The secret to eating less and being happy about it may have been uncovered years ago — by McDonald’s. According to a new study from Cornell University’s Food and Brand Lab,     1     non-food rewards — like the toys in McDonald’s Happy Meals — stimulate the same reward centers in the brain as food does.

The researchers, led by Martin Reimann, carried out a series of experiments to see if people would choose a smaller meal if it was     2     together with a non-food item.

They found that the majority of both kids and adults chose a half-sized portion (部分) when combined with a prize. Both options were     3     the same.

Even more interesting is that the     4     of a future reward was enough to make adults choose the smaller portion. One of the prizes used was a lottery ticket (彩票), with a $10, $50 or $100 payout, and this was as effective as a tangible (有形的) gift in persuading people to eat less.

The fact that participants were willing to     5     part of a food item for the mere prospect of a relatively small monetary award is interesting,” says Reimann.

He theorizes that it is the     6     component of these intangible prizes that make them effective. In fact, vaguely-stated (含糊的) possibilities of winning a prize were more effective than options with hard odds (可能性) included.

“One explanation for this finding is that possible awards may be more emotionally exciting than certainty awards,” says Reimann. “The uncertainty of winning provides added     7     and desirability through emotional ‘thrills.’ The possibility of receiving an award also produces a state of hope — a state that is in itself     8     rewarding.” In other words, there’s a reason why people like to gamble (赌博).

How might this knowledge be used to help people eat more healthily?

One possibility is a healthy choice that     9     the chance to win a spa weekend. Or maybe the reward of a half-sized portion that could be a half-sized dessert to be     10     only on a future date. That would get you back in the restaurant — and make you eat a little less.