Human Evidence
There have actually been human studies on Calorie Restriction that have demonstrated the predicted results:
In 1991, there was a scientific study undertaken with humans sealed in an enclosed “artificial” environment, with the intention of testing a self-sustaining environment which could mimim that of underground, or outer space situations. These 8 scientists were planned to live in the the Biosphere for 2 years. These scientists lived under a low-calorie diet of fruits, vegetables, grains, nuts, and beans with only a small amount of meat, eggs and dairy.
Over the course of the experiment, the average weight loss was 18 percent. ADDITIONALLY — blood pressure went down 25%, and cholesterol and blood sugar levels were significantly lowered. These effects were similar to those in animal studies that had been put under a calorie-restricted diet.