Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Randomized Controlled Trial to Investigate the Impact of a Low Glycemic Index (GI) Diet on Body Mass Index and Obesity Related Cardiovascular and Hormonal Factors in Chinese Adolescents
Brief Summary: Epidemiological studies suggest a role for a low glycemic index (GI) diet in the management of obesity and associated metabolic risks including diabetes. However, evidence from long-term, randomized controlled trials exploring the relationship between low GI diet, weight reduction and glycemia, particularly in children and adolescents, is lacking. Modern food-processing technology has produced many food products with high GI which may contribute to the burgeoning epidemic of obesity worldwide. Since dietary habits are shaped in early life, adolescence is a critical period to educate our young people to acquire a healthy eating habit to prevent obesity.

The investigators hypothesized that, in Chinese adolescents, low GI diet results in greater reduction in body mass index and body fat percentage, enhanced insulin sensitivity and favorable changes of cardiometabolic risk factors compared to conventional diet after 12 months of intervention.

This study is a randomized controlled trial of a low GI (\<55) versus conventional Chinese diet (GI\>/=70) in adolescents (12-month intervention followed by a 6-month observational period) to study; 1) the changes in body mass index and obesity associated changes in cardiometabolic profile; 2) the underlying hormonal factors associated with these changes.


Options:
A: Inclusion Criteria

* Body mass index (BMI) between 27 and 40 kg/m2
* Weight stable for last 2 months
* Not actively on a weight loss plan
* No plans to move from the area over the next 2 years
* Willing to accept random assignment

Exclusion Criteria

* Pregnant or breastfeeding
* Within 6 months of giving birth or planning to become pregnant in the next 2 years
* Diabetes (type 1 or 2) or history of gestational diabetes
* Renal or liver disease, active neoplasms, or recent myocardial infarction
* Hyper- or hypothyroidism
* Lipid lowering medications or medications known to affect weight/energy expenditure
* Excessive alcohol intake (self-reported, \> 3 drinks/day)
* Postmenopausal, including surgical menopause
* Currently under psychiatric care or severely clinically depressed (\> 17 on Beck Inventory)
B: Inclusion Criteria:

* SBP of 120 to 159 mmHg and DBP less than 100 mmHg at study entry (mean over three screening visits) (note: participants with stage 2 hypertension \[SBP greater than 160 mmHg or DBP greater than 100 mmHg\] based on the mean over three screening visits will be excluded, as will participants with a mean SBP greater than 170 mmHg or DBP greater than 105 mmHg at any one visit)
* Overweight or obese, as defined by a body mass index (BMI) greater than 25 kg/m2
* Willing to eat at least one on-site meal per day, 5 days per week, and willing to eat study diets and nothing else during controlled feeding periods

Medication Exclusion Criteria:

* Symptomatic ischemic heart disease (e.g., angina pectoris)
* Regular use of medications that raise or lower BP during the 2 months prior to study entry
* Use of a lipid lowering agent in the 3 weeks prior to study entry
* Unstable dose of hormone replacement therapy, thyroid hormone replacement therapy, and psychotropic medications known to cause weight gain or affect the outcome variables (unstable is defined as a change in dose within 2 months of study entry)
* Use of insulin, oral hypoglycemic agent, lithium, oral corticosteroid, anti-psychotic drugs, weight loss medications, nitrate, or digitalis

Medical History Exclusion Criteria:

* Active or prior CVD (e.g., stroke, heart attack, percutaneous transluminal coronary angioplasty, coronary artery bypass graft, congestive heart failure, symptomatic ischemic heart disease \[angina\], or arteriosclerotic cardiovascular disease-related therapeutic procedure)
* Diabetes mellitus
* Cancer diagnosis or treatment in the 2 years prior to study entry (note: people with non-melanoma skin cancer, localized breast cancer, or localized prostate cancer can enroll if they did not require systemic chemotherapy)
* Active inflammatory bowel disease, malabsorption, or major gastrointestinal resection
* Renal insufficiency as determined by a serum creatinine greater than 1.2 mg/dL for women or greater than 1.4 mg/dL for men (these participants can enroll if their estimated glomerular filtration rate is greater than 40 mL/min by either the Cockcroft-Gault equation or the simplified Modification of Diet in Renal Disease equation)
* Emergency room visit or hospital stay for asthma or chronic obstructive pulmonary disease in the 6 months prior to study entry
* Any serious illness not otherwise specified that would interfere with participation

Laboratory Exclusion Criteria:

* Fasting LDL cholesterol greater than 220 mg/dL and triglycerides greater than 750 mg/dL
* Fasting blood glucose greater than 125 mg/dL
* Serum transaminase greater than 2 times the upper range of normal, or a clinical diagnosis of hepatitis
C: Inclusion Criteria:

* Age between 15 and 18 years (inclusive)
* Male or female of Chinese ethnicity
* Body mass index \>/= 95th percentile of Hong Kong local age- and sex-specific reference
* No major medical illness
* Not on any chronic medications
* Post-pubertal as ascertained by clinical assessment by endocrinologist
* Willingness to give written informed consent by participants and his/her parents/guardian

Exclusion criteria:

* Concurrent participation in any clinical trial, dietary intervention or weight loss program
* Concomitant intake of weight reducing agent
* Active and uncontrolled endocrine diseases including hypo- or hyperthyroidism, Cushing's syndrome, diabetes mellitus, etc.
* Significant renal impairment, defined as serum creatinine \>150 umol/L and/or estimated glomerular filtration rate \<60ml/min/1.73m2
* Significant liver impairment, defined as \>2 times upper limit of alanine aminotransferase and asparate aminotransferase levels
* Gastrointestinal problems that would prevent them from following the test diets
* Active malignant disease
* Pregnant or lactating
* Any medical illness or condition including known non-compliance, as judged by the investigators as ineligible to participate the study
D: Inclusion Criteria:

Non-obese women aged 25-45 years

Exclusion Criteria:

Physician-diagnosed thyroid disease or diabetes or who were menopausal or any other disease that could be influenced by intervention

Answer: C