Diet pills have become increasingly popular during the past decade. Used both by people who only want to get rid of a couple of pounds, and by those who'd rather get a dramatic, life-changing weight loss, diet pills are still a mystery to many of us.

Do diet weight loss pills really work? And if so, are they safe? How can you tell if a certain diet pill will provide the expected results? And do you need medical prescription in order to follow a weight loss regimen with diet pills?

These are only some of the most important questions regarding weight loss pills. If you've decided to give them a shot, take a look at the following list of safe weight loss pills that work - both safe over the counter weight loss pills and safe prescription weight loss pills.

Safe Diet Pill

Safe Diet Pills: Alli

Alli is an over the counter weight loss pill that has a lower dosage of orlistat, the main ingredient of the more popular diet pill Xenical. It is approved by the FDA and works by preventing the digestion of roughly 25% of the fat ingested through eating. In numbers, Alli is a diet pill that may help you decrease the amount of calories ingested daily by 100-200 calories.

Alli is usually recommended to overweight and obese people (with a BMI of at least 25), but not to those who only want to shed a couple of pounds for bikini season. The main reasons are the side effects: oily, loose stools after a greasy meal, and vitamin loss.

Safe Diet Pills: Xenical

Xenical is the prescription variant of Alli, as it contains a higher dose of orlistat. It is a lipase inhibitor, just as Alli, blocking the absorption of a variable quantity of ingested fat.

Xenical is usually prescribed along with a low calorie diet, and it leads to an increase of 5% to 10% in weight loss, compared to people following a low calorie diet, but not taking Xenical. Like Alli, this diet pill is recommended to overweight and obese people wanting to lose a significant amount of weight, and it has similar side effects (oily stool, oily discharges, numerous bowel movements).

Weight Loss Pills

Safe Diet Pills: CLA

CLA or Conjugated Linoleic Acid is actually a diet supplement that aids in weight loss, having other multiple health benefits. In spite of being a fatty acid, which may sound counterintuitive when it comes to losing weight, CLA has been proved to be effective in reducing the amount of body fat. Still, its usage should be limited, as some studies have shown that CLA may lead to higher cholesterol levels and body inflammation.

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