The truth about fat.

Dr Saleyha Ahsan presents the 3rd episode in a series on nutrition, aiming to discover the ‘truth’ about fat. She meets with a team of volunteers in Aberdeen to undertake experiments about fat. First, 4 volunteers consume meals with different types of fat and a blood sample is taken. Dr Emilie Combet explains the results. Ahsan uses herself as an example of someone with too much body fat and has an MRI scan to illustrate the effects on her body. The volunteers take part in the ‘Big Fat Challenge’; they cannot consume any food with more than 1% fat for a week. Dietician Lucy Jones explains the fat content of a range of foods. Dr Andy Connelly explains how fat improves the taste of food through an experiment with skimmed and full-fat milk. Ahsan looks at the effects of fat on the brain with Dr Fabian Grabenhorst, concluding that humans are ‘hardwired to love fat’ due to the reaction in the ‘pleasure’ centre of the brain. Ahsan visits sports scientist Jacky Forsyth to find out how much fat is burned through exercise, and discovers the most effective methods. She then meets with Dr James Brown at the medical school of Ashton University, where they examine and explain the purpose of human body fat. Ahsan discovers more about the household fats such as oil and lard with the assistance of Lucy Jones, including the difference between saturated and unsaturated fat. The ‘dangerous’ relationship between fat and cholesterol is explained. This is complicated by the ‘contradictory’ news stories about the potential benefits of saturated fat. Dr Nita Forouhi at Cambridge University presents her research related to diabetes which indicates that there are different types of saturated fats, and that some are beneficial. Ahsan explains the benefits of Omega-3 fat, and visits London’s Billingsgate Market to examine the oil content of fish with Professor Doug Techer. She then meets with Dr Carol Llewellyn at Swansea University, who aims to use Omega-3-rich algae as a source. Professor Liam Sinclair explains to Ahsan about feeding algae to farm animals that will go on to produce Omega-3-rich dairy products. Finally, Ahsan returns to the volunteers at the end of their diets, and they are tested by Professor Jane Ogden. Ahsan concludes that fats are a necessary part of a healthy diet.