1、单元背景阅读The top five super foods at handAll foods have some nutritional value. But there are five at hand that are so beneficial to your health they are known as “super foods”.1. Apples Apples are full of vitamin C for healthy skin and gums one apple provides a quarter of your daily requirement of vit
2、amin C. Apples also contain a form of soluble (可溶的) fibre called pectin (胶质) that can help to lower blood cholesterol (胆固醇) levels and keep the digestive system healthy. An apple is also a carbohydrate (碳水化和物) with a low glycaemic index (GI) type. They may help with weight control, as well as improv
3、ing diabetics (糖尿病患者) long-term control of blood sugar levels.2. Baked beans The baked bean is a nutritional powerhouse of protein, fibre, iron and calcium. It contains carbohydrate that, like that in apples, is of the low GI variety. The insoluble fibre in baked beans is not digested but moves into
4、 the large intestine (肠), where bacteria (细菌) act on it and produce short-chain fatty acids (脂肪酸) which are thought to nourish the colon lining and protect it from cancer-causing invaders (侵略者). 3. Salmon (鲑鱼) All fish is a source of good-quality protein, vitamins and minerals, but salmon contains o
5、mega 3 fats that reduce blood clotting (凝结) and inflammation (肿痛发炎). It rescues the risk of having a heart attack, even in older adults. Omega 3 fats also help to prevent depression, and protect against the onset of dementia (痴呆). Its true that fish really is an all-round brain food. 4. Tea The drin
6、k is helpful for stimulating alertness (机警), mood and motivation. Tea counts towards eight cups daily to avoid dehydration (脱水). Tea, whether black or green, is a rich source of the antioxidant (抗氧化剂) called catechins (儿茶酚) that protect the artery (动脉) walls against the damage that causes heart dise
7、ase and prevents formation of sticky blood clots. 5. Bananas Its a myth that bananas are fattening. Bananas are slightly higher in energy than other fruits and are excellent for refuelling before, during or after exercise. Bananas are also jam-packed with potassium (钾) that helps lower blood pressure, and vitamin B6 for healthy skin and hair.
