Dietary habits are a complex amalgam of personal preference, ingrained custom, and societal influences. The modification of behaviors in relation to the pattern of food consumption is an intricate process, as these diverse factors are not readily addressed with one dietary tactic or approach.
Diet is both the summary of the foods consumed by an individual, as well as the actual or predicted schedule of such consumption. When constructed in advance of any ingestion of food, the diet is a planning and organizational tool: athletes, persons with restrictions regarding food allergies or medication, or persons endeavoring to either gain or to lose weight employ diet in this fashion. When used as a review of precisely what a person may have consumed over a designated period, a diet is an analytical device, where past consumption can be compared to physical or performance changes noted in the body.
For these reasons, diet is a powerful tool for the modification of behavior. The most common desired form of behavior modification in relation to food is the curbing of overeating and resultant obesity. The most straightforward method of weight reduction is based upon simple physics—if human caloric output exceeds caloric intake (where activity/exercise energy demands are greater than the food energy consumed), the human body will lose mass, because it must convert mass into energy.
As with many simple, direct solutions, diet quantity restrictions alone have proven to be generally unsuccessful in controlling excess weight, especially over an indefinite period. A simple diet that proposes to reduce 500 calories per day will not succeed in a vacuum; the societal pressure to eat, as evidenced by the appearance of mass-marketed and sometimes unhealthy food choices, makes the maintenance of the required willpower to unilaterally cut back on food consumption a very difficult task for many people. Further, even those persons who have previously reduced weight in this fashion often discover their eating habits to have been only temporarily modified. This incomplete behavioral change often results in a "yo-yo" dieting scenario, where excess body mass is gained and lost on a number of occasions. A yo-yo weight gain and weight loss places significant additional stresses on the musculoskeletal structure.
Initiatives to build a better diet must be supported by one or more additional behavior modifiers. These include exercising, maintaining a food diary, creating a list of foods to avoid, and counting calories.
Exercise is key, especially those activities that require elements of endurance exercise, in increments of at least 30 minutes per day, four times per week. Endurance exercise, which utilizes the aerobic energy system to power the body during the activity, tends to have both higher energy requirements as well as providing a metabolic "afterglow," where the body will experience an increase in its resting metabolic rate, meaning more energy will be consumed at rest.
Within a food diary, individuals record the types and quantities of food consumed. These records serve to reinforce good dietary habits as well as provide a reference point on a review of the diet progress. Also, it can help individuals identify foods that stimulate excess appetite so that they can avoid them.
Finally, it is important to count the calories both anticipated in a scheduled diet, as well as those actually consumed. Most national food guides and other nutritional sources provide accurate information as to the caloric value of foods, by portion size.
The principles of behavior modification in relation to diet apply to all persons seeking a definable physical result in the performance of their bodies. Athletes who are outwardly very lean and fit, especially in aerobic sports where the body's energy is derived from the consumption of carbohydrates, can fall into poor dietary practices and not be aware of certain vitamin and mineral deficits based on their weight or body shape alone. For the athlete, it is sluggish performance, or a corresponding desire to improve performance, that will provide incentive to modify dietary behavior.
Athletes and less active people also share the temptation to seek out a quick fix to their dietary concerns, often in the form of a supplement. For the athlete, the supplement may be vitamins, minerals, or weight-gaining, protein-type additives such as creatine. For the weight-loss person, there are numerous so-called diet or weight-loss formulas. Research into the efficacy of weight-loss formulas confirms that a broad-based modification of diet behavior is a far better long-term solution, as the modification is being made with the body's well understood and natural mechanism, food.
Appetite suppressants are sometimes employed by people who wish to lose weight on a long-term basis, as well as athletes such as boxers and jockeys, who must intermittently qualify for competition in a specific weight category. Such suppressants, which are often significant amounts of caffeine or other stimulants, are the antithesis of a modified behavior, representing an ultimately short-term solution to an ongoing dietary problem.