IELTS Academic Reading # 150 - The Search for the Anti-aging Pill

You should spend about 20 minutes on Questions 28-40, which are based on the Reading Passage below.

The Search for the Anti-aging Pill

In government laboratories and elsewhere, scientists are seeking a drug able to prolong
life and youthful vigor. Studies of caloric restriction are showing the way

As researchers on aging noted recently, no treatment on the market today has been proved to slow human aging- the build-up of molecular and cellular damage that increases vulnerability to infirmity as we grow older. But one intervention, consumption of a low-calorie* yet nutritionally balanced diet, works incredibly well in a broad range of animals, increasing longevity and prolonging good health. Those findings suggest that caloric restriction could delay aging and increase longevity in humans, too.

Unfortunately, for maximum benefit, people would probably have to reduce their caloric intake by roughly thirty per cent, equivalent to dropping from 2,500 calories a day to 1, 750. Few mortals could stick to chat harsh a regimen, especially for years on end. But what if someone could create a pill that mimicked the physiological effects of eating less without actually forcing people to eat less? Could such a 'caloric-restriction mimetic', as we call it, enable people to stay healthy longer, postponing age-related disorders (such as diabetes, arteriosclerosis, heart disease and cancer) until very lace in life? Scientists first posed this question in the mid-1990s, after researchers came upon a chemical agent that in rodents seemed to reproduce many of caloric restriction's benefits. No compound that would safely achieve the same feat in people has been found yet, but the search has been informative and has fanned hope that caloric-restriction (CR) mimetics can indeed be developed eventually.

The benefits of caloric restriction
The hunt for CR mimetics grew out of a desire to better understand caloric restriction's many effects on the body. Scientists first recognized the value of the practice more than 60 years ago, when they found that rats fed a low-calorie diet lived longer on average than free-feeding rats and also had a reduced incidence of conditions that become increasingly common in old age. What is more, some of the treated animals survived longer than the oldest-living animals in the control group, which means that the maximum lifespan (the oldest attainable age), not merely the normal lifespan, increased. Various interventions, such as infection-fighting drugs, can increase a population's average survival time, but only approaches chat slow the body's rate of aging will increase the maximum lifespan.

The rat findings have been replicated many times and extended to creatures ranging from yeast to fruit flies, worms, fish, spiders, mice and hamsters. Until fairly recently, the studies were limited short-lived creatures genetically distant from humans. But caloric-restriction projects underway in two species more closely related to humans- rhesus and squirrel monkeys- have scientists optimistic that CR mimetics could help people.

* calorie: a measure of the energy value of food.

The monkey projects demonstrate that compared with control animals that eat normally. caloric-restricted monkeys have lower body temperatures and levels of the pancreatic hormone insulin, and they retain more youthful levels of certain hormones that tend to fall with age.

The caloric-restricted animals also look better on indicators of risk for age-related diseases. For example, they have lower blood pressure and triglyceride levels(signifying a decreased likelihood of heart disease) and they have more normal blood glucose levels( pointing to a reduced risk for diabetes, which is marked by unusually high blood glucose levels). Further, it has recently been shown that rhesus monkeys kept on caloric-restricted diets for an extended time( nearly 15 years) have less chronic disease. They and the other monkeys must be followed still longer, however, to know whether low-calorie intake can increase both average and maximum lifespans in monkeys. Unlike the multitude of elixirs being touted as the latest anti-aging cure, CR mimetics would alter fundamental processes that underlie aging. We aim to develop compounds that fool cells into activating maintenance and repair.

How a prototype caloric-restriction mimetic works
The best-studied candidate for a caloric-restriction mimetic, 2DG (2-deoxy-D-glucose), works by interfering with the way cells process glucose, it has proved toxic at some doses in animals and so cannot be used in humans. But it has demonstrated that chemicals can replicate the effects of caloric restriction; the trick is finding the right one.

Cells use the glucose from food to generate ATP (adenosine triphosphate), the molecule that powers many activities in the body. By limiting food intake, caloric restriction minimizes the amount of glucose entering cells and decreases ATP generation. When 2DG is administered to animals that eat normally, glucose reaches cells in abundance but the drug prevents most of it from being processed and thus reduces ATP synthesis. Researchers have proposed several explanations for why interruption of glucose processing and ATP production might retard aging. One possibility relates to the ATP-making machinery's emission of free radicals, which are thought to contribute to aging and t such age-related diseases as cancer by damaging cells. Reduced operation of the machinery should limit their production and thereby constrain the damage. Another hypothesis suggests that decreased processing of glucose could indicate to cells that food is scarce( even if it isn't) and induce them to shift into an anti-aging mode that emphasizes preservation of the organism over such 'luxuries' as growth and reproduction.

Questions 28-32:
Do the following statements agree with the claims of the writer in the Reading Passage?

In boxes 28-32 on your answer sheet, write

    YES if the statement t agrees with the claims of the writer
    NO if the statement contradicts the claims of the writer
    NOT GIVEN if it is impossible to say what the writer thinks about this

28. Studies show drugs available today can delay the process of growing old.
29. There is scientific evidence that eating fewer calories may extend human life.
30. Not many people are likely to find a caloric-restricted diet attractive.
31. Diet-related diseases are common in older people.
32. In experiments, rats who ale what they wanted to lead shorter lives than rats on a low calorie diet.

Questions 33-37:
Classify the following descriptions as relating to

A  caloric-restricted mimetic
control monkeys
C  neither caloric-restricted monkeys nor control monkeys

Write the correct letter, A, B or C, in boxes 33-37 on your answer sheet.

33. Monkeys were less likely to become diabetic.
34. Monkeys experienced more chronic disease.
35. Monkeys have been shown to experience a longer than average life span.
36. Monkeys enjoyed a reduced chance of heart disease.
37. Monkeys produced greater quantities of insulin.

Questions 38-40:
Complete the flowchart below.
Choose NO MORE THAN TWO WORDS from the passage for each answer.
Write your answers in boxes 38-40 on your answer sheet.

          How a caloric-restriction mimetic works

Reading 150

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1 1 1 1 1 1 1 1 1 1 Rating 3.54 (14 Votes)

I think the answer to question 32 should be 'yes'.
Can someone explain the answer to question 30 here??? Thanks in advance.
29 answer.
Thank you, but there is not "evidence", only "suggestion" for human )), which "could ...", that is completely not an evidence.
I don't think this is gonna be possible of reducing or finishing the age difference. No one can stop it but the death. Here the question arises why someone wants to live longer in this world which they consider to be cruel and mean. So stop worrying about aging. Just live the moments you have with dignity pleasure. I have seen many people wanting to die soon and have assisted suicide to get rid of the life they don't want to live further...
I agree with Amir that the script doesn't mention scientific evidence of life extension among humans. In fact, the last statement of paragraph 2 mentions otherwise. The answer to question 29 should have been 'NO'. Whereas for statement 30, paragraph 2nd mentions 'Few mortals could stick to a harsh regime, especially for many years', it doesn't talk about the liking and disliking of the mortals. In my opinion, the answer should have been 'Not Given'. Also for question 31, can anyone help me understand where is such statement contradicted for the answer to be 'No'?
The answer to the question 32 is 'YES'.
You are right. The answer to the question 32 is yes.
Gurjeet Kapoor
Yea no. 32 is 'yes'.
Gurjeet Kapoor
There is a shuffle between 31 and 32 answers. Further clarification would be highly appreciated!!
The answer to the question 29 should be 'Yes'. It cannot be 'NO' because the information does not contradict human beings! It comprises of both animals and humans. They asked for humans and it is mentioned in the favour of humans. It would be 'NO' if they had asked for animals/humans only. It is a tricky one.
The answer to the question 32 should be "Yes". The statement: "they found that rats fed a low-calorie diet lived longer on average than free-feeding rats". The question: "rats who ate what they wanted to lead shorter lives than rats on a low-calorie diet."
The answer to the question 29 should be "No". There's scientific evidence on animal life, but not on human life, and that's the reason the statement says "suggest" and "could" in "Those findings suggest that caloric restriction could delay ageing and increase longevity in humans, too."
I have confusion about the answers. Some of the answers do not look suitable. Could you please explain answers how they work? Regards-
Please clarify the answer to the question 32.
Thanks for this marvellous post! I quite enjoyed reading it. The IELTS Reading section is a bit tougher than other parts and the reading samples with answers provided here are very helpful for me.