Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Randomized Controlled Study on the Incretin Effect, Cognitive Function and Controlled Fasting During Bed Rest in Healthy Male Volunteers
Brief Summary: Bed rest produces insulin resistance in healthy volunteers. In this study the investigators aim to investigate the effect of 8 days bed rest on the incretin effect and how alternate daily fasting affects cognitive function and the insulin resistance produced by bed rest.

The subjects will be randomized to either 3 meals a day (isocaloric diet), alternate daily fasting or one meal/day every second day (25% of daily calorie need) and four meals/day every second (175% of daily calorie need).

The investigators hypothesize:

1. Bed rest reduces the incretin effect
2. Alternate daily fasting improves the cognitive function (memory and concentration) compared to isocaloric diet
3. Alternate daily fasting reduces insulin resistance produced by bed rest compared to isocaloric diet


Options:
A: Inclusion Criteria:

* The participants in this study will be 50 men and women in the 30 to 65 year age range, who have a BMI in the high normal to moderately obese range (i.e. 24 to 35 kg/m2),
* Participants who are eating usual US diets and are sedentary to moderately active (i.e. not exercise trained).

Exclusion Criteria:

* History of any chronic disease process that could interfere with interpretation of results
* Smoking, pregnancy, alcoholism, psychiatric problems, life situations that would interfere with study participation and compliance.
B: Inclusion Criteria:

* Body mass index in the range of 22.0 - 27.0 kg/m2,
* Fasting blood glucose \<110mg/dL (without medication)
* LDL-cholesterol \<180 mg/dL (without medication)
* Blood pressure \<140/90 mmHg (without medication)
* Stable weight (change \<± 10%) for 3 months immediately prior to the study,
* No history of metabolic disorders or cardiovascular disease
* No acute or chronic inflammatory disorder
* No current medications to regulate blood sugar, blood pressure or lipids or hormones
* No heavy drinking (more than 15 drinks/week)
* No use of tobacco or recreational drugs within past 5 years
* No dietary restrictions (e.g. vegetarianism and vegan)

Exclusion Criteria:

* Known Malignancy
* Women who are pregnant, breast-feeding or trying to become pregnant
* History of any chronic disease process that could interfere with interpretation of study results
* Women or men on hormonal supplementation or anti-conceptive hormonal medication for at least 2 months
* Therapy with antidepressants within past 6 months
* Regular therapy with acetylsalicylic acid
C: Inclusion Criteria:

* BMI\<25kg/m2
* VO2 max normal for age

Exclusion Criteria:

* Tobacco smoking
* Alcohol ingestion \> 14 units per week
* Diabetes in nearby relatives
* Resection of the small intestine
* History of gastric bypass surgery
* Risk of deep venous thrombosis
* Female
D: Inclusion Criteria:

* Aged \>35-75 years
* Waist circumference above cut-off for high risk of cardio-metabolic disease of \>102 cm in men with a Europid, Black African and Caribbean, and other ethnic background and \>88 cm in women with a Europid, Black African and Caribbean, and other ethnic background (WHO, 2008), and ≥90 cm in men and ≥80 cm in women with an Asian background (South Asian and East Asian) (Misra et al., 2009).

REFERENCES Misra A, Chowbey P, Makkar BM, Vikram NK, Wasir JS, Chadha D, et al. (2009). Consensus statement for diagnosis of obesity, abdominal obesity and the metabolic syndrome for Asian Indians and recommendations for physical activity, medical and surgical management. The Journal of the Association of Physicians of India 57: 163170.

WHO (2008). Waist circumference and waist-hip ratio: report of a WHO expert consultation. Geneva, 8-11 December 2008.

Exclusion Criteria:

* Kidney or cardiovascular disease, cancer, diabetes, gastrointestinal or chronic liver disease;
* previous bariatric surgery or other major surgery (e.g. organ transplantation);
* unable to provide written informed consent;
* have significant psychiatric disorder (e.g. schizophrenia, anxiety, panic disorder, attention deficit disorder, post-traumatic stress disorder, obsessive compulsive disorder) or uncontrolled depression;
* participated in a weight management drug trial in the previous 3 months;
* have binge eating behaviour;
* have uncontrolled epilepsy;
* alcohol or substance abuse;
* currently pregnant, lactating, or planning pregnancy within the study period;
* are using medication clinically deemed to affect metabolic rate and weight (e.g. beta blockers, corticosteroids, diuretics, etc);
* lactose intolerant.

Answer: C