Obesity treatment—are personalised approaches missing the point?

Many companies offer personalised weight loss plans tailored to our DNA, selling the idea that the effectiveness of dieting is predetermined. There is a degree of plausibility behind this, as numerous genes have been associated with increased body weight.1 In reality, the extent to which genes determine the ability to lose weight remains unclear. The study by Livingstone et al (doi:10.1136/bmj.i4707)2 represents a substantial step towards answering this, at least for the FTO gene, the allele currently associated with the largest variance in body mass index.3 The authors conducted a systematic review and meta-analysis using data from almost 10 000 participants from randomised control trials to test the relation between the FTO gene and weight loss interventions. They found no relation between the FTO gene and the ability to lose weight. This contradicts a previous meta-analysis, not based on data from individuals, which found a small but significant increased responsiveness to weight management interventions (of 0.7 kg) in people homozygous for the FTO allele.4

The authors acknowledge several limitations in their …