January 23/Berlin/Obesity -- To curb the appetite, close the cookbook, turn off the cooking show and step away from the food porn. That is the message from a new study out of Germany which found that the mere sight of delicious food caused levels of the appetite-controlling hormone ghrelin -- also known as the hunger hormone -- to spike in their male subjects.

In the study out of the Max Planck Institute of Psychiatry, published in the journal Obesity, scientists measured the levels of appetite-controlling and metabolism hormones like ghrelin, leptin and insulin in male subjects as they were shown photos of either delicious foods or non-edible objects.

 When presented with visual stimulation of food images, scientists observed that levels of ghrelin, which is secreted by stomach cells and tells the brain when to eat, spiked.