'Super Broccoli' offers anti-cancer hope
broccoli' containing over three times the normal levels of an
anti-cancer compound.
Broccoli, a member of the crucifer family of vegetables, is a rich source of sulphoraphane, which has been shown to display potent anticarcinogenic properties. However, over half of the national population fails to benefit from this because they lack a specific gene (GSTM1) that helps retain the compound in the body.
"Eating a few portions of broccoli each week may help to reduce the risk of cancer. Some individuals, who lack a gene called GSMT1, appear to get less cancer protection from broccoli than those who have the gene," said lead researcher Professor Richard Mithen.
"Our studies suggest that this may be because if you lack the gene you cannot retain any sulphoraphane inside your body - it is all excreted within a few hours."
He added that consuming larger portions of broccoli, or broccoli with higher levels of sulphoraphane, such as the 'super-broccoli', would allow those lacking this gene to retain as much sulphoraphane as those with the gene.
Eating larger portions may also have additional benefits, since broccoli is also a rich source of other vitamins and minerals.
The tissue of crucifer vegetables, which also include cauliflower, cabbage and Brussels sprouts, contain high levels of the active plant chemicals glucosinolates. These are metabolised by the body into isothiocynates, which are known to be powerful anti-carcinogens. The main isothiocynate from broccoli is sulphoraphane.
It is not all doom and gloom for those who lack GSMT1, however, since they are likely to gain more cancer protection from eating other crucifers, the researchers suggest.
But Josephine Querido, cancer information officer at British charity Cancer Research UK, said that the new study is too small to draw conclusions.
"The research backs current thinking that genetic differences may affect how we absorb nutrients from our food. But only 16 people took part in Professor Mithen's study and this is too small a number from which to draw specific conclusions."
"We know that a healthy balanced diet is an important factor in preventing cancer, especially cancers of the digestive system. But when it comes to food, there is no one particular 'super' fruit or vegetable that will protect you from cancer," she said.
The research from the Institute of Food Research (IFR) was funded by a grant from the Biotechnology and Biological Sciences Research Council, the University of Nottingham and Seminis Inc.
