"A study by David Jenkins, MD, PhD—the University of Toronto pioneer in low-glycemic eating — demonstrates that eating small portions at frequent intervals is good for your health in a number of remarkable ways. Within the study, they found that people who ate every three hours reduced their blood cholesterol by over 15% and their blood insulin by almost 28%. That's key, because in addition to regulating your blood sugar level, insulin plays a pivotal role in fat metabolism, inflammation and the progression to metabolic syndrome. When your body produces less insulin, you're much less likely to convert dietary calories into body fat.

Also some research shows that the human body is primed to consume most of its calories during daylight hours. But the lifestyle is problematic for many: Because family meals and dinners with friends often are scheduled for after sunset, "people who try to stop eating after 7pm can’t do it every day for the rest of their lives," says Dr. Seltzer, who supports an alternative strategy: Eating a hearty meal at your regular dinnertime.
If you're not up for crunching numbers every day, you can take a more generalized approach. “For some people, it’s knowing, ‘Typically I eat a whole sandwich,’” says Gagliardi. “Now, I’m going to eat half a sandwich at lunch and save the other half for my dinner and cut my calories in half." To get started, consider these 25 ways to cut 500 calories a day.
Based on the concept of caloric density, which states that some foods have few calories in proportion to their size (say, a lettuce), while others have lots of calories packed in small portions (a regular chocolate chip cookie comes to mind), Volumetrics divides foods into 4 categories based on their calorie/volume ratio, and is perfect for people looking to binge on some foods while still shedding pounds. However, as with the calorie counting approach, Volumetrics does not take into account the quality of the calories, prioritizing quantity instead. The app Noom and Weight Watchers (both reviewed above) share similarities with this diet theory.