The freeze-dried strawberry powder, reportedly a concentrated source of polyphenolic flavonoids, fibre and phytosterols, was found to reduce total and LDL cholesterol levels by 5 and 6 per cent, respectively, according to findings published in the Nutrition Journal.
Furthermore, levels of malondialdehyde - a marker of oxidative stress – also decreased by about 14 per cent, report researchers led by Arpita Basu from Oklahoma State University.
The study involved 16 women with three features of the metabolic syndrome, a condition characterised by central obesity, hypertension, and disturbed glucose and insulin metabolism.
“To our knowledge this is the first study investigating the effects of freeze-dried strawberry powder supplementation on selected cardiovascular risk factors in women with metabolic syndrome,” wrote the researchers.
“Serum cholesterol levels were lowered following four weeks of freeze-dried strawberry consumption, which suggests a need for further study to determine if this might be a potential dietary approach to lowering cholesterol levels in obese women,” they added.
High cholesterol levels, hypercholesterolaemia, have a long association with many diseases, particularly cardiovascular disease (CVD), the cause of almost 50 per cent of deaths in Europe, and reported to cost the EU economy an estimated €169bn ($202bn) per year.
Study details
The Oklahoma-based scientists asked the 16 women to drink two cups of a drink made from a freeze-dried strawberry powder (25 grams) every day for four weeks. The strawberry powder was supplied by the California Strawberry Commission.
In addition to the significant improvements in total and LDL-cholesterol levels, and malondialdehyde levels, a decreasing trend was also reported to levels of oxidized-LDL after four weeks.
“The decreasing trend in oxidized-LDL in our study bears consideration and further research,” said the researchers. “Because oxidized-LDL plays a critical role in the initiation and progression of atherosclerosis, long-term supplementation of antioxidant-rich fruits, like strawberries may be beneficial in slowing or reversing the process of atherosclerotic cardiovascular disease in obese women with metabolic risk factors.”
On the other hand, no changes in levels of inflammatory markers such as C-reactive protein were recorded.
Mechanism
Commenting on the potential mechanism, the researchers noted that the phytosterol, fibre, or phytochemical content may contribute to the benefits, all of which have been shown to lower cholesterol levels in other studies.
“Freeze-dried strawberry powder, a concentrated source of strawberry polyphenolic flavonoids, fibre, and phytosterols is a novel dietary fruit supplement marketed by selected fruit growers and special promotion groups,” wrote the reserahcers. “Not enough scientific data is available on the health benefits of this product.
“Our study shows the potential role of FSP in lowering total and LDL-cholesterol, and lipid peroxidation in women with metabolic syndrome, and suggests the need for larger controlled trials,” they concluded.
Source: Nutrition Journal
2009, 8:43, doi:10.1186/1475-2891-8-43
"Freeze-dried strawberry powder improves lipid profile and lipid peroxidation in women with metabolic syndrome: baseline and post intervention effects"
Authors: A. Basu, M. Wilkinson, K. Penugonda, B. Simmons, N.M. Betts, T.J. Lyons