Obesity rates have skyrocketed globally over the last few decades. Obesity presents a public health emergency because of its numerous associated comorbidities. Waist-to-height ratio is a useful add-on to body mass index (BMI) to quantify health risks and monitor progress. The causes of obesity are complex and they necessitate a degree of empathy from healthcare professionals caring for those with the condition. Researchers believe that the obesity epidemic will not begin to improve without significant governmental policy changes. Many weight loss diets exist, but no diet stands out as more favourable at the one-year follow-up mark, as maintenance of the weight lost is uncommon. This article discusses the physiology of weight changes, emphasising the crucial role of energy balance. Energy density is a useful concept for patients to understand to help identify foods which will fill them up and help facilitate a reduced energy intake. Protein and fibre are also highlighted as focus nutrients. Exercise is important for various reasons, but on its own will not usually lead to weight loss. Sleep is an often neglected yet important factor to consider in obesity management.