Should people only eat when when they are hungry or should they follow a meal schedule?

Debatable: There are circadian rhythms unique to us. Body processes require nutrition to provide energy for these processes. Depending on need and activity, we get the urge to eat. Some believe frequent balanced meals take away hunger and level out Insulin levels. Feedback mechanisms are smoothed. Others believe you should eat only when hungry and quit when satisfied. Hard to know. I favor the former.

Eat small meals: It is important to start the day with a healthful breakfast. Eating 6 meals spread out over every 2-3 hours prevents overeating, plus eating several small meals with an emphasis on fruits and vegetables has also been shown to decrease the risk of cardiovascular disease, to boost the metabolism, while helping maintain energy levels.