The humble red onion, commonly used in Indian and Mediterranean cuisine, can help prevent heart disease, scientists have claimed. Researchers at the Chinese University in Hong Kong found that red onion helps remove bad cholesterol from the body, which is responsible for heart attacks and strokes. It also retains the body’s good cholesterol that in turn helps protect against heart disease, they said.
Zhen Yu Chen, who led the research, said: “Despite extensive research on onions, little is known of how their consumption interacts with human genes and proteins involved in cholesterol metabolism within the body.”
“Our study was therefore undertaken to characterise the interaction of onions with enzymes in an attempt to explore the underlying cholesterol-lowering mechanism,” Zhen further added. “This study is the first of its kind to investigate the interaction of red onions with biological functions.” For their study, the scientists fed crushed-up red onions to hamsters who had all been put on a high-cholesterol diet.
They found that after eight weeks, levels of bad cholesterol, or low density lipoprotein (LDL), had dropped by an average of 20 per cent. But over the same time period there was no reduction in the hamsters’ high cholesterol levels, also known as high density lipoprotein (HDL), they said.
“The results support the claim that the regular consumption of onion reduces the risk of coronary heart disease,” said Zhen. Although white onions are by far the most popular type in Britain, red onions are widely used in India, the Middle East and the Mediterranean. Onions have long been known to have many health benefits including preventing cancer, heart disease and common coughs and colds. It has been found that some parts of the world where onion consumption is high have even been shown to have much lower cancer rates.
For example in Georgia, the US, where the small, sweet Videlia onion is grown the number of stomach cancer diagnoses are a half the average for the rest of the cancer. In China, where people eat more onions and garlic than anywhere else in the world, the risk of stomach cancer is 40 per cent lower than average.