In the London/FPA Oral Contraceptive Trial, 800 women were given over 50 combinations of seven progestogens and two oestrogens. Low doses caused bleeding and pregnancies; high doses caused depression and amenorrhoea. Peak dose effects, for venous changes and thrombosis, headaches and migraine, and aggressive moods, matched dose-dependent changes in endometrial blood vessels and enzymes. At a Migraine Clinic, attacks decreased 10-fold when hormones, smoking and ergotamine therapy were discontinued. Headaches were virtually eradicated when patients also carried out exclusion diets and those with hypertension became normotensive. Abnormally high or low serum immunoglobulin A, G and M levels tended to return to within reference ranges. Both men and women with headaches and migraine tend to have deficiencies of zinc in sweat and serum and/or of magnesium sweat and erythrocytes which respond to supplementation ( p 0.005). Common foods caused most vascular and 'allergic' type reactions among patients with higher serum copper/zinc ratios. Both the pill and HRT increase copper levels in serum, sweat and hair ( p 0.0001). High ratios relate to abnormal antipyrine clearance, impaired liver function and clearance of polluting carcinogens. Lung cancer is superseding breast cancer as the main cause of death in middle-aged women in countries where both hormone taking and smoking are prevalent.