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:

* 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
B: Inclusion Criteria:

* Ages 8-16 years old
* BMI \>95th percentile for age/gender based on CDC
* Both primary caregiver/parent and child must agree to participate in the nutrition classes

Exclusion Criteria:

* endocrinopathies, including hypothyroidism and diabetes
* Psychiatric disorders that will interfere with ability to complete follow-up and adherence to protocol
* Any behavioral or psychosocial issue that will interfere with subject's completion of program, including eating disorder.
* Any use of medication (steroids, for ex.) that contributes to excess adiposity.
* Any use of pharmacological intervention for weight management, including prescription medications, over-the-counter medications, or herbal supplements.
* Any concurrent membership in a weight management program.
* Inability or unwillingness of parent to accompany the child to nutrition classes.
* Pregnancy
C: Inclusion Criteria:

* child aged between 12.0 and 17.0 years,
* child BMI =/\> 98th percentile,
* first language is English (or fluent in English)
* parent/s willing to participate in the programme with their child
* completion of written informed consent and/or assent prior to any study-specific procedures

Exclusion Criteria:

* severe intellectual difficulties,
* obesity secondary to genetic condition,
* limitations to engaging in physical activity
* use of medication known to effect body weight;
* limitations to using a smartphone device
* known family issues that would affect general compliance and attendance at follow-up visits.
D: Inclusion Criteria:

* Enrolled in grade 9 or 10
* BMI ≥ 85th percentile for age and gender
* Residing in predominately one household, with access to a working telephone
* Consumption of 12 fluid ounces sugar-sweetened beverages (including 100% fruit juices) per day

Exclusion Criteria:

* Sibling participating in the study
* Intention to change location of residence during the 2 years post-randomization
* Plans to be away from home for 5 weeks or longer during the study period
* Physician diagnosis of a major medical illness or eating disorder
* Chronic use of any medication that may affect body weight or composition
* Current smoking
* Physical, mental, or cognitive handicaps that prevent participation

Answer: A