Satiety and Appetite Control

Definition

Satiety is the feeling of fullness and the suppression of hunger for a period of time after a meal. Feelings of satiety can influence appetite and when and how much is eaten next. Appetite controls are an important aspect of maintaining a healthy weight.

Purpose

Satiety is a vital psycho-biological mechanism whose function is to inhibit intake following the ingestion of a food or a beverage. Satiety is one of the key mechanisms that controls human appetite allowing the adjustment of energy intake to energy needs.

The feeling of satiety occurs in response to a number of signals in the body that begin when a food or drink is consumed and continue as it enters the gut and is digested and absorbed. Hormones detect the amount of fat stored in the body, which will also affect satiety over the long term. Although individuals who are eating will feel the sensation of the stomach filling up, it can take some time after food is first eaten for the full range of satiety signals to reach the brain. Once that occurs and for some time afterwards, a person will experience feelings of satiety.

Description

After an individual eats, a number of factors interplay to stop further food intake. This is known as the Satiety Cascade and was first described in the late twentieth century by Professor John Blundell and his team of researchers at the University of Leeds in the United Kingdom. At the start of a meal, sensory factors such as the taste, smell, and texture of food stimulate eating, but then as eating progresses, people develop a sensory habituation to the ingested foods, which slows eating. Meanwhile, signals from the gastrointestinal tract and the rise in blood sugar levels progressively undermine the motivation to eat and bring eating to an end, a sensation known as satiation. Satiation signals need to be sufficiently powerful to counter the sensory appeal of the food that stimulated eating in the first place. The palatability of a food can decrease satiation, and trials have demonstrated that people will eat a palatable meal that is 44% larger than a neutral or unpalatable meal.

After satiation is reached for the specific sensory characteristics of a particular food, other foods with different sensory aspects may still retain their stimulatory power, so individuals continue to consume food until satiation signals are sufficiently powerful to counter the sensory appeal of all food options. This helps to explain why a person may feel full after eating a savory meal, but then still want to eat a sweet dessert.

Factors that influence satiety

Following the end of a meal, satiety occurs when numerous influences contribute to the inhibition of further intake of food for a certain time. The weight, volume, energy and nutrient content, and energy density of the meal determine the intensity and duration of satiety.

Foods that are high in fiber also enhance feelings of satiety as they are digested more slowly and slow the absorption of glucose into the bloodstream. This can prevent fluctuating blood sugar levels in the blood, which in turn can cause hunger pangs and disrupt normal appetite. Healthcare professionals recommended including plenty of high-fiber foods (e.g., wholegrain bread and cereals, beans, pulses, fruits, and vegetables) in the diet.

The addition of energy-dense foods (such as vegetables and wholegrains) with lots of water can increase satiety. Research has shown that soups and stews are particularly satisfying compared to a caloriematched equivalent of drier foods.

Caffeine and capsaicin (the active substance in chilis) have also been found to increase satiety and reduce subsequent energy intake. One study showed that a combination of capsaicin and green tea decreased hunger and increased satiety leading to a significant weight loss over a four-week period.

Chewing food for longer results in less food being eaten during the meal, as does paying more attention to food while eating and minimizing distractions by turning off the TV and other screens.

Precautions

Many other factors influence eating behavior and may override the body's satiety signals causing the individual to overeat, such as:

Interactions

Some evidence indicates that calories from liquids are less satiating than calories from solid foods. High calorie drinks, such as sweetened sodas and milkshakes, do not make individuals feel as full as compared with a calorie-matched solid food, which can lead to passive overconsumption of additional food to fill the perceived hunger. In addition, alcohol seems to stimulate appetite in the short term, so drinking alcohol is likely to encourage overeating.

QUESTIONS TO ASK YOUR DOCTOR

Complications

Despite the sophisticated mechanisms that exist to control energy intake, people often continue to eat when they feel satiated or resist eating when hungry. Under optimal conditions, eating should be well connected with hunger and satiation in a way that spontaneously leads to a close match between energy intake and expenditures. The current obesity epidemic suggests that dysfunctions often affect satiety and energy intake.

Parental concerns

Some parents worry because their children only pick at meals and eat very little. They want to encourage their children to eat more, but if a child is maintaining an average weight for his or her height and age, parents should not be concerned. Forcing children to eat when they are not hungry can lead to them ignoring their satiety and appetite controls, which in turn can lead to weight problems and possibly obesity later in life.

Conversely, other parents worry that their children overconsume food and do not seem to heed their satiety and appetite controls. Often children who are eating “empty calories” such as junk food and sodas will feel hungry more often and want to continue to eat even after they have consumed more calories than they need for the day, resulting in excess weight gain. Offering healthy food choices such as raw vegetables or fruit with a balancing protein can often curb a child's overeating.

Resources

BOOKS

Blundell, John, editor. Satiation, Satiety, and the Control of Food Intake. Oxford, UK: Woodhead, 2017.

Harris, Ruth. Appetite and Food Intake: Central Control. 2nd ed. Boca Raton, FL: CRC, 2017.

Tepper, Beverly J. and Martin Yeomans. Flavor, Satiety, and Food Intake. Hoboken, NJ: Wiley-Blackwell, 2017.

PERIODICALS

Almiron-Roig, Eva, Luigi Palla, Kathryn Guest, et al. “Factors that Determine Energy Compensation: A Systematic Review of Preload Studies.” Nutrition Reviews 71, no. 7 (July 2013): 458–73.

Blundell, John. “Making Claims: Functional Foods for Managing Appetite and Weight.” Nature Reviews Endocrinology 6, no. 1 (2010): 53–56.

Cassady, Bridget A., Robert V. Considine, and Richard D. Mattes. “Beverage Consumption, Appetite, and Energy Intake: What Did You Expect?” American Journal of Clinical Nutrition 95, no. 3 (2012): 587–93.

Drapeau, Vicky, Neil King, Marion Hetherington, et al. “Appetite Sensations and Satiety Quotient: Predictors of Energy Intake and Weight Loss.” Appetite 48, no. 2 (March 2007): 159–66.

WEBSITES

U.S. Department of Agriculture. “Food and Nutrition.” U.S. Department of Health and Human Services. https://www.usda.gov/topics/food-and-nutrition (accessed May 24, 2018).

U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015–2020 Dietary Guidelines for Americans. 8th ed. December 2015. http://health.gov/dietaryguidelines/2015/guidelines/ (accessed May 1, 2018).

ORGANIZATIONS

Academy of Nutrition and Dietetics, 120 S. Riverside Plaza, Ste. 2190, Chicago, IL, 60606-6995, (312) 899-0040, (800) 877-1600, amacmunn@eatright.org, http://www.eatright.org .

American Society for Nutrition, 9211 Corporate Blvd., Ste. 300, Rockville, MD, 20850, (240) 428-3650, Fax: (240) 404-6797, http://www.nutrition.org .

British Nutrition Foundation, New Derwent House, 69-73 Theobalds Rd., London, UK, WC1X 8TA, +44 20 7557-7930, postbox@nutrition.org.uk, http://www.nutrition.org.uk .

Center for Food Safety and Applied Nutrition, Food and Drug Administration, 5001 Campus Dr., HFS-009, College Park, MD, 20740-3835, (888) 723-3366, https://www.fda.gov .

Sarah Schenker

KEY TERMS
Appetite—
The desire to eat foods, usually due to hunger.
Energy density—
The amount of energy in a food per volume or weight.
Hormones—
Signaling molecules produced by glands that are transported by the circulatory system to target distant organs to regulate physiology and behavior.
Palatability—
The enjoyment and appeal of a food based not just on its flavor or taste but also how the food is perceived by an individual based on a state of deprivation or consumption.
Satiety—
The absence of hunger and having no desire to eat for a period following a meal.
Satiety cascade—
A series of behavioral and physiological events that occur following food intake and that inhibit further eating until the return of hunger signals.
Satiation—
The feeling of fullness and satisfaction after a meal.
  This information is not a tool for self-diagnosis or a substitute for professional care.