Clinical trials with blackcurrants
Decreases blood cholesterol and blood pressure
A) Clinical trial subjects with high cholesterol levels consumed anthocyanin (320mg) equivalent to 6 tablespoons of blackcurrant berries daily, over a period of 12 weeks.
The results showed:
- Blood pressure decreased significantly compared to the base line.
- HDL ("good") cholesterol increased and LDL("bad") cholesterol significantly decreased compared to the placebo group.
B) In another study, subjects who drank 250ml pure blackcurrant juice each day for a week showed a modest but significant decrease in cholesterol accumulation in macrophage foam cells that form plaque attached to arteries.
DECREASEs VASCULAR INFLAMMATION
A 2009 study showed increased intake of blackcurrant and orange juice decreased vascular inflammation and the risk of cardiovascular disorder.
The trial subjects with peripheral arterial disease consumed a daily drink of 250ml of blackcurrant juice and 250ml of orange juice. This trial gave highly significant results after four weeks.
- 11% decrease in C-reactive protein
- 3% decrease fibrinogen
These substances are both indicators of vascular inflammation. Lower levels of both markers indicate lower risk of cardiovascular disease. The study supports the view that increased intake of fruit products such as blackcurrant and orange juice decreases the risk of cardiovascular disease.
REDUCES RISK FACTORS ASSOCIATED WITH METABOLIC SYNDROME
This 2010 Finnish study showed that a mixture of berries, including blackcurrants, may be linked to a reduction in the risk of cardiovascular disease.
Nonalcoholic fatty liver disease is commonly associated with 'metabolic syndrome' ( risk of heart disease, high blood pressure, type 2 diabetes, obesity) . This study examined liver markers to assess liver damage caused by accumulation of fat in the liver. Two groups of slightly overweight women were recruited. The group that incorporated the berry mixture into their diet for 20 weeks showed a 23% reduction in the levels of the liver marker ALAT (alanine aminotransferase) that indicates liver damage. Researchers concluded that enhancing liver function over the long term may lead to decreased risk of cardiovascular disease.
INCREASES BLOOD FLOW
A) Subjects consumed anthocyanin (100mg) equivalent to two tablespoons of blackcurrant berries.
- Anthocyanin content of plasma reached a maximum after 1 hour, and decreased to 50% by 4 hours.
- After 1 hour the forearm blood flow increased significantly (about 40%) compared to placebo.
B) In another study 50mg of anthocyanin was shown to improve blood circulation in cold hands.
Hands were soaked in cold water at 10℃ for 1 minute. For subjects who had consumed blackcurrants, hand temparature returned to normal after 7 minutes, compared to 13 minutes for the placebo group.
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