| The following appeared in the health section of a magazine on trends and lifestyles.
“People who use the artificial sweetener aspartame are better off consuming sugar, since aspartame can actually contribute to weight gain rather than weight loss. For example, high levels of aspartame have been shown to trigger a craving for food by depleting the brain of a chemical that registers satiety, or the sense of being full. Furthermore, studies suggest that sugars, if consumed after at least 45 minutes of continuous exercise, actually enhance the body’s ability to burn fat. Consequently, those who drink aspartame-sweetened juices after exercise will also lose this calorie-burning benefit. Thus it appears that people consuming aspartame rather than sugar are unlikely to achieve their dietary goals.”
Discuss how well reasoned... etc.
The author here is recommending people who use the artificial sweetener aspartame to switch to sugar to achieve their dietary goals. To make the argument persuasive, the author demonstrates two reasons for the advocacy. First, high levels of aspartame can stimulate people to eat more. Second, sugar can burn fat under a certain condition where aspartame can not. However, the line of reasoning in this argument is awkward since it cites inappropriate examples and is based on gratuitous assumptions.
To begin with, the argument cites an example in which high levels of aspartame result in eating more food. However, people who use aspartame do not necessarily have high levels of aspartame. It is unreasonable to assume that people will consume so large volume of aspartame to lose weight that negative effect results. The specific example is not applicable to all conditions and the author doesn’t give the disadvantages of aspartame under usual conditions.
Furthermore, the argument cites a fact that sugar can sometimes burn fat to consolidate its conclusion that aspartame is not that effecive as expected. Unfortunately, the example is not appropriate as it requires 45 minutes of continuous exercise to make sugar burn fat. Without comparing sugar and aspartame under other conditions, it is not sufficient for the argument to reach the conclusion. For instance, how if aspartame is generally more effective in burning fat and the example cited is the only exception.
Suffering from those flaws, the argument is not quite convincing and sound. The two reasons given by the author are not reliable to suggest all dieters to discard aspartame and switch to sugar. To strengthen the argument, the author has better cite more appropriate examples which are applicable to all conditions, or demonstrate other advantages of sugar compared with aspartame..
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