Appetite Suppression Effects of an Herbal Combination of Yerba maté, Guarana, Damiana (YGD), and 12 Other Herbal Components, Versus YGD Supplementation Alone

Background:

Supplementation with the combination of Yerba maté, guarana and damiana (YGD) has been found to slow gastric emptying by 15 to 58%, and to induce a substantial weight loss over 45 days without changes in diet. Enhanced gastric emptying rate has been shown to reduce the satiating effect of food and may thereby promote obesity. Yerba maté and guarana are known to contain large amounts of caffeine, resins, saponins and tannins, whereas damiana contains ethereal oils, tannins and resins. Caffeine belongs to a class of compounds called methylxanthines and epidemiological studies suggest that caffeine might possess weight reducing properties. The sympathomimetic properties of caffeine act to some extent through α- and β-adrenoreceptors, but most of the sympathoadrenergic stimulation caused by caffeine (even in very small doses) acts through the dual ability to antagonise adenosine and to inhibit the activity of cellular cyclic nucleotide phosphodiesterase. Stimulation of the sympathetic nervous system can cause suppression of hunger, enhance satiety and increase of energy expenditure covered in part by increased fat oxidation.

Aim:

To evaluate the effect of YGD combination or Akavar 20-50 (A20-50) compared with placebo on:

1. Acute change in 4-h subjective appetite sensations
2. Acute change in ad libitum energy intake (EI) 30 minutes post intake
3. Acute change in serum glucose, insulin, ghrelin and other appetite-regulating hormones (glucagon-like peptide-1 (GLP-1), cholecystokinin (CCK))

Subjects:

19 , healthy, premenopausal, overweight to obese (BMI between 27 and 32 kg/m2) women(age: 18 to 45 years).

Method:

The study is designed as a 3-way crossover, randomized, placebo controlled, double-blind study.

The bioactive components will be administered as capsules containing YGD or A20-50. The placebo capsules will contain rice flower. The subjects will undergo following treatments:

1. YGD capsules
2. A20-50 capsules
3. Placebo capsules

On each test day the subjects will be instructed to rest in a supine position for 15 minutes before dual measures of blood pressure and HR. A blood sample will be taken (baseline). The subject's appetite sensations will also be assessed by visual analogue scales (VAS) prior to intake of the test compound. Immediately hereafter the subjects will be served the first dose of the test compound. Blood samples will be taken at 15 and 30 minutes (time 0) post test compound. After 30 minutes post test compound the subjects will be given a standard breakfast (2.5 MJ = 598 kcal). Additional blood samples will be taken 15 minutes 30, 45, 60, 90, 120, 150, 180 and 240 minutes post-meal, together with a VAS appetite score assessment (0, 30, 45, 60, 90, 120, 150, 180 and 240 minutes).

Immediately after the last blood collection subjects will be asked to take a second dose of the test compound. After 30 minutes the subjects will repeat one VAS score assessment and be served an ad libitum lunch.

Blood samples will be analyzed for insulin, glucose, and appetite regulating hormones such as glucagon-like peptide-1 (GLP-1), ghrelin, cholecystokinin (CCK).


Eligibility Criteria:
Inclusion Criteria:

* Healthy,
* BMI: 27-32 kg/m2,
* Weight stable (within +/- 3 kg) two months prior to study inclusion,
* Non-smoking,
* Nonathletic (\< 10 h hard physical activity),

Exclusion Criteria:

* BMI \<27 and \> 32 kg/m2,
* Change in smoking status,
* Daily or frequent use of medication,
* Suffering from metabolic diseases,
* Suffering from psychiatric diseases,
* Suffering from any other clinical condition, which would make the subject unfit to participate in the study,
* Hemoglobin \< 7.0 mmol/l.
* alcohol and drug abuse
* blood donation, 3mo prior to the present study and during study participation