Double hamburger. Double hamburger containing lettuce, sliced tomatoes, sliced onions and sliced gherkins. The flag of the USA (the Stars and Stripes) is planted in the burger. Processed food such as found in a hamburger is usually low in fibre and high in fats. A low fibre diet can lead to constipation and intestinal disease. Too much fatty food can lead to obesity, and saturated fats such as found in red meat can raise blood cholesterol levels. Saturated fats are thought to cause atherosclerosis, a disease where fatty deposits develop on the inner walls of arteries increasing the risk of coronary heart disease and strokes.