The question of how diet affects health is complex. This is in part due to the number of lifestyle factors involved. Many patients need to be surveyed to produce statistically significant information that offers meaningful insights.
The UK Womens Cohort Study (UKWCS) does this by investigating information about diet submitted to the World Cancer Research Fund by 35,000 women. The study is led by Professor Janet Cade, head of Leeds Nutritional Epidemiology Group.
Researchers sent questionnaires to women aged 35 to 69 across England, Scotland and Wales. They included similar numbers of women who eat a vegetarian diet, a diet that includes fish, and a diet that includes meat. The resulting cohort was tracked to investigate, initially, links between different types of cancer and diet. The cohort has been tracked for the last 20 years.
Results have shown an association between meat intake and increased risk of breast cancer. They have also found a reduced risk of pre-menopausal breast cancer in women whose diet contains more fibre.
Researchers also used the data to track links between diet and risk of other diseases, including heart disease and stroke. They identified that cereal fibre might offer some protection against stroke, particularly among women who were overweight.
The data is still being mined, with recent results showing how diet might affect the age at which women go through menopause.
The next phase of the project is to link the data in the Womens Cohort Study to other data sources to investigate new associations. This could include exploring how diet might influence cancers according to their hormone receptor status. The team is also linking up with NHS Digital to access information on hospital admissions. They look at links between diet and a wide range of other health outcomes, such as diabetes, Alzheimers disease, or hip fractures.
Professor Cade said: For the first time we are going to be able to explore how food and nutrient intake and other lifestyle habits might affect a whole range of health outcomes.
Our aim is to put this wealth of information into a national database that can be mined by researchers all over the world.