Monell Chemical Senses Center, Philadelphia, Pennsylvania, USA.
Prog Mol Biol Transl Sci. 2010;94:213-40. doi: 10.1016/B978-0-12-375003-7.00008-X.
Eating is dangerous. While food contains nutrients and calories that animals need to produce heat and energy, it may also contain harmful parasites, bacteria, or chemicals. To guide food selection, the senses of taste and smell have evolved to alert us to the bitter taste of poisons and the sour taste and off-putting smell of spoiled foods. These sensory systems help people and animals to eat defensively, and they provide the brake that helps them avoid ingesting foods that are harmful. But choices about which foods to eat are motivated by more than avoiding the bad; they are also motivated by seeking the good, such as fat and sugar. However, just as not everyone is equally capable of sensing toxins in food, not everyone is equally enthusiastic about consuming high-fat, high-sugar foods. Genetic studies in humans and experimental animals strongly suggest that the liking of sugar and fat is influenced by genotype; likewise, the abilities to detect bitterness and the malodors of rotting food are highly variable among individuals. Understanding the exact genes and genetic differences that affect food intake may provide important clues in obesity treatment by allowing caregivers to tailor dietary recommendations to the chemosensory landscape of each person.
进食是有风险的。食物中既含有动物维持体温和产生能量所需的营养物质和卡路里，也可能含有有害的寄生虫、细菌或化学物质。为了指导食物选择，味觉和嗅觉已经进化到可以提醒我们注意毒物的苦味和变质食物的酸味和难闻气味。这些感官系统帮助人和动物进行有防御性的进食，为避免摄入有害食物提供了刹车作用。但是，选择吃哪种食物不仅仅是为了避免吃坏的食物，还受到寻找好的食物的动机的驱动，如脂肪和糖。然而，正如并非每个人都同样能够感知食物中的毒素一样，也并非每个人都同样热衷于食用高脂肪、高糖的食物。人类和实验动物的遗传研究强烈表明，对糖和脂肪的喜爱受到基因型的影响；同样，对苦味的感知能力和对腐臭食物的恶臭气味的感知能力在个体之间差异很大。了解影响食物摄入的确切基因和遗传差异，可能通过允许护理人员根据每个人的化学感官环境来调整饮食建议，从而为肥胖症治疗提供重要线索。
