There are various tricks that can be used to get around the basic ideas of calorie balance. The key is to somehow cheat, either reducing calorie intake, suppressing appetite, or speeding up metabolism.
- Fat blocker: A chemical that is ingested along with food. It binds to fat, making it undigestible. Aside from causing greasy stools, it also binds to fat-soluble vitamins, as well as essential fatty acids such as omega-3. Over time, this can cause vitamin defficiencies, which aren't noticed immediately, as the body has a store of these vitamins in body fat.
- Undigestibles: Substances that occupy space in the stomach, without actually providing any calories. Olean (Wow! chips) falls into this category. Some are merely slow-digestibles, such as cellulose gum or gel, as found in Slim-fast and many frozen low-calorie dinners. They cause appetites to be temporarily suppressed; however, the body determines appetite by calories consumed, so usually the response is to eat more of these foods. Fighting this urge is difficult.
- Speed-derivatives: Drugs you take to reduce appetite, such as Dexetrim or methamphetamine. See also The E-Plan diet. These also speed up the metabolic process, causing more calories to be burned at rest. This approach really does work, but has some major side-effects. These drugs are addictive, have overdose potential, and eventually have a reduced effect. Ironically, later stages of speed withdrawal also bring about increased appetite, so going off these drugs usually involves putting weight right back on.