Research suggests that Salvestrols are produced by plants in response to fungal infection, and are therefore most present at the sites where fungi are likely to attack. In fruits, this means on the skin, as the fruit is ripening. Salvestrol compounds are also present on the surfaces of the roots of many plants, as the roots are continually under threat from fungi in the soil.

It is estimated that we consume today about 10-20% of the Salvestrols which would have occurred in the diet 100 years ago. So, even though we are being urged to eat more fresh fruit and vegetables, unless you eat organic you are unlikely to get sufficient Salvestrols from your diet.