New research from UK-based Institute of Food Research reveals that two food components recognised for their ability to fight cancer are up to 13 times more powerful when put to work together. The findings could open up new possibilities for functional foods and food supplements.
The study at the Norwich institute focused on genes that play an important role in tumour formation, tumour progression, and the spread of tumour cells. The food components sulforaphane and selenium were found to have an increased impact on these genes when used as a combined treatment.
"As a result of this research, we hope to begin a human cancer prevention trial next year," said Dr Yongping Bao, senior researcher at the IFR.
Sulforaphane is found at high concentrations in broccoli, sprouts, cabbage, watercress and salad rocket. Selenium-rich foods include nuts, poultry, fish, eggs, sunflower seeds and mushrooms.
The plant chemical sulforaphane is recognised not only for its powerful role in cancer prevention, but also as a potentially useful curative cancer drug, the IFR continued.
The deficiency of the essential mineral selenium in the diet is associated with the incidence of many types of cancers, including prostate cancer. According to the IFR, the UK dietary intake has halved over the last 20 years and British bread-making wheat contains 10 to 50 times less selenium than that in the US and Canada.
"High concentrations in the diet are normally required to protect against cancer, but when these compounds act synergistically lower doses are needed to prevent cancer formation. This is particularly good news as selenium and sulforaphane can be toxic at high levels," continued Dr Bao.
This latest research highlights an ongoing issue in the study of food components - the complexity of interactions between food components and the limitations to studying them in isolation.
"IFR is committed to a whole food approach, reflecting the way that nutrient and non-nutrient components are eaten in every day life," said director of IFR, Professor Alastair Robertson.
Full findings are published in the latest issue of the journal Carcinogenesis.