I have been lactose intolerant for the last year or so. Drinking a half cup of milk or eating a cream-based sauce is usually enough to give me cramps and mild diarrhea. I was wondering how any nutrients manage to get absorbed at all. Is my system still able to digest the carbohydrates, protein, and fat that I eat? I have lost some weight and was thinking that lactose-intolerance could be the reason. I’m also wondering whether drinking milk is an okay way for a lactose-intolerant person to cure or relieve constipation.
Lactose intolerance occurs when the cells lining the small intestine become deficient in the lactase enzyme that is required to digest the sugar lactose, the predominant sugar in milk. The most common form of lactose intolerance is primary lactase deficiency, an inherited characteristic that affects from 5 to 15 percent of adults of European origin, but much higher percentages of people of African or Asian origins. Even among people who inherit the deficiency, it generally does not appear until adolescence or young adulthood.
Secondary, or acquired lactase deficiency, can occur in someone without the genetic predisposition if he or she has another intestinal disease that alters the cells lining the small intestine so that lactose is not properly digested. These other conditions include Crohn’s disease, viral or bacterial infections of the intestinal tract, ulcerative colitis, cystic fibrosis, and infection of the small intestine by the parasite Giardia lamblia. Combinations of the primary and secondary types can occur. For instance, I have had many patients with rather mild lactose intolerance who become much more symptomatic after a bout of gastroenteritis. The increased milk intolerance generally returns to its previously mild state over a period of a couple of weeks as the intestinal lining repairs itself.
Lactase deficiency, whether primary or secondary, causes bloating, cramps, abdominal pain, and diarrhea after consumption of milk or milk products. Yogurt is usually tolerated because the bacterial process of yogurt production breaks down the lactose. Most people with severe lactase deficiency are aware that milk causes their symptoms, and they treat themselves by avoiding it. If someone has secondary lactase deficiency as a result of another condition, he or she may need to take special supplements. Otherwise, malnutrition is not a problem among those with lactose intolerance.
In answer to your last question, yes, if you could determine just the right amount of milk to drink to keep your stools soft, but without uncomfortable diarrhea, you could combat constipation. Unfortunately though, the symptom that usually disappears first when you reduce the amount of lactose taken in is the diarrhea. The uncomfortable bloating and cramping may persist if any lactose at all is being ingested. Therefore, I think for most people, trying to use this deficiency to control constipation won’t work very well. I don’t see any harm in trying, although increasing fiber in the diet will probably work better.
Lactaid treated milk and Lactaid pills, liquid, etc., all contain or are treated with lactase, which removes the lactose and allows people with this condition to drink milk without symptoms.