This study examines the effect of a five-year multifactorial lifestyle intervention in the Oslo diet and antismoking study on long-term cancer risk. In 1972-1973, 1232 men with high cardiovascular risk profile were randomised to intervention including cholesterol lowering diet, weight loss and antismoking advice, or control (1:1). This study examines the effect of the intervention on 43-year cancer incidence and mortality.

The Oslo diet and antismoking study showed that a 5-year lifestyle intervention reduced the long-term risk of coronary events and mortality. The lifestyle risk factors for cancer are partly similar to those for coronary heart disease, e.g. smoking, high body weight, unfavourable diet. The investigators therefore expect that the intervention has an effect on cancer risk in the long term.

In this follow-up study, the investigators analyse the association between the intervention, and cancer incidence and mortality drawn from the Cancer Registry of Norway and the Norwegian Cause of Death Registry from the time of randomisation in 1972/3 until the end of 2015.

Inclusion Criteria:

• participated in screening of coronary risk factors, into which all men born in 1923-1932 and living in Oslo were invited in 1972-1973
• being in the upper quartile of a coronary risk score based on blood pressure, serum total cholesterol concentration and cigarette smoking

Exclusion Criteria:

• serum total cholesterol level above 9.0 mmol per Liter
• having a healthy diet, based on a short dietary history
• self-reported cardiovascular disease or diabetes
• previous history of cancer

The participants selected for this follow-up study (n=1216) are the eligible subjects of the 1232 men at high cardiovascular risk profile who participated in the Oslo Diet and Antismoking Study (included in 1972-73). Fourteen men were excluded because they did not consent to studies other than the main study, and two more because of previous history of cancer.