You're determined to lose weight this time and find yourself debating whether to go low-fat or low-carb?
While more research is still needed on how a person's genotype may affect their response to certain foods or diets, the results of this study and other research still point to one proven way for people to lose weight, said Lu Qi, director of the Tulane University Obesity Research Center in New Orleans.
Further, genotype pattern and baseline insulin secretion were not associated with the dietary effects on weight loss, according to the researchers. It all depends on the person - although they haven't yet been able to determine the all important characteristics that determine which camp you fall into.
Christopher Gardner, a professor of medicine at Stanford University, says that every individual's body is unique, and we're only beginning to understand the reasons for this diversity.
About half were men and half were women.
They were also urged to consume healthy low-fat and low-carb diets, as opposed to bacon, which is low in carbs, or soda, which is low in fat.
Over the course of a year, participants were invited to 22 group sessions to help them stick to their diet.
Don't waste money on a diet plan that claims to match meals to your DNA - it won't make a difference, a new study has found.
The low-fat dieters cut things like oils, fatty meats, full-fat dairy and nuts, while the low-carb dieters cut the likes of cereals, grains, rice, starchy vegetables and legumes.
But weight loss averaged about 13 pounds throughout a year, regardless of genes, insulin levels or diet type.
Although results varied greatly among the participants - one lost 60 pounds while another gained 20 - and 200 participants dropped out before the end of the study, the results at the end were similar. Both groups were instructed to eat lots of vegetables and very few foods with added sugars, trans fats, or refined flour.
After two months they then began gradually increasing their daily carbohydrate or fat intake in small amounts in order to reach a sustainable balance.
No significant interaction was observed between diet-genotype pattern or diet-insulin section with 12-month weight loss.
The latest study made sure participants stuck to their diets so the results would be more accurate.
In the study, the researchers tracked about 600 overweight adults, ages 18 to 50, who were randomly assigned to follow either a healthy low-fat diet or a healthy low-carbohydrate diet (containing 20 grams of fat or carbs at the beginning of the study) for one year. "Maybe we shouldn't be asking what's the best diet, but what's the best diet for whom?" said Dr Gardener, who's report elucidated "there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet". "But let's cut to the chase: We didn't replicate [our previous] study, we didn't even come close".
"Carbohydrates have been deemed "fattening" and "unhealthy" when in actual fact, the science behind carbohydrates is quite complex, and demonising an entire food group is not wise", warns Rhiannon Lambert, leading Harley Street nutritionist and author of Re-Nourish: A Simple Way To Eat Well. "I still think there is an opportunity to discover some personalisation to it [dieting] - now we just need to work on tying the pieces together".