Research suggests that anthocyanins—the most prominent flavonoid in the diet—and the consumption of anthocyanin-rich foods such as strawberries may play an important role in helping reduce the risk of cardiovascular disease. To evaluate the effects of specific amounts of strawberries on cardiovascular risk factors, researchers at Oklahoma State University conducted a 12-week, randomized controlled study of a strawberry-supplemented diet in a group of overweight/obese adults with abdominal adiposity and elevated lipid levels. Daily strawberry supplementation (as freeze-dried strawberries (FDS)) was evaluated in two amounts: a low dose (25 g FDS) equivalent to about one and three-fourths cup (250 g) of fresh strawberries, and a high dose (50 g FDS) equivalent to about three and one-half cups (500 g) of fresh strawberries. Sixty participants were randomly assigned to consume a strawberry beverage (low-dose (LD-FDS), high-dose (HD-FDS)) or a calorie- and fiber-matched control beverage (LD-C, HD-C) daily for 12 weeks as a snack to their usual diet.
After 12 weeks, high-dose strawberry supplementation (HD-FDS) was shown to significantly reduce total and LDL cholesterol levels and NMR-derived small LDL particle concentrations as compared with the lower-dose strawberry group. Both the low- and high-dose strawberry supplementation were shown to be equally effective in decreasing lipid peroxidation compared with the control groups, as measured by malondialdehyde (MDA), a well-established marker of oxidative stress. As the first 12-week study to report the total and LDL cholesterol-lowering effects of a higher amount of strawberries in obese adults, the researchers suggest that a strawberry-supplemented diet may be of clinical significance as a nutritional strategy to help reduce cardiovascular disease risk.
Basu A, Betts NM, Nguyen A, Newman ED, Fu D, Lyons TJ. Freeze-dried strawberries lower serum cholesterol and lipid peroxidation in adults with abdominal adiposity and elevated serum lipids. J Nutr. Published ahead of print March 26, 2014 as doi: 10.3945/jn.113.188169. http://jn.nutrition.org/content/early/2014/03/25/jn.113.188169.abstract