Farmers who tear up hedgerows may be destroying a source of new medicines for treating heart disease.
According to Ann Walker of Reading University’s Department of Food Science and Technology, a number of plant extracts, including that from the hedgerow favourite, the hawthorn (Cragaegus laevigata) could have positive medicinal effects. Walker and her team are studying the effects of non-nutrient phytochemicals found in hawthorn berries on volunteers with mildly raised blood pressure. She says that antioxidant nutrients and phytochemicals can play a key role in maintaining a healthy cardiovascular system.
A recent study carried out in the Netherlands showed that the flavonoids found in apples, black tea and onions reduce the risk of heart disease in elderly men. “Compounds, including flavonoids, from hawthorn have a dilatory effect on large and small arteries” says Walker, “causing an increase in blood volume, which reduces pressure”.
Almost all of the studies on hawthorn have been carried out in Germany on heart failure cases and this has given hawthorn a continental reputation as a herb with powerful action on the heart. However, the constituents of hawthorn are similar to those found in foods, so physiological action is mild. Indeed, practitioners of herbal medicine regard hawthorn as a tonic herb – it also has some bizarre pagan roots – that is suitable for long term treatment of even the mildest hypertension.
Walker reckons that, compared with new synthetic drugs, a shorter R&D time is required to produce proven herbal extracts that work. “Herbal medicines, as well as having a traditional history of use going back over the centuries, are used by practitioners of phytotherapy on a daily basis. Hence clinical trials can be started straight away.”
Synchrobite: The Hawthorne effect is the psychological principle that any group that is singled out for study or consideration will perform better for knowing that it has been so selected.
This item appeared first in Issue 3 of Elemental Discoveries in February 1997, see our announcement in the CHEMED-L archives.