CEO Dr Richard Walker said: 'If people change their lifestyles, this can be avoided.'
Tenovus has hired Cardiff-based Quadrant as its first external agency to promote the campaign. Walker said the agency had been briefed to run a positive campaign, rather than 'frighten people with messages of doom'.
'We will be spreading the message among UK consumers of all ages that the link between cancer and everyday activity is very real,' he said. 'For example, traditional western diets contain many high-fat foods, but many people don't know that obesity is a major risk factor for certain cancers such as ovarian cancer. We aim to show them how they should be taking care of themselves.'
Set up in 1943, Tenovus was involved in the development of breast cancer drug Tamoxifen, and was the first cancer charity to launch a freephone helpline.
It has a vaccine research facility and a diet research lab in Southampton. The organisation wants to boost its profile as a UK-wide research charity.
Other charities have used similar lifestyle campaigns, including Cancer Research UK, which was named 'most impressive UK charity at getting noticed' in a recent poll of House of Lords peers (PRWeek, 19 August).