The general consensus on diet pills are contained in two powerful words: BUYER BEWARE.
The problem here is that many makers of diet pills offer claims that simply aren't realistic; and if you read the fine-print of most of these advertisements, you'll see that they're really too good to be true. Little notes like the claims made in this advertisement are not typical should be enough of a wake-up call to realize that there's more to the story.
In some cases, diet pills can help boost metabolism temporarily. This, however, can be risky and generally shouldn't be done without a doctor's say-so. Unfortunately, people can become somewhat addicted to diet pills, and this can lead to disaster.
And before we go onto myth #2, remember that some diet pills are water loss pills. That is, they are diuretics that promote water loss, usually through excess urination. The jury on water-loss diet pills is somewhat less open-minded than diet pills in general: THEY DON'T WORK!
Seriously: water loss diet pills are built on the premise that you'll lose weight through water. And, yes, that's true: if you urinate 15 times a day, you're physically going to weigh less.
But this is not actual weight loss! This is merely unhealthy temporary weight loss, and it will come roaring back the minute that water stores are replenished through diet.
Or, even harder to comprehend, if a person taking these water pills fails to restore their body's fluid needs, they can actually suffer dehydration; which can, and has, led to coma and death.