Task: Question Answering
Input (English): Background Paragraph: Although some lipids in the diet are essential, excess dietary lipids can be harmful. Because lipids are very high in energy, eating too many may lead to unhealthy weight gain. A high-fat diet may also increase lipid levels in the blood. This, in turn, can increase the risk for health problems such as cardiovascular disease. The dietary lipids of most concern are saturated fatty acids, trans fats, and cholesterol. For example, cholesterol is the lipid mainly responsible for narrowing arteries and causing the disease atherosclerosis. 
Story: Two groups of people followed different diets. Group A was comprised of vegans, while group B had a regular diet, with the mention they ate a lots of fatty foods and fast-food. 
Question: Which group was less exposed to unhealthy weight gain?
Output (English): Group A.