New research in the UK is investigating the theory that drinking milk can help the body fight viral infections and diseases including cancer, the BBC reports this week. There is growing evidence that conjugated linoleic acid (CLA), a type of fat found in cow's milk, can improve the immune system. Scientists at the UK Universities of Southampton and Reading are conducting a human trial, the first of its kind, to investigate whether CLA can help the body to fight off bacterial infection, and even reduce the growth of tumours. If the health benefits of CLA are proven it could lead to the development of a new functional food range of milk, butter and cheese products marketed as a way to reduce the risk of contracting cancer as part of a healthy diet. Project leader Dr Philip Calder, of the University of Southampton, said: "We want to find out what happens to the immune system if we give people an increased amount of CLA in their diet. "One of the reasons CLA might protect against cancer is it improves the ability of the immune system to seek out and destroy tumours. "We will be testing out two different forms of CLA, which we believe are the most important, giving people three increasing doses over a six-month period to find the type and dose that produces health benefits." During the three-year trial scientists will also work with the dairy industry on modifying feeding practices to produce cow's milk with the right form and level of CLA.