Personalized Nutrition and eHealth: Lifestyle Intervention (LION) Study for Weight Loss Maintenance

Despite standardized intervention strategies, weight loss and weight loss maintenance largely differ from person to person. Factors which may contribute to these individual differences is current object of research. In order to investigate predictors and barriers for weight management and to investigate two different dietary interventions and two different digital tools for weight maintenance, the LION-Study was designed as follows: Step I (screening, baseline phenotyping), step II (weight loss intervention with formula diet), step III (weight maintenance intervention with 4 intervention groups: low carb/newsletter; low carb/app; low fat/newsletter; low fat/app) and step IV (follow-up). Participants are required to attend visits at seven time points. At screening (month 0) a telephone-based screening interview takes place, in order to test eligibility of the potential participant. If the person is eligible, two consecutive baseline face-to-face visits are planned during step I. After completion of the eight weeks weight loss intervention (month 3), an additional visit takes place followed by three consecutive visits in the weight maintenance step (month 6, 9 and 15). The study ends with a final visit after the follow-up (month 27). Additional contacts (face-to-face and telephone) take place during the weight loss intervention step. Participants will regularly receive a bag with the required formula diet meals. During these "pick up" appointments, the study team actively get in face-to-face contact with participants. At the different visits, data are collected by questionnaires, medical investigations (e.g. MRI, motor function, resting metabolic rate), blood withdrawal as well as urine, feces and saliva sampling. Primary objective is to evaluate the effect of two diets (low carb/low fat) and two digital tools (app/newsletter) on long-term weight loss maintenance 12 months after weight loss. Secondary objective is to identify genetic, epigenetic, physiological, p