Too many carbohydrates, especially the simple, sweet sugars, can make you fat. Complex sugars like fiber, on the other hand, are an important factor for our health. Unlike simple sugars, we cannot easily digest these fibers in vegetables and grains. They are thought to work like a lubricant that moves our food more quickly through our bodies. This way the body has less time to extract energy and thus, we stay slim. Prof. Dr. Jan-Hendrik Hehemann from the University of Bremen suspects that complex sugars – so-called polysaccharides – from ocean algae could have a similar function in the marine carbon cycle. The German Research Foundation (DFG) is now supporting his work with a Heisenberg Professorship.