To combat steroid use and in the hopes of becoming a member of the IOC, the IFBB introduced doping tests for both steroids and other banned substances. Although doping tests occurred, the majority of professional bodybuilders still used anabolic steroids for competition. During the 1970s, the use of anabolic steroids was openly discussed, partly due to the fact they were legal.[9] In the Anabolic Steroid Control Act of 1990, U.S. Congress placed anabolic steroids into Schedule III of the Controlled Substances Act (CSA). In Canada, steroids are listed under Schedule IV of the Controlled Drugs and Substances Act, enacted by the federal Parliament in 1996.[10]

Gastrointestinal disorders are another common cause of unexplained weight loss – in fact they are the most common non-cancerous cause of idiopathic weight loss.[citation needed] Possible gastrointestinal etiologies of unexplained weight loss include: celiac disease, peptic ulcer disease, inflammatory bowel disease (crohn's disease and ulcerative colitis), pancreatitis, gastritis, diarrhea and many other GI conditions.

Some Bodybuilders often split their food intake into 5 to 7 meals of equal nutritional content and eat at regular intervals (e.g. every 2 to 3 hours). This approach serves two purposes: to limit overindulging in the cutting phase, and to allow for the consumption of large volumes of food during the bulking phase. Eating more frequently does not increase basal metabolic rate when compared to 3 meals a day.[38] While food does have a metabolic cost to digest, absorb, and store, called the thermic effect of food, it depends on the quantity and type of food, not how the food is spread across the meals of the day. Well-controlled studies using whole-body calorimetry and doubly labeled water have demonstrated that there is no metabolic advantage to eating more frequently.[39][40][41]
The important role of nutrition in building muscle and losing fat means bodybuilders may consume a wide variety of dietary supplements.[42] Various products are used in an attempt to augment muscle size, increase the rate of fat loss, improve joint health, increase natural testosterone production, enhance training performance and prevent potential nutrient deficiencies.
Unintentional weight loss may result from loss of body fats, loss of body fluids, muscle atrophy, or even a combination of these.[25][26] It is generally regarded as a medical problem when at least 10% of a person's body weight has been lost in six months[25][27] or 5% in the last month.[28] Another criterion used for assessing weight that is too low is the body mass index (BMI).[29] However, even lesser amounts of weight loss can be a cause for serious concern in a frail elderly person.[30]
The great positive impact of public health programs is widely acknowledged. Due in part to the policies and actions developed through public health, the 20th century registered a decrease in the mortality rates for infants and children and a continual increase in life expectancy in most parts of the world. For example, it is estimated that life expectancy has increased for Americans by thirty years since 1900,[55] and worldwide by six years since 1990.[56]