Study backs berries for heart health benefits
 
08-Feb-2008 - A diet rich in berries may boost levels of good cholesterol and improve blood pressure, indicating their potential benefits for heart health, says a new study from Finland.

Consumption of bilberries, lingonberries, black currants and strawberries led to systolic blood pressure (BP) reductions of 7.3 mm HG, while levels of HDL cholesterol rose by over five per cent, according to the results of the single-blind, randomised, placebo-controlled intervention trial published in this month's American Journal of Clinical Nutrition.

"We used a combination of different berries, instead of only one berry type, to ensure a high intake of various polyphenols and to minimize the intake of other bioactive components obtained from the individual berry types," wrote lead author Iris Erlund from the Department of Health and Functional Capacity and the National Public Health Institute in Helsinki.

"According to the intake and bioavailability data obtained in this study, polyphenols and vitamin C are the most likely berry constituents to exert effects in vivo after the consumption of berries," she added.

The study adds to an ever-growing number of reports in the literature linking berry consumption to a range of health benefits, including lowering LDL cholesterol levels, and protecting against cancer and neurodegenerative diseases like Alzheimer's.

Erlund and co-workers, including researchers from the Finnish Red Cross Blood Service and MTT Agrifood Research, recruited 72 middle-aged subjects (average age 58.0, average BMI 26.2 kg per sq. m, 46 women) and randomly assigned them to consume a moderate amount of berries or control products for eight weeks.

The berry group consumed 100 grams of whole bilberries and 50 grams of a lingonberry-rich nectar every other day. In addition, they consumed 100grams of purée of blackcurrants or strawberries and a juice of raspberry and chokeberry on the other days. Meanwhile, the control group received one of four different products, including sugar-water, sweet rice porridge, marmalade sweets, or sweet semolina porridge.

At the end of the two month period, Erlund and co-workers report that levels of HDL-cholesterol rose significantly by 5.2 per cent in the berry group, compared to a 0.6 per cent increase in the control group. Total cholesterol and triacylglycerol levels were not altered, however.

In addition to improvements in blood pressure, the researchers note that consumption of the berry-rich diet was associated with an 11 per cent inhibition of platelet function, compared to a 1.4 per cent augmentation in the control group, as measured with a platelet function analyser.

"In conclusion, we found favorable changes in platelet function, blood pressure, and HDL cholesterol after the consumption of berries for two months," wrote the researchers.

"The findings are important, because they may partly explain the CVD-protective role of a diet rich in fruit and vegetables. Other types of studies are now warranted to identify the compounds and mechanisms that are responsible for the observed effects," they concluded.

Iris Erlund told NutraIngredients.com that the research was ongoing. "Next, we aim to investigate different types of berries separately to find out which berries are most effective," she said.

"Also, we need to find out how much berries should be consumed to see effects. On the whole, I think that berry health research is still only in its beginning world-wide," added Erlund.

Cardiovascular disease (CVD) causes almost 50 per cent of deaths in Europe, and is reported to cost the EU economy an estimated €169 billion ($202 billion) per year.

Source: American Journal of Clinical Nutrition
February 2008, Volume 87, Number 2, Pages 323-331
"Favorable effects of berry consumption on platelet function, blood pressure, and HDL cholesterol"
Authors: I. Erlund, R. Koli, G. Alfthan, J. Marniemi, P. Puukka, P. Mustonen, P. Mattila, A. Jula