The impact of carbohydrates, proteins and fatty acids as major components of daily nutrition on the development of metabolic illnesses is an objective of numerous clinical studies. However, the effect of an isocaloric diet on metabolism is less investigated and not well understood. This study aims to reveal genetic determinated metabolic responses to an isocaloric high carbohydrate, low fat diet versus an isocaloric low carbohydrate, high fat diet in healthy twins. This study generates information for further detailed nutrigenomic analysis. Twins receive an isocaloric diet rich in carbohydrates (55% carbohydrates, 15% protein, 30% fat) with dietary counselling for 5 weeks and afterwards with nutrients supplied for 6 days, followed by an isocaloric diet rich in saturated fat (40% carbohydrates, 15% protein, 45% fat) for 6 days with nutrients supplied and for 4 weeks with dietary counselling and again followed by another 6 days when nutrients were supplied. Anthropometry, blood tests and energy expenditure are performed after the period of diet rich in carbohydrates (Carb), after the first 6 days (HFshort) and at the end of the period of diet rich in fat (HFlong).
This is an intervention study in healthy adult twins with the aim to investigate the genetic determination of metabolic responses towards an isocaloric high carbohydrate, low fat diet versus an isocaloric low carbohydrate, high fat diet.