Please select the eligibility criteria that correspond to the clinical trial below.
Title: Lifestyle Intervention Study
Brief Summary: 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, psychological and lifestyle factors that predict the success of weight loss and weight loss maintenance.


Options:
A: Inclusion Criteria:

* Age: 18 - 65 years
* BMI: 30,0 - 39,9 kg/m2
* Owner of a smartphone
* Caucasian
* No severe diseases
* Informed written consent

Exclusion Criteria:

* Diabetes mellitus
* Severe cardiovascular and/or respiratory disease
* Untreated high blood pressure
* Severe kidney disease
* Active cancer (or in remission)
* Inflammatory bowel disease
* Severe chronic infections and/or inflammations
* Severe mental-health disorders
* Neurodegenerative disorders
* Endocrine diseases
* Lipedema
* Pregnancy and lactation
* Vigorous weight fluctuations (\> 5 kg) in the last 3 months
* Immobility
* Surgery in the last 3 months
* Participation in other intervention studies
* Carrier of pace makers
* Blood donation or transfusion in the last 3 months
B: Inclusion Criteria:

* All patients must be under the care of medical specialists who adheres to national guidelines for morbid obesity or pre-diabetic conditions.
* Age older than 18 years.
* Body max index (BMI): ≥ 30 mg/m2.
* Pre-diabetic condition following ADA criteria: fasting plasma glucose level from 5.6mmol/L (100 mg/dL) to 6.9mmol/L (125 mg/dL).
* Patients must be able to participate, understand and complete questionnaires in Spanish language.
* Patients must refer to be used to use multimedia platforms such as PDAs, tablets, laptops, smart phones or personal computers in a regular basis.

Exclusion Criteria:

* Any mental (e.g. cognitive impairment, severe psychopathology not stabilized) or physical condition that could interfere with the successful application of the research protocol.
* Patients will be recruited from specialist outpatient consultation at Vall d'Hebron Research Institute (VHIR). All patients must be under the care of specialists who adhere to national guidelines.
C: Inclusion Criteria:

* BMI 30-45
* Weight stable
* Own a Smartphone and be willing to install our Smartphone app
* Willing to conduct video conference calls with study staff

Exclusion Criteria:

* Enrolled in any formal weight loss program
* Taking anti-obesity medications
* Not taking medications that may cause weight gain
* Unstable medical conditions
* Diabetes requiring insulin supplementation
* Crohn's Disease
* Diagnosis of obstructive sleep apnea requiring intervention (i.e., CPAP)
* Assistive devices for mobility
* Hospitalizations for a psychiatric disorder within the past 5 years
* Cardiovascular disease symptoms while performing moderate intensity exercise
* Pregnancy, trying to get pregnant, or lactating.
* Bulimia or binge eating disorder
* Reports of active suicidal ideation
* Current substance abuse or dependence besides nicotine dependence
D: Inclusion Criteria:

* age: 50-75y old
* BMI ≥25 and ≤45 kg/m2
* a diagnosis of prediabetes AND/OR fasting glucose 100 mg/dL and/or HbA1c 5.7% OR Type 2 Diabetes diet-controlled and/or treated with metformin AND meeting 2 or more of the following metabolic syndrome criteria:

  * diagnosis of hypertension on stable medication regimen
  * blood pressure \>120/\>80 mmHg
  * A diagnosis of dyslipidemia on stable regimen
  * triglycerides 150 mg/dL
  * HDL cholesterol men \<40 mg/dL and women \<50 mg/dL
  * waist circumference men: \>102 cm (\>40 in); women \>88 cm (\>35 in)
* in possession of a smart phone (iPhone or Android)
* 70% of days with logging adherence (2 or more log entries/day separated by at least 5h)
* Sleep duration 6-h, with habitual self-reported wake up time \>5AM and before 11 AM and average self reported bed time \<2AM
* habitually eat breakfast
* with weight stability within 5% of screening for the last 3 months
* English speaking (the App has not yet been translated)
* must live in the New York City metro area

Exclusion criteria:

* sleep disorder, e.g. known obstructive sleep apnea (OSA) on CPAP, severe OSA with apnea-hypopnea index \>30 events/h, significant daytime symptoms of OSA, periodic limb movements of sleep, narcolepsy, current shift work or in last 6-mo, travel more than 1 time zone during intervention; severe insomnia with score 15 on Insomnia Severity Index
* significant organ system dysfunction/disease: severe pulmonary, kidney or cardiovascular disease; evidence of active illness (e.g., fever)
* history of seizure disorder
* previous bariatric surgery or on weight loss medication
* history of or current significant food intake or psychiatric disorder
* use of dietary supplements and/or medications known to affect sleep, circadian rhythms or metabolic function
* smoking tobacco or using illegal or recreational drugs
* consume excessive alcohol (women: \>14 drinks/wk; men: \>21 drinks/wk)
* anemia (hemoglobin \<10 g/dl and hematocrit \<30%)
* have conditions that render individual unable to complete all testing procedures \[e.g., unable to stay overnight or frequent travel across 1 time zones\]
* extreme early and late chronotypes (\> 2AM bed time and wake up time before 5AM and \> 11AM)
* severe food allergies
* unwilling/unable to provide informed consent

Answer: A