Background

"Mass Gainer" is a term referring to substances that have been used with the intention of gaining muscle mass. Some of these substances include anabolic androgenic steroids, andro supplements, creatine, stimulants, diuretics, and protein.

Anabolic androgenic steroids are synthetic forms of the hormone testosterone that can be used to help gain muscle mass. "Anabolic" refers to muscle-building, "androgenic" refers to increased masculine characteristics, and "steroids" refers to the class of drugs. Anabolic androgenic steroids are legally available only by prescription, to treat conditions that occur when the body produces abnormally low amounts of testosterone, such as delayed puberty and some types of impotence. They are also prescribed to treat body wasting in AIDS patients, for weight gain after serious illnesses (such as anemia or cancer) and other diseases that result in loss of lean muscle mass. Abuse of anabolic steroids, however, can lead to serious and even irreversible health problems. Many people use illegal steroids to enhance muscle mass and improve physical performance.

Andro supplements are dietary supplements that are steroid-like or are related to steroids. Andro supplements include: androstenedione, androstenediol, norandrostenedione, norandrostenediol, and dehydroepiandtrosterone. In 2004, the U.S. Food and Drug Administration (FDA) declared andro supplements illegal, due to safety concerns.

Other supplements used as mass gainers include: creatine monohydrate, HMB (beta-hydroxy beta-methylbutyric acid), caffeine, ephedra (which is currently illegal), diuretics, and protein.

Effectiveness Effectiveness definitions

Mass gainers represent a wide group of substances. See specific substances for effectiveness information.

Natural Medicines rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

Dosing & administration

Adverse effects

General: Adverse Effects: Mass gainers represent a wide group of substances. See specific substances for adverse effects information.

Interactions with pharmaceuticals

None known.

Interactions with herbs & supplements

Mass gainers represent a wide group of substances. See specific substances for interactions information.

Interactions with foods

Mass gainers represent a wide group of substances. See specific substances for interactions information.

Interactions with lab tests

Mass gainers represent a wide group of substances. See specific substances for interactions information.

Interactions with diseases

Mass gainers represent a wide group of substances. See specific substances for interactions information.

Mechanism of action

Mass gainers represent a wide group of substances. See specific substances for further mechanism information.

Vendors of andro supplements claim the supplements convert into testosterone in the body and help improve muscle mass. Andro acts like a steroid once it is metabolized by the body and therefore can pose similar kinds of health risks as steroids.

Creatine monohydrate, found in protein-rich foods like meat or fish, is used as a mass gainer because it theoretically increases the amount of energy available to muscles and prevents lactic acid build-up. DHEA has been marketed for increasing muscle tissue growth. HMB has been theorized to help with exercise performance by decreasing muscle breakdown.