What were the eating and dietary habits followed by the Messenger of Allah, peace and blessings be upon him, and his companions?

From his guidance (peace and blessings be upon him) regarding eating: saying "Bismillah" (in the name of Allah) at the beginning, which is obligatory; saying "Alhamdulillah" (praise be to Allah) at the end; never criticizing food; sometimes praising food; conversing while eating; repeatedly offering food to guests; supplicating for the household; commanding eating with the right hand and forbidding eating with the left; commanding gathering together for food and mentioning Allah's name over it for blessings; not eating while reclining; and eating with three fingers.

From his guidance regarding moderation: knowing what one eats, eating what is beneficial, and being moderate in eating to sustain the body, not to accumulate fat. He (peace and blessings be upon him) said: "Indeed, a believer eats in one intestine, and a disbeliever eats in seven intestines." He also said: "No human ever filled a vessel worse than the stomach. Sufficient for the son of Adam are a few morsels to keep his back straight. But if he must needs fill it, then a third for his food, a third for his drink, and a third for his breath."