Unfortunately, weight loss diets don't work very well, and that's one of the reasons why there is always a diet book on the best-seller list.

很不幸,食品减肥的作用不明显,正因为如此,最畅销书榜才总有减肥食品的书上榜

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

And as I will explain in a second there are many reasons why this sense hasn't really been elucidated at the molecular level.

难以真正从分子学的角度阐明,这种感官的原因是多方面的,有关这一点,稍后我会另行解释。

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