Restricting food intake over a long period

 

Restricting food intake over a long period during a person's teenage years can stunt growth. Following restrictive diets over a long period can also delay some of the changes associated with puberty, such as breast development in females and muscle bulk in males. Another side effect of restrictive diets in teenage girls is irregular menstrual periods - or even not getting a period at all.
Another effect of very low-calorie diets is a decrease in resting energy expenditure, or the amount of calories a person burns at rest. One reason for this "slower metabolism" is that people on restrictive diets often lose muscle mass, and muscle burns more calories than fat - even while a person is resting. This makes continuing to lose weight even more difficult and regaining weight easier.
What about the long-term effects of taking diet pills? Common ingredients in diet pills include caffeine, alcohol, 5-hydroxytryptophan (5-HTP), chromium (or chromium picolinate), phentermine, and vanadium. These ingredients may carry health risks for certain people. Ephedrine (also known as ephedra or ma huang), an ingredient in many diet and sports supplements during the late 1990s and early 2000s, was linked to heart problems and may have played a role in the death of at least one professional athlete. The U.S. Food and Drug Administration decided the health risks associated with ephedra were too great, and it banned the substance in December 2003.
If you have any health conditions or are taking medication, always check with your doctor before taking weight-loss supplements because the ingredients in some supplements may interact with specific drugs. For example, 5-HTP may cause adverse reactions in people who take certain medications for depression.
Even ingredients that seem like a normal part of your diet can carry risks when used in weight-loss pills or other stimulants: For example, the average caffeine-based weight-loss pill contains as much caffeine as 6 cups of coffee. Imagine how wired you'd be if you took two or three of these pills each day! The side effects associated with these products include rapid heart rate, increased blood pressure, dizziness, sleeplessness, seizures, and even addiction.
Furthermore, it's important to know that most diet supplements have not been tested on teen users. Not only does this mean that the dosages prescribed may not be accurate, it could mean that taking certain supplements might carry unknown risks for teens.