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1、Let’sgoveggie!HumanNutrition:Humanbeingsrequirefoodtogrow,reproduce,andmaintaingoodhealth.Withoutfood,ourbodiescouldnotstaywarm,buildorrepairtissue,ormaintainaheartbeat.Eatingtherightfoodscanhelpusavoidcertaindiseasesorrecoverfasterwhenillnessoccurs.Theseandotherimportant
2、functionsarefueledbychemicalsubstancesinourfoodcallednutrients.Nutrientsareclassifiedascarbohydrates,proteins,fats,vitamins,minerals,andwater.Whenweeatameal,nutrientsarereleasedfromfoodthroughdigestion.Digestionbeginsinthemouthbytheactionofchewingandthechemicalactivityofs
3、aliva,awateryfluidthatcontainsenzymes,certainproteinsthathelpbreakdownfood.Furtherdigestionoccursasfoodtravelsthroughthestomachandthesmallintestine,wheredigestiveenzymesandacidsliquefyfoodandmusclecontractionspushitalongthedigestivetract.Nutrientsareabsorbedfromtheinsideo
4、fthesmallintestineintothebloodstreamandcarriedtothesitesinthebodywheretheyareneeded.Atthesesites,severalchemicalreactionsoccurthatensurethegrowthandfunctionofbodytissues.Thepartsoffoodsthatarenotabsorbedcontinuetomovedowntheintestinaltractandareeliminatedfromthebodyasfece
5、s.人类需要的食物，生长，繁殖，保持身体健康。没有食物，我们的身体无法保暖，建设或修复组织，或维持心跳。吃正确的食物可以帮助我们避免某些疾病或疾病发生时，恢复更快。这些和其他重要的功能是加剧了在我们的食物称为营养素的化学物质。养分被列为碳水化合物，蛋白质，脂肪，维生素，矿物质和水。 当我们吃个饭，营养物质被释放出来，通过消化食物。开始由消化咀嚼行动和唾液，水样液体，含有酵素，可帮助分解食物中的某些蛋白质的化学活性的嘴。进一步消化食物时，通过胃和小肠，消化酶和氨基酸的食物和肌肉收缩液化推动它沿着消化道传播。养分的吸收从小肠进入
6、血液，并进行内部在需要它们的地方机构的网站。在这些网站，一些化学反应发生，确保增长和身体组织的功能。那未被吸收继续向下移动肠道，并从粪便排出体外，作为食品的部分。Vegetarianismandhealth:Peoplehaveadoptedvegetariandietsbasedonscientificstudiesshowingthatdietshighinfattyanimalfoodsmaycontributetotheearlydevelopmentofdisease,includingobesity,coronaryarter
7、ydisease,highbloodpressure,diabetesmellitus,andcolorectalcancer.TheUnitedStatesSurgeonGeneral’s1988reportonnutritionandhealthurgedAmericanstoreducetheirintakesofanimalfats,suchasthosefoundinmeatanddairyproducts,andtoincreaseconsumptionoffruits,vegetables,andwholegrains.Th
8、evegetarianplant-baseddiettypicallyhastheadvantageofbeinglowinsaturatedfat,cholesterol,andsalt,b
