Dietary reference values (DRVs) for energy are based on estimating the total energy expenditure (TEE) for groups of people. TEE provides a measure of the energy requirement at energy balance i.e. when energy intake matches energy expenditure. The methodology to measure TEE - the doubly labelled water (DLW) method - has advanced and as a result, the evidence base on TEE in a wide variety of population groups has expanded considerably. With the high levels of overweight and obesity currently seen in the UK and the wealth of new data now available, it was considered timely for the Scientific Advisory Committee on Nutrition (SACN) to review recommendations for the UK population. This report details the evidence and approaches SACN have considered in order to update the DRVs for energy. SACN chose a prescriptive approach to estimating energy reference values; suitable reference body weight ranges consistent with long-term good health were used to calculate energy reference values. Thus, basal metabolic rate (BMR) values were predicted using healthy reference body weights. Using this approach, if overweight groups consume the amount of energy recommended for healthy weight groups, they are likely to lose weight, whereas underweight sections of the population should gain weight towards the healthy body weight range. SACN has derived new energy reference values. For most population groups, except for infants and young children, the values have increased. DRVs should be used to assess the energy requirements for large groups of people and populations, but should not be applied to individuals due to the large variation in physical activity and energy expenditure observed between people.