Lactose intolerance

What is Lactose Intolerance?

    Lactose intolerance occurs when the body lacks the necessary enzyme, lactase, to break down lactose, a sugar in milk and dairy products. Without sufficient lactase, the lactose remains undigested in the small intestine, leading to uncomfortable symptoms such as bloating, diarrhoea, and gas after consuming dairy. It's important to note that lactose intolerance differs from a milk allergy.

What are the causes of Lactose Intolerance?

    Lactose intolerance can affect both children and adults, and its causes vary:

    1. Hereditary Factors: Lactose intolerance often has a genetic component running in families. Over time, individuals may produce less lactase enzyme, leading to symptoms that typically manifest during adolescence or adulthood.

    2. Intestinal Damage: Sometimes, the small intestine ceases lactase production due to injury, disease, or infection. This loss of enzyme function can result in lactose intolerance.

    3. Prematurity: Premature babies may experience temporary lactose intolerance due to their underdeveloped digestive systems. However, this condition usually resolves on its own over time.

    4. Congenital Lactase Deficiency: In rare instances, individuals may be born with a complete inability to produce lactase enzyme, leading to severe lactose intolerance from birth.

What are the risk factors of Lactose Intolerance?

    Various factors can increase the likelihood of lactose intolerance for you or your child:

    1. Advancing Age: Lactose intolerance typically emerges in adulthood, which is rare in infants and young children.

    2. Ethnicity: Lactose intolerance is more prevalent among individuals of African, Asian, Hispanic, and American Indian heritage.

    3. Premature Birth: Premature infants may have lower lactase levels due to the delayed development of lactase-producing cells in the small intestine, which occurs late in the third trimester of pregnancy.

    4. Small Intestine Disorders: Conditions affecting the small intestine, such as bacterial overgrowth, celiac disease, and Crohn's disease, can lead to lactose intolerance.

    5. Cancer Treatments: Individuals who have undergone radiation therapy for stomach cancer or experienced intestinal complications from chemotherapy are at an increased risk of developing lactose intolerance.

What are the symptoms of Lactose Intolerance?

    Symptoms of lactose intolerance can manifest as follows:

    1. Abdominal bloating.

    2. Excessive intestinal gas.

    3. Nausea and vomiting.

    4. Stomach pain and cramps.

    5. Audible stomach gurgling or rumbling.

    6. Diarrhoea.

    These symptoms arise due to undigested lactose in the large intestine. After consuming lactose-containing foods, it takes approximately six to 10 hours to reach the large intestine, followed by an additional 24 to 36 hours to traverse through the large intestine. As a result, symptoms may occur within a day or two after lactose consumption.

What are the types of Lactose Intolerance?

    There are three types of lactose intolerance, each with distinct underlying causes resulting in lactase deficiency.

    1. Primary lactose intolerance:

    This is the most prevalent form, wherein individuals initially produce adequate lactase during infancy. However, as they transition from a milk-based diet to a varied one, lactase production naturally declines but remains sufficient for most people to digest dairy products into adulthood. In primary lactose intolerance, lactase production significantly diminishes by adulthood, leading to difficulty digesting milk products.

    2. Secondary lactose intolerance:

    This type occurs when the small intestine reduces lactase production due to an illness, injury, or surgery involving the small intestine. Conditions associated with secondary lactose intolerance include intestinal infections, celiac disease, bacterial overgrowth, and Crohn's disease. Treating the underlying disorder may help restore lactase levels and alleviate symptoms over time.

    3. Congenital or developmental lactose intolerance:

    This rare condition may occur in newborns due to a genetic lack of lactase enzyme activity inherited in an autosomal recessive pattern. Both parents must pass on the same gene variant for the child to be affected. Premature infants may also experience lactose intolerance due to insufficient lactase levels at birth.

When to see the doctor

    Schedule an appointment with your healthcare provider if you experience frequent symptoms of lactose intolerance after consuming dairy products, especially if you're concerned about maintaining adequate calcium intake.

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