Minerva

Cocaine is a potent vasoconstrictor that can cause myocardial infarction in users with or without diseased coronary arteries. Cocaine can also cause non-ischaemic chest pain, but there are still no evaluated protocols to help doctors decide who to admit, who to observe, and who to discharge. In one study, only 6% of people admitted to hospital with chest pain after using cocaine had a full-blown myocardial infarction (Academic Emergency Medicine 2000;7:873-7).

Readers who enjoy a nightcap of cocoa will be interested to know that cocoa has the same antiplatelet effects as aspirin (American Journal of Clinical Nutrition 2000;72:30-5). Flavonoids are probably responsible for the effect, which lasts at least six hours in healthy adult volunteers. The researchers made their experimental cocoa with hot water to avoid complicating the issue with milk proteins. It's still unclear what their results mean in the real world, but full fat milk, whipped cream, three teaspoons of sugar, and a Cadbury's flake on the side are unlikely to enhance cocoa's healthgiving properties.

Nobody knows how many people in Britain have food allergies, but up to a third of the population think they do. Estimates of incidence based on objective tests are more than 10 times lower, says a recent report by the …