 of 3 different time points: 2 hours before a standard meal, with the meal, or 2 hours after the meal. Control drinks were provided at the alternative time points so that 3 drinks were consumed at each study visit. Blood samples were collected over 10 h. Comparisons of plasma analytes were between strawberry “timing” groups and secondarily with a demographically matched reference group that ingested only control drinks (no strawberry). The study results showed significant reduction in postprandial glucose when strawberry was consumed before the meal compared to having the strawberry drink with the meal, p < 0.05. Compared to the reference group, consuming strawberries before and after the meal attenuated postprandial glucose without additional insulin, suggesting improved insulin sensitivity. Interleukin-6 was significantly lower after consuming the strawberry drink before the meal (p = 0.048) compared to the reference group. This study provides data suggesting that strawberries have a role in glycemic control and attenuating the pro-inflammatory effect of a modern diet. There may be particular advantages when strawberries are consumed before a meal.