Lactose intolerance symptoms manifest upon consumption of dairy products and other lactose-containing foods. While lactose intolerance isn't the same as a milk allergy, the symptoms can, nevertheless, be quite uncomfortable and are generally more severe with larger quantities of dairy. Unlike allergic reactions, symptoms of lactose intolerance are strictly related to the gastrointestinal tract.
Gas
One of the most notable features of lactose intolerance is that consumption of dairy leads to development of significant abdominal gas. If you're lactose intolerant, you don't produce the enzyme lactase, which digests the lactose sugar in milk and other dairy. As a result, lactose passes into your lower gastrointestinal tract, where bacteria degrade it, explain Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry." The bacteria produce copious amounts of gas as a byproduct of their digestion of lactose.
Bloating and Cramping
Formation of large quantities of gas in the gastrointestinal tract can lead to bloating and cramping, which are also hallmark symptoms of lactose intolerance, notes MedlinePlus.com. As gas forms in the lower intestine, it produces pockets of intestinal distention. The stretching of the intestine as gas bubbles move through is very uncomfortable and can lead to painful cramping sensations. You may be able to get some relief from the cramping by using an over-the-counter product such as Gas-X, which breaks up gas bubbles.
Diarrhea
Some individuals also experience diarrhea as a result of dairy consumption if they're lactose intolerant. Typically, this occurs in individuals who are very sensitive to lactose or who unwittingly consume dairy in very large quantities. The reason for the diarrhea is that as lactose passes undigested into the lower gastrointestinal tract, it pulls water into the gut. Generally, the lower intestine absorbs water out of the gut, resulting in solid stool formation. Significant water in the lower intestine leads to passing of very soft stools.
References
- "Biochemistry"; Reginald Garrett, Ph.D. and Charles Grisham, Ph.D.; 2007
- MedlinePlus: Lactose Intolerance
