Impact of Phenylketonuria-type Diet on Appetite, Appetite Hormones and Diet Induced Thermogenesis

University of Glasgow

Status: Completed

Conditions: Phenylketonuria (PKU)

Treatments: Dietary Supplement: Phenylketonuria-type diet; Other: Normal (control) diet

Study type: Interventional

Funder types: Other

Identifiers

NCT02440932

200130139

Details and patient eligibility

About

Low-phenylalanine diets are commonly prescribed to people with phenylketonuria (PKU), an inborn disease which causes accumulation of amino acid phenylalanine (Phe) in the blood. High blood Phe levels can cause mental, behavioural, neurological, and physical problems. Thus, low-phenylalanine diets help patients to manage their condition but it is not clear whether they have an impact on appetite, energy intake and changes in body weight. This is important to explore as prevalence of obesity in this population is rising high. This study aims to find out the effect of PKU-type meals on appetite, appetite biomarkers, and post-meal energy expenditure. The investigators will recruit 26 healthy adults and ask them to participate in two experimental trials. On one occasion the participants will be asked to consume a PKU-supplemented drink followed by a PKU type-lunch and on another occasion the supplement and lunch will be based on normally consumed foods. Series of blood samples will be taken and appetite will be assessed during both experiments. Both experimental trials will finish with consuming an "all-you-can-eat" buffet.

Enrollment: 26 patients

Sex: All

Ages: 18 to 45 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Healthy adult
2. Body weight stable for previous 4 months
3. Regular menstrual cycle (females)

Exclusion criteria

1. Pregnancy or lactation (females)
2. History of eating disorder
3. History of gastrointestinal problems or surgery
4. History of allergy
5. History of chronic illness
6. On any medication
7. Smoking
8. On nutritional supplements
9. Following specific diet
10. Currently taking part in other research

Trial design

26 participants in 2 patient groups

Phenylketonuria-type diet

Experimental group

Description:

Breakfast: one pouch of amino acid supplement (174 mls supplemented drink PKU cooler 20, Vitaflo®; 20 g protein, 9.4 g carbohydrates, 0.7 g Fat) Lunch: cheese sandwich \[low protein bread (Juvela, UK), no protein vegan cheese (Viotros, UK)\], low protein crackers (Vitaflo, UK), and low protein cookies (Juvela, UK). Dinner: ad libitum buffet meal

Treatment:

Other: Normal (control) diet

Dietary Supplement: Phenylketonuria-type diet

Normal diet

Other group

Description:

Breakfast: 174 ml of milk (20 g protein, 9.4 g carbohydrates, 0.7 g Fat) Lunch: cheese sandwich, crackers, and cookies (regular foods) Dinner: ad libitum buffet meal

Treatment:

Other: Normal (control) diet

Dietary Supplement: Phenylketonuria-type diet