The effects of high-protein breakfasts.

High protein diets cause a thermogenic effect and increase satiety. When people are satiated, energy intake will be restricted. A positive energy balance, can be prevented because of the addition of extra proteins to the breakfasts. During the next meal energy intake will be less, because people might be satiated and still full. Also the energy expenditure will be increased by the extra proteins which also prevents a positive energy balance.
The additional green tea during one of the interventions also causes a thermogenic effect. Green tea contains different components which inhibit particular enzymes. Through this the symphatic activity is increased and also the energy expenditure.

The administration of a whey protein/ alphalactalbumine/ green tea mixture to a standardized yogurt breakfast, will cause an increase in post-prandial energy expenditure, due to diet-induced thermogenesis and an increase in satiety within 5 hours.

One testday is 5 hours. 30 minutes before the intervention the energy expenditure is measured and after the intervention energy expenditure is measured for 4,5 hours. Satiety is measured every hour and 1 hour after the intervention even every 20 minutes.

Subjects will eat 4 different breakfasts. Subjects will come to the university once a week for 4 consecutive weeks. There energy expenditure will be measured by means of indirect calorimetry (ventilated hood). Also, satiety is measured with visual analog scales. Randomization will determine in which sequence the subjects will receive the interventions. This are the interventions:

1. placebo yogurt (15% proteins, 47% carbohydrates and 38% fat);

2. placebo yogurt + whey protein (41% proteins, 47% carbohydrates and 12% fat);

3. placebo yogurt + alphalactalbumine (41% proteins, 47% carbohydrates and 12% fat);

4. placebo yogurt + green tea catechins (15% proteins, 47% carbohydrates and 38% fat).




The breakfast consists of 20% of the daily energy intake and is subject specific.