Lactose intolerance
Lactose intolerance is a common condition characterized by the inability to digest lactose, the sugar found in milk and dairy products. This condition arises when the body stops producing sufficient amounts of lactase, the enzyme responsible for breaking down lactose, often occurring after early childhood in a significant portion of the global population. As a result, individuals may experience symptoms such as stomach pain, gas, and diarrhea upon consuming lactose-containing foods. The severity of these symptoms can vary, but they typically resolve after the elimination of lactose from the diet.
Diagnosis often involves tracking dietary habits to identify the correlation between lactose consumption and symptom onset. While there is no cure for lactose intolerance, managing the condition generally involves avoiding dairy products or opting for lactase supplements available over-the-counter. Additionally, the growing availability of lactose-free dairy options provides further avenues for those affected. Understanding the prevalence and management strategies of lactose intolerance can help individuals make informed dietary choices, enhancing their quality of life while respecting diverse dietary needs and preferences.
Lactose intolerance
ANATOMY OR SYSTEM AFFECTED: Gastrointestinal system, intestines, stomach
DEFINITION: Lactose intolerance is an inability to break down and absorb milk sugar, known as lactose, resulting in stomach pain, gas, and diarrhea if lactose is consumed.
Causes and Symptoms
Lactose is a complex sugar commonly found in dairy products. It is composed of two simple sugars, glucose and galactose. In babies and young children, a gene produces an enzyme called lactase that breaks down lactose into its two component sugars, which are then absorbed into the bloodstream through the intestinal wall. In 65 to 75 percent of the world's population, sometime after early childhood, the lactase gene is “turned off.” It no longer synthesizes lactase, which prevents the digestion and absorption of lactose.
Normal bacterial inhabitants of the intestines synthesize lactase and break down the lactose molecules, producing large quantities of gas as a by-product. This can lead to cramping for the lactose-intolerant individual. The presence of lactose in the large intestine causes excessive amounts of water to move into the intestine, which can lead to diarrhea. Symptoms subside one to two days after the last lactose-containing food has been consumed.
Treatment and Therapy
Lactose intolerance can often be misdiagnosed as a host of gastrointestinal disorders, largely as a result of the commonness of its major symptoms, cramps and diarrhea. Typically, a dietary history must be kept. Patients with lactose intolerance will note an association between their symptoms and the consumption of milk products containing lactose. After elimination of these products from the diet, symptoms should not recur.
There is no cure for lactose intolerance; prevention of symptoms is the general course of action. Avoidance of foods that contain lactose—including milk, ice cream, and cheese—is usually the best recourse. For those who wish to indulge in these products, over-the-counter lactase pills are available; their use usually prevents symptoms of the disorder.
Perspective and Prospects
The vast majority of the world’s population is lactose intolerant, yet this disorder was not recognized until later in the twentieth century. Today, lactase supplements are available to help prevent symptoms for lactose-intolerant people who choose to consume dairy products. Alternatively, more and more dairy products are being manufactured as lactose-free; they can be consumed safely by the lactose-intolerant population.
Bibliography
Angima, Gloria, Yunyao Qu, Si Hong Park, and David C. Dallas. "Prebiotic Strategies to Manage Lactose Intolerance Symptoms." Nutrients, vol. 16, no. 7, 2024. DOI: 10.3390/nu16071002. Accessed 2 Apr. 2024.
Dobler, Merri Lou. Lactose Intolerance Nutrition Guide. Chicago: American Dietetic Association, 2002. Print.
Gracey, Michael, ed. Diarrhea. Boca Raton: CRC Press, 1991. Print.
Greenberger, Norton J. Gastrointestinal Disorders: A Pathophysiologic Approach. 4th ed. Chicago: Year Book Medical, 1989. Print.
Janowitz, Henry D. Your Gut Feelings: A Complete Guide to Living Better with Intestinal Problems. Rev. ed. New York: Oxford UP, 1995. Print.
"Lactose Intolerance--Genetics." MedlinePlus, 24 Mar. 2023, medlineplus.gov/genetics/condition/lactose-intolerance/. Accessed 2 Apr. 2024.
Mandl, Elise. "5 Signs and Symptoms of Lactose Intolerance." Healthline, 24 Jan. 2023, www.healthline.com/nutrition/lactose-intolerance-symptoms. Accessed 3 Aug. 2023.
Nelson, Maria. I'm Allergic to Milk. New York: Gareth Stevens, 2015. Print.
Peikin, Steven R. Gastrointestinal Health. Rev. ed. New York: Quill, 2001. Print.
Wood, Debra, and Brian Randall. "Lactose Intolerance." Health Library, Mar. 15, 2013.