Black currants are even higher in anthocyanins than blueberries. (Photo by Marylise Doctrinal)
You've probably heard a million times that berries are good for you, but how many of us know how they really benefit health?
Here's one good example: they improve cholesterol levels. Or, to be more specific, it's the anthocyanins in berries that do. A new study found that daily anthocyanin supplementation significantly increased HDL while decreasing LDL (link). In this post, we'll take a closer look at the paper.
The study included 120 subjects aged 40-65 years with dyslipidemia. Dyslipidemia generally refers to a poor lipid profile and can mean either high LDL, high triglycerides, low HDL, or a combination of these. A high total cholesterol alone does not necessarily count as dyslipidemia.
At the beginning of the study, the participants had total cholesterol levels around 225 mg/dL, LDL around 159 mg/dL, HDL around 46 mg/dL, and triglycerides around 200 mg/dL.
The subjects were given 320 mg anthocyanins or placebo daily for 12 weeks. The supplements contained 17 different anthocyanins extracted from bilberry and black currant. The participants were instructed to take the supplements twice per day (2 x 160 mg) 30 minutes after breakfast and supper and to maintain their usual diet and lifestyle.
Serum HDL cholesterol increased significantly more in the anthocyanin group (13.7%) than in the placebo group (2.8%) after 12 weeks of treatment. Serum LDL cholesterol decreased by 13.6% in those who consumed anthocyanins and increased by 0.6% in those who received placebo. No significant differences were seen in total cholesterol and triglyceride levels.
In other words, while total cholesterol levels were similar between the groups, the lipid profile of those who ate anthocyanins was much better. Their HDL levels increased and LDL levels fell significantly, while in the placebo group only a slight improvement in HDL was seen. Here's a quote from the authors:
The 13.6% decrease in LDL and 13.7% increase in HDL observed in the present study would result in a nearly 27.3% reduction in coronary heart disease risk, which is meaningful and greatly promising.
No changes were observed in weight, BMI, waist/hip circumference, and blood pressure between the groups. Furthermore, anthocyanin consumption had no effect on red and white blood cell counts and hemoglobin.
Anthocyanins from berries or supplements?
So what about eating berries instead of taking supplements? According to one source, black currants contain 476 mg anthocyanin per 100 grams on average, while blueberries contain 386 mg (link). A second source says black currants contain 254-434 mg (link), while another source reports an anthocyanin concentration between 84-114 mg in blueberries (link), and yet another 62 mg for blueberries and 300 mg for bilberries (link).
According to the USDA database (link), raw blueberries contain about 160 mg anthocyanins and frozen blueberries about 90 mg. Wild raw blueberries take the blueberry cake with 320 mg, but raw bilberries are even better with 430 mg anthocyanins per 100 grams. Raspberries and strawberries contain a measly 20-40 mg, depending on whether they're frozen or fresh.
To make some sense out of this, it seems that blackcurrants and bilberries have the most anthocyanins, followed by blueberries. A cup of any of these berries per day would come pretty close to the amounts used in the study. Strawberries and raspberries are a distant third.
Keep in mind that these figures are not carved in stone, as it's impossible to give an exact calculation of how much anthocyanins a cup of berries will give you. The variation in anthocyanin content is very high, and the actual amount depends on the cultivar and also when and where the berries are picked. It's useful to know, however, that the concentration of anthocyanin actually increases with ripening, and that while freezing does destroy some of the anthocyanins, most of them survive the process (link).
Anthocyanins increased HDL and decreased LDL by more than 13% in subjects with dyslipidemia. The anthocyanins were extracted from bilberry and black currant and given in supplement form, 160 mg taken twice daily after breakfast and supper for a total of 320 mg.
A cup of black currants, blueberries or bilberries (frozen or fresh) would give roughly the same amount of anthocyanins as the supplements used in the study.
For more information on cholesterol, see these posts:
Niacin Raises HDL, Lowers LDL, VLDL & Triglycerides
Blood Test Analysis: The Cholesterol and Saturated Fat Issue Revisited
Coconut Lowers LDL, VLDL and Triglycerides, Raises HDL
Low-Carb vs. Low-Fat: Effects on Weight Loss and Cholesterol in Overweight Men