While our findings are in contrast to the large European studies which failed to find an interaction between FTO and dietary carbohydrate intake on obesity [14, 44, 45], a study in 4,895 Swedish individuals [30] showed a significant interaction (Pinteraction = 0.0004); however, the effect allele of the FTO SNP rs9939609 (strong LD with rs8050136) increased the risk of obesity among those with low carbohydrate and high fat intakes. This evidence concerns the gene FTO and obesity due to melanocortin 4 receptor deficiency.