Americans eat so much they think overeating is normal. Bariatric patients (morbidly obese people getting their stomach essentially amputated, see Roux-en-Y) are generally told to fast for 24 hours prior to surgery. Their glucose levels before surgery are often normal, for the first time in decades.

The association between food intake and obesity is far, far stronger than cigarettes and lung cancer, even stronger than Hep B and hepatocellular carcinoma.

Asserting that eating less (and I do mean significantly less) needs to be studied more is like saying we should hold off on parachute use until more studies are done.