The scientists at Manchester Metropolitan University believe liquid garlic could prevent the damage to the eyes, kidneys, blood vessels and skin of diabetes patients caused by high sugar levels in a process known as glycation.
"Garlic in its liquid form has proved a potent block on glycation in a series of in-vitro tests we have conducted," said Dr Nessar Ahmed, molecular biologist at the university's department of biological sciences.
"We are trying to understand why sugars destroy the body from the inside and have a particular interest in natural products and their therapeutic benefits."
The researcher is one of many looking at whether a natural product can help prevent diabetes or play a role in the treatment of the disease. Diabetes increased by one third during the 1990s due to the prevalence of obesity and an ageing population. If nothing is done to slow the epidemic, more than 333 million people in the world could have the disease by 2025, according to the International Diabete Federation.
Garlic is already one of the best-selling herbal dietary supplement products in the United States, and in some European markets such as Germany and the UK, where sales increased 13 per cent in 2002. There are thought to be more than 2,200 credible scientific papers on all aspects of garlic, including its chemistry, pharmacology, and clinical applications.
"One of the other things that people with diabetes have is increased free radical activity which can also have a role in these complications," said Dr Ahmed.
Garlic's antioxidant properties - thought to fight free radicals - ave been widely studied. It may also lower cholesterol levels, often hig in diabetics.
Dr Ahmed's team will carry out a clinical trial on 70 patients with type 2 diabetes at a hospital in Saudi Arabia. The researcher recently discovered that the key ingredient in aged garlic extract, s-allylcysteine, slowed the glycation process.
Other British scientists have recently found that a compound extracted from garlic is effective against even the most antibiotic-resistant strains of MRSA, the 'hospital superbug' that now kills thousands of patients in the UK each year.