Eating grapefruit may be able to help you lose weight, as long as you burn more calories than you consume. If you wish to begin eating grapefruit for weight loss, you need to talk to your health care provider first, especially if you are on any medications, as some can have serious interactions with grapefruit.

The Grapefruit Diet was first introduced in the 1930s by Kelly D. Brownell, PhD, according to the website Grapefruit-Diet. The plan was designed so that dieters could lose a substantial amount of weight in a short amount of time. Over time, various versions of the diet have emerged. Plans commonly suggest eating half a grapefruit before each meal.

Proponents of the Grapefruit Diet claim that grapefruit promotes weight loss by reducing appetite, increasing fluid loss and promoting fat-burning. The Grapefruit-Diet website states that it is possible to lose up to 10 pounds in 12 days while eating normal meals at normal times. The Grapefruit Diet is a very low-calorie diet -- 800 to 1,000 daily -- which mimics starvation to the body, according to the UCLA Center For Human Nutrition.

Followers of the Grapefruit Diet should follow a sensible eating plan and engage in daily physical exercise, according to the Grapefruit-Diet website. They should not skip meals. They should eat dinner at least two hours before bed time because your body does not burn as many calories at rest. They should not eat very hot or cold foods or cook food in aluminum pans. The plan calls for three to four daily servings of carbohydrates, four to six servings of fruit, two to four servings of vegetables, one to two servings of dairy and two servings of protein.

Eating half of a fresh grapefruit eaten before meals may be associated with significant weight loss, according to a 2006 study published by K. Fujioka and colleagues in the "Journal of Medicinal Food." After 12 weeks, those in the study who had ate half of a fresh grapefruit group before each meal had lost 1.6 kilograms. Those who drank grapefruit juice had lost 1.5 kilograms, those who took grapefruit capsules had lost 1.1 kilograms and those who took placebo had lost 0.3 kilograms.

Grapefruit and grapefruit juice can interfere with some prescription medications, according to the National Institutes of Health Clinical Center. These interactions can cause serious health problems. Taking your medications and consuming grapefruit at different times of day does not eliminate risk. Examples of some medications that are known to interact with grapefruit include buspirone, amiodarone, sertraline, saquinavir, carbamazepine, nifedipine, nimodipine, nisoldipine, cyclosporine, sandimmune, tacrolimus, sirolimus, simvastatin, lovastatin and atorvastatin.