FAIR project investigates lignans

Linseed is the richest source of lignans and rye has the highest concentration of lignans among whole-grains. These are findings of a recent EU-funded FAIR project that set out to quantify the phytoestrogen content of various foods and the variation in human metabolism, and to investigate the anti-carcinogenic (i.e. cancer preventing) effects in colon, mammary and prostate tissue.

Phytoestrogens are a group of natural components present in many vegetable foods, which may have a considerable impact on health. Recent studies suggest that phytoestrogens may play a role in preventing cardiovascular disease, osteoporosis, menopausal symptoms, breast, colon and prostate cancer.

Interest has focused on two main groups of phytoestrogens: isoflavones and lignans. Scientists working on the FAIR project, led by Professor H. Adlercreutz, University of Helsinki, analysed a variety of legumes, grains, nuts, beverages fruits, berries, and vegetables to quantify their phytoestrogen content.

Clover seed, sunflower seeds, sesame seeds, nuts (including peanuts), strawberries and pumpkin were all found to be suitable food choices to increase the phytoestrogen content of the diet. The researchers further discovered that daily ingestion of nine slices of rye crispbread for 2 weeks did not significantly reduce genetic damage in blood lymphocytes, nor was there a modulation of plasma antioxidant activity. However, in rat studies, the colon cancer preventive potential of rye but not soy was shown. They concluded that it is likely that other components of food containing these compounds are also involved in the protection.

Full findings can be obtained from Prof. H. Adlercreutz (herman.adlercreutz@helsinki.fi), at the University of Helsinki.