“The reduction in blood pressure is not trivial, it is the same as gained from taking pills.

“What we do not know is if garlic works as well as pills over the long term or if it would reduce the risk of heart attack or stroke. But I was surprised at the extent of blood pressure reduction seen with garlic.

“There is no harm in taking garlic along with other lifestyle factors such as eating less red meat, less salt, less alcohol and taking more exercise and also continuing to take blood pressure medication.”

People can reduce blood pressure by cutting their intake of salt, losing weight and getting fit. 

But many still need to be placed on medication to reduce their blood pressure readings to the safe level of 140/90.

In the last decade, an increasing number of studies have suggested that a compound found in garlic could help reduce vascular problems, including blood pressure.

But it remains unclear whether benefits only come from taking garlic supplements, or whether they can be derived from eating raw garlic or even using it in recipes.

The latest research by a team in Australia looked at all of these studies to decide if they showed adequate evidence that garlic reduces hypertension.

Dr Karin Ried, of the University of Adelaide, examined 11 studies in which patients were randomly assigned to garlic or a placebo.

The higher a person’s blood pressure was at the beginning of the study, the more it was reduced by taking garlic.

Dr Rosemary Leonard, the Daily Express doctor, said: “Anyone could benefit from regular doses of garlic, but it is important not to assume that taking supplements is all you need to treat high blood pressure.

“If you have high blood pressure and are overweight, then it is important to take regular exercise and eat a healthy diet.

“High salt intakes are also a major contributor to high blood pressure, so people should monitor what they are eating and also keep an eye on the hidden salt in processed foods.

“Everyone ought to have their blood pressure measured regularly and those overweight, or who have the condition running in their family, should keep a close eye to ensure it does not become an issue.”