One of the most punishing diets ever was the Hollywood diet, consisting primarily of grapefruit, hard-boiled eggs, spinach and an occasional steak. People did lose weight, but of course no one could stay on the diet longer than about five minutes. However, it turns out that the designers of this bit of cruelty unwittingly had some right thinking on their side. A recent study showed that when people ate grapefruit before every nondietetic meal, they lost weight. Lead researcher Ken Fujioka, MD, director of nutrition and metabolism research at the Scripps Clinic, del Mar, California, assigned 100 obese men and women into one of four groups. Before each meal, one group took grapefruit extract... another drank grapefruit juice... one ate half a grapefruit... and the last group, the placebo group, had no grapefruit. The researchers also had members of each group walk at least 20 minutes two or three times a week. The results after 12 weeks showed that those who consumed grapefruit were the winning losers. Those who drank the juice lost an average of 3.3 pounds... those who ate the fruit lost 3.6 pounds on average. For those taking the extract, the average loss was 2.4 pounds... and the placebo group lost an average of only one-half pound. Is it just grapefruit that has such benefits, I wondered, or would any fruit ingested before a meal in this manner make the difference? According to Dr. Fujioka, it is possible that another fruit might create the same response, but he thinks it is more complicated and more specific to grapefruit itself. Researchers measured glucose and insulin levels and found that the grapefruit groups had lower levels of both at the end of the study. It appears that grapefruit improves insulin resistance, which in turn helps control weight. Dr. Fujioka was quick to point out to me, however, that a large group of people must avoid grapefruit and its juice because certain medications react negatively with it. (Drugs that interact include statins, calcium channel blockers for high blood pressure, a variety of antianxiety and antidepressant drugs, antiseizure drugs and protease inhibitors for HIV.) Dr. Fujioka's favorite way to eat grapefruit is peeled and in sections so that you are eating the membrane as well as the pulp. This gives the extra benefit of increased fiber. However, if that's just too much grapefruit for you, you'll be happy to know that the juice-drinking group had the same insulin benefit as those who ate the fruit and, within a whisker, the same weight loss.