The expanding number of overweight people across the globe has increased the demand for new and effective anti-obesity drugs. While some weight loss drugs have fallen out of favour with consumers, others have been removed from sale, either because they’re not effective or because they have dangerous side-effects. Examples of the latter include amphetamines, fenfluramine and dinitrophenol (DNP).
DNP was originally produced as an explosive for artillery shells during the First World War. In 1933 Maurice Tainter, a Stanford University pharmacologist, discovered that when DNP is ingested it leads to rapid fat loss – as much as 1.5 kg per week. This revelation soon gained DNP widespread popularity as a weight loss aid, but it soon became clear that taking it was really dangerous
Weight loss drugs work by reducing food intake, reducing calorie absorption and/or increasing metabolic rate. DNP induces weight loss by massively raising metabolic rate, hijacking oxidative phosphorylation and causing all but a few cells to convert calories into heat rather than store it as adenosine triphosphate (ATP).
Respiration takes place in three stages: glycolysis, the citric acid cycle and oxidative phosphorylation. The latter is the most efficient form of respiration, yielding the most molecules of ATP per calorie. DNP reduces this efficiency, putting the body in an...