PrepTest 146, Section 2, Question 15
Nutritionist: Most fad diets prescribe a single narrow(47 more words not shown)
Which one of the following(8 more words not shown)
- AMost fad diets(11 more words not shown)
- BFruits and vegetables(18 more words not shown)
- CAny two people(9 more words not shown)
- DMost fad diets(9 more words not shown)
- EThere are very(15 more words not shown)
Reading the argument
One narrow prescription for everyone sounds questionable when people's nutritional needs differ. The nutritionist also gives us a recommendation that does apply to everyone: eat plenty of fruits and vegetables.
What we’re looking for
A fad diet that leaves those out would conflict with that recommendation. But do these fad diets all leave them out? We aren't told. A restrictive plan could include fruits and vegetables, so we shouldn't decide the answer by inventing its menu. We need to follow what the nutritionist actually says about the range of nutrients and the range of people's needs. For the most-supported question, I'd expect some limit on how well these diets serve everyone, or a conclusion reflecting the shared recommendation. Let's see which claim the facts support.
Working the answers
- A
The nutritionist recommends plenty of fruits and vegetables for everyone. That doesn't mean most fad diets make the same recommendation. We know they prescribe a narrow range of nutrients, but we don't know what foods they include. A substitutes the nutritionist's advice for the diets' actual rules.
- B
Fruits and vegetables protect against many health problems. The passage doesn't say they are the only foods with nutrients that provide broad protection. Another kind of food could also help with several problems without conflicting with anything the nutritionist says.
- C
Needs vary widely across people; that doesn't mean every pair of people has different needs. Two people might need much the same diet. Saying people have different blood types, for example, doesn't mean every individual has a unique blood type. C turns variation within a population into a claim that no two individuals are alike.
- DCorrect
Connect the first two claims. Most fad diets give everyone the same narrow range of nutrients, while people's dietary needs vary widely. A fixed narrow prescription will fail to meet the needs of some of those different people. Imagine someone who needs more protein or vitamin D than the plan provides. The same prescription might suit another person while leaving this person's needs unmet.
We don't have to show that the diets exclude fruits and vegetables to get this result. The problem is their failure to accommodate differing needs. And D keeps its scope limited: most fad diets fail some people. It doesn't say every fad diet fails everyone.
- E
We have no inventory of which nutrients occur in all foods other than fruits and vegetables. The passage concerns how diets meet people's needs, not whether the many other foods share very few nutrients. E introduces a distribution claim the nutritionist never provides.
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