Lactose intolerance -- the inability to tolerate foods containing the sugar lactose, which is found in dairy products -- develops over time. Although lactose intolerance can be hereditary, the disorder rarely develops before age 2 and most often develops in late adolescence or adulthood. African-Americans, Asians, Native Americans and Hispanic-Americans are more likely to develop lactose intolerance than Caucasians. Some pregnant women may develop lactose intolerance for the first time during pregnancy, when dairy consumption often increases due to higher calcium needs.
Causes
Lactose intolerance is caused by the lack of an enzyme called lactase, which breaks down lactose in the intestine so your body can absorb it. Infants almost never have lactose intolerance -- a good thing since their diet consists entirely of milk. Not everyone has lactose intolerance to the same degree; some women can eat small or moderate amounts of dairy foods without any symptoms, but will experience symptoms when they up their intake in pregnancy.
Timing
Because adults of any age can develop lactose intolerance, development during pregnancy is possible, but lactose intolerance that shows up for the first time because of pregnancy is uncommon, according to nutritionist Sue Gilbert, writing for the website iVillage Pregnancy & Parenting. If you haven't been much of a dairy eater before pregnancy, it's possible that the symptoms of lactose intolerance have just now appeared because of your increased dietary intake of lactose. Many women of childbearing age don't consume large amounts of dairy products until they become pregnant. You may have been lactose intolerant before but never put it to the test by consuming dairy products.
Other Possible Causes
What appears to be lactose intolerance may actually be normal changes of pregnancy. During pregnancy, intestinal activity slows, which can cause more frequent stomach upsets such as vomiting, nausea, heartburn or feeling full for a long time after a meal. The symptoms of lactose intolerance normally appear 30 minutes to two hours after a meal and include diarrhea, gas, nausea, stomach cramping and bloating.
Coping Methods
If you do develop lactose intolerance while you are pregnant, you may still be able to consume dairy products if you take small amounts at a time. Many people find yogurt easier to digest than other lactose-rich foods, because the enzymes in yogurt are already partially digested by bacteria. Taking lactase tablets or drinking lactose-reduced milk can also help you tolerate dairy products in your diet without reducing your calcium intake.
