General Studies Paper 2

Introduction

• Lactose intolerance is caused by a lessened ability or inability to digest lactose, a sugar found in dairy products. Humans vary in the amount of lactose they can tolerate before symptoms develop. Symptoms may include abdominal pain, bloating, diarrhea, flatulence, and nausea. These symptoms typically start thirty minutes to two hours after eating or drinking something containing lactose, with the severity typically depending on the amount consumed. Lactose intolerance does not cause damage to the gastrointestinal tract.

A disorder or not!

• Doctors do not consider lactose intolerance to be a disorder. They describe it as the digestive system’s reaction to milk sugar (lactose) which it cannot digest.
• The body needs an enzyme called lactase which is produced by the cells lining the small intestine, to digest lactose.
• If one is deficient in lactase, the undigested lactose passes on to the colon, where it produces extra gas and water, resulting in bloating, cramps and diarrhoea.
• Lactose intolerance thus produces symptoms which can be uncomfortable, but it is never dangerous.

Extremely common

• Lactose intolerance is so common that except for the 1-2% people who might experience serious bloating and cramps and nausea immediately after consuming dairy, almost every adult has lactose intolerance in various degrees.
• As one ages, there is a normal decline in the amount of lactase that the small intestine produces.
• Lactose intolerance is a specific digestive issue associated with the consumption of dairy products and ceases to be a problem when the person totally avoids or restricts milk products in the diet.
• But its symptoms can easily overlap with another common and chronic gastric disorders such as IBS, the pathogenesis of which is quite different.

Varies by ethnicity

• According to literature, estimates for lactose intolerance vary by ethnicity.
• The prevalence rate is 75-95% in African American and Asian ethnicities while it is estimated to be 18-26% amongst Europeans.
• Though there are specific tests like the hydrogen breath test to determine lactose intolerance, these tests do not have much use in clinical practice.
• This is a condition that is generally self-diagnosed and self-managed. The usual tests for detecting lactose intolerance are not available here or are expensive but clinical diagnosis seems to suffice.
• It is possible to develop secondary lactose intolerance all of a sudden following surgery or chemotherapy or if one has an infection, ulcerative colitis or Crohn’s disease which affects the small intestine. But this usually goes away once the small intestine regains health

Intolerance distinct from allergy

• The lactose intolerance is quite common among Asians — over 50% of the Indians are deficient in lactase — it is very easy to misdiagnose this condition, especially amongst the elderly.
• In the elderly, some malignancies like colon cancer can present themselves in the initial stages with atypical symptoms similar to that of the symptoms of lactose intolerance.
• The reaction is often immediate and severe in the case of milk allergy, while lactose intolerance will never lead to any serious disease or long-term complications.

Conclusion

• For persons with lactose intolerance who love to consume milk, there are options such as plant-based milk (soy/almond milk) or lactose-free milk. There are plenty of other food sources — yoghurt, tofu, nuts, spinach, broccoli, orange, lentils and legumes — that a lactose-intolerant person can depend on for calcium supplementation.