Going on a five-day fast—where calorie intake is reduced to just 750 to 1,100 calories a day—can have tremendous benefits for your health. Research shows that a five-day fast every three months can help to reduce risk factors for heart disease while lowering levels of inflammation, which can be the forerunner of a range of chronic diseases, such as cancer and diabetes. On top of that, the periodical five-day fast has been shown to help people lose an extra few pounds and trim an inch or two off the wasteline.