Obesity, Overweight
Conditions
Keywords
Obesity, Chronic inflammation, Anti-inflammatory dietary intervention, Genetic susceptibility
Brief summary
The number of overweight and obese children has increased in Ireland at a greater rate than worldwide trends. The poor eating patterns that drive adolescent obesity leads to an increase in the number of unhealthy inflammatory hormones and fats circulating in the blood which increase an adolescent's risk of developing diabetes and heart disease later in life. Dietary patterns have changed whereby key nutrients that are found in fruit, vegetables and fish, which are known to have beneficial effects and reduce risk of obesity and diabetes in later life, may need to be replaced. This project will determine whether a key anti-inflammatory nutrient supplement taken for 8 weeks will improve the metabolic profile of adolescents aged 13-18 years old. Detailed cellular analysis will determine the cellular and molecular mechanisms to provide a thorough explanation of the health effects of this intervention.
Detailed description
The emerging model of obesity and diabetes is characterised by sub-acute chronic inflammation and insulin resistance. Mechanistic data indicates inflamed adipose tissue with increased infiltration of immune cells that generate pro-inflammatory cytokines. With childhood obesity in Ireland increasing at a rapid pace, it is important to establish the role of a non-pharmacological dietary approach to decreasing the sub-acute chronic inflammation seen in overweight and obese children. Several foods contain nutrients that are known to have anti-inflammatory properties. Such foods including fish, fruits and vegetables are known to be deplete in the adolescent diet. The aim of this project is to investigate whether a nutritional supplement containing anti-inflammatory nutrients, n-3 polyunsaturated fatty acids (found in fish oil), vitamin C, vitamin E, and polyphenols found in green tea and tomato; will improve metabolic phenotype in 13-18 year old teenagers over an 8-week period. Further, to provide insight into the role of genetics in the development of metabolic dysregulation and response to dietary treatment.
Interventions
DIETARY_SUPPLEMENTSupplement containing fish oil, vitamin C, alpha-tocopherol, green tea extract and lycopene
1 x fruit juice fortified with salmon oil containing 1000mg EPA and 1000mg DHA daily for 8 weeks AND 4 x film-coated tablets containing 561mg vitamin C, 389mg alpha-tocopherol, 416mg green tea extract and 15mg lycopene daily for 8 weeks in conjunction with a weight management programme
DIETARY_SUPPLEMENTPlacebo supplement
1 x fruit juice fortified fortified with high oleic sunflower oil daily for 8 weeks AND 4 x film-coated placebo tablets daily for 8 weeks in conjunction with a weight management programme
Sponsors
National Children's Research Centre, Ireland
University of Dublin, Trinity College
The Adelaide and Meath Hospital
St. James's Hospital, Ireland
University College Dublin
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
13 Years to 18 Years
Healthy volunteers
No
Inclusion criteria
1. Male or female 2. 13-18 years 3. Body mass index ≥ 91st percentile on UK growth reference charts (Cole, 1995) 4. Medications/dietary supplements which do not interfere with the intervention are allowed, on condition that the participants adhere to the same regimen during the intervention, including oral contraceptives and other non-fatty acid based dietary supplements (e.g. garlic) 5. Smoker or non-smoker 6. Not participating in any other intervention study
Exclusion criteria
1. Pregnancy or lactation 2. Endocrine disorders such as Polycystic Ovary Syndrome 3. Currently on treatment for a chronic inflammatory condition such as asthma 4. Kidney or liver dysfunction 5. Iron deficiency anaemia 6. Prescribed anti-inflammatory medication 7. Consumers of fatty acid supplements including fish oils, evening primrose oil and antioxidant vitamin (A, C, E, -carotene) supplements 8. High consumers of oily fish (\> 2 servings/week) 9. Participants planning to start a special diet or lose weight (e.g. Slimfast, Atkins etc) 10. Weight change ≥3kg within the last 3 months 11. Alcohol or drug abuse (based on clinical judgement) 12. Participants with an allergy to fish and/or shellfish
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Homeostasis model of assessment - insulin resistance | 8 weeks | Homeostasis model of assessment - insulin resistance (HOMA-IR) will be derived from fasting glucose and insulin concentrations \[(fasting plasma glucose x fasting serum insulin)/22.5\] as determined by Matthews et al., 1985 |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Adiponectin | 8 weeks | Adiponectin, a marker of insulin sensitivity, will be determined pre- and post-intervention. |
| Markers of inflammation | 8 weeks | Markers of inflammation such as C reactive protein, interleukin (IL) - 6, IL-1β, tumour necrosis factor alpha, intra-cellular adhesion molecule-1, vascular cell adhesion molecule-1, retinol binding protein 4, fibrinogen, white blood cells and related inflammatory markers |
| Lipid Profile | 8 weeks | Full lipid profile and lipidomic analyses (total triacylglycerol, non-esterified fatty acids, total cholesterol, LDL cholesterol, HDL cholesterol and plasma fatty acid composition, diglycerides, cholesterol esters and sphingomyelins,) and related lipid markers |
| Inflammatory genetic variants | 8 weeks | Inflammatory genetic variants such as complement component 3, lymphotoxin- α, IL-6, IL-1β, TNF-α, adiponectin polymorphisms and related variants that link to the inflammatory phenotype |
| Functional molecular analysis (ex-vivo) | 8 weeks | Functional molecular analysis will be conducted to determine which insulin sensitising pathways have been modulated by the intervention |
Countries
Ireland
Outcome results
None listed