[单项选择]New research from Australia supports the belief that many pet owners have—it shows that pets are good for your health. The 1 of this new study suggest that people who have pets are 2 less risk from heart disease than 3 who do not. Ironically this 4 study on pets was intended to 5 the myth that pets are good for your health. Earlier research 6 the benefits of owning pets received a lot of 7 , but the results were not good enough to 8 the more skeptical doctors. The new research was carried 9 over three years and examined 6000 people, the largest group yet involved in 10 a study. They took tests that measured a 11 of different factors known to be 12 in heart disease— 13 and blood levels of cholesterol (胆固醇) and triglyceride (甘油三酸酯). 14 , people were asked about their lifestyles. The 800 people who owned pets had 15 levels on each of the factors 16 than those who did not own pets. The differences were even greater than those found in similar studies on people who 17 to vegetarian diets or took 18 exercise. The study also showed that it did not matter 19 kind of pet was owned—a cat was as good as a dog—so the benefits could not be attributed 20 the exercise involved in walking a dog.
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