Effectiveness of 5-Hydroxytryptophan on Satiety in a Randomised, Placebo Controlled, Time Blinded Study, in Overweight Women
Trial Snapshot
- Phase
- Phase 2
- Status
- Completed
- Sponsor
- Enrollment
- 24
- Locations
- 2
- Primary Endpoint
- satiety scores (visual analog scores)
Study Overview
Brief Summary
The aim of the study is to show evidence of the efficacy of 5-HTP to induce satiety and to reduce food intake (confirmatory study).
The primary objective of the present study is to determine:
- the effectiveness of a 5-HTP preparation on satiety markers (before intake of a meal and during the day)
The secondary objectives of the present study are to determine the effectiveness of a 5-HTP preparation on:
- food consumption (amount and composition) during a free meal (dinner);
- wellness after one week supplementation;
- the intermeal interval;
- body weight and waist-hip ratio (WHR).
Detailed Description
One of the physiological factors regulating the food intake pattern is satiety. Satiety is defined as the absence of ingestive motivation, which ends when the next meal is initiated (Blundell et al., 1996). Food intake affects a number of physiological objective parameters in blood known to be involved in signalling satiety, such as glucose (Melanson et al, 1999; Chapman et al, 1999; Campfield et al, 1996), insulin (Speechly et al, 2000) and cholecystokinin (CCK) (Gutzwiller et al., 2000; Beglinger et al., 2001; French et al., 2000; Degen et al., 2001; Burton-Freeman et al., 2002, 2004). More recently, the gastric hormone ghrelin was identified as a marker for hunger and meal initiation (De Graaf et al., 2004).
Humans do not only eat in response to a metabolic or physiological need. Humans also respond to a significant extent to other internal subjective and emotional signals (clues). The exact relations between the physiological internal signals and subjective and emotional internal signals are not known. Besides also external and social factors modulate physiological-derived hunger and satiety signals.
Though the regulation of food intake has been studied quite extensively, the underlying mechanism is not elucidated yet and still new factors involved in this regulation are being found. It is known that the macronutrients such as lipids, proteins and carbohydrates affect satiety differently, but this mechanism is still not very clear either.
Nowadays, more and more food supplements become available suggesting to affect hunger and satiety sensations, resulting in the long-term in weight loss. For example dietary fibres are known for their satiating effect.
The food supplement 5-HTP is used for this purpose as well. The food supplement, already available in the United States and in Italy, has been investigated for multiple indications such as migraine, depression, anxiety, fibromyalgia, hypertension, insomnia and obesity.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Treatment
- Masking
- Double
Eligibility Criteria
- Ages
- 18 Years to 65 Years (Adult, Older Adult)
- Sex
- Female
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Healthy as assessed by:
- •The TNO health and lifestyle questionnaire
- •Physical examination
- •Females aged 18 through 65 years on Day 01 of the study
- •Body mass index (BMI) 25 - 32 kg/m2 (if enough subjects are available, subjects with a BMI 25 - 30 kg/m2 will be included first).
- •Regular and normal Dutch eating habits (consuming mostly three main meals including breakfast) as assessed by the questionnaire on health and lifestyle
- •Non-restraint eaters, defined by a score of < 3.4 on the Dutch Eating Behaviour Questionnaire
- •Using oral contraceptives for > 3 months (only fixed phase)
- •Voluntary participation
- •Having given written informed consent
- •Willing to comply with the study procedures
- •Willing to agree to the use of all nameless data, including publication, and the confidential use and storage of all data for at least 15 years
- •Willing to agree to the disclosure of the financial benefit of participation in the study to the authorities concerned
Exclusion Criteria
- •Subjects with one or more of the following characteristics will be excluded from participation:
- •Participation in any clinical trial including blood sampling and/or administration of pharmaceutical or nutritional substances up to 90 days before Day 01 of this study
- •Participation in any non-invasive clinical trial up to 30 days before Day 01 of this study, including blood sampling and/or oral, intravenous, or inhalatory administration of pharmaceutical or nutritional substances
- •Mental status that is incompatible with the proper conduct of the study (including depression)
- •Having a history of medical or surgical events that may significantly affect the study outcome, including metabolic or endocrine disease, especially diabetes type I or II; cardiovascular diseases (including hypertension); gastrointestinal diseases, including events that affect nutrient uptake or appetite; or using medication that may interfere with 5-HTP (antidepressants [selective serotonin reuptake inhibitors {SSRIs}, monoamine oxidase inhibitors {MAOIs}], migraine medication, or some hypertension medication).
- •Having a history of drug abuse
- •Claustrophobia
- •Alcohol consumption > 21 units (glasses)/week
- •Not willing to stop use of supplements of minerals or vitamins from screening onwards
- •Reported food allergy or sensitivity (wheat, milk, eggs, nuts, etc.)
- •Reported unexplained weight loss or weight gain of > 2 kg in the month prior to pre-study screening
- •Practicing sports > 10 hours a week
- •Reported slimming or medically prescribed diet
- •Reported vegan, vegetarian, or macrobiotic lifestyle
- •Pregnant or lactating or wishing to become pregnant in the period of the study
- •Recent blood or plasma donation (< 1 month prior to Day 01 of the study)
- •Not willing to give up blood/plasma donation during the study
- •Personnel of TNO Quality of Life (located in Zeist), their partners and their first and second degree relatives
- •Not having a general practitioner
- •Not willing to accept information-transfer concerning participation in the study; or information regarding health, like laboratory results, findings at anamnesis or physical examination, and eventual adverse events to and from general practitioner.
Outcomes
Primary Outcomes
satiety scores (visual analog scores)
Secondary Outcomes
- food intake
- wellness
- intermeal interval
- body weight and waist-hip ratio