Lactose intolerance describes a digestive disorder that occurs when the cells lining the small intestine fail to produce adequate amounts of the enzyme lactase. Milk and other dairy products contain a sugar known as lactose. Because lactose is a complex sugar, a combination of glucose and galactose, your body needs lactase to break it down into the smaller molecules for absorption. Lactose intolerance causes digestive symptoms that may feel like weight gain in adults, but can also cause weight loss in young children.
Symptoms
Your body absorbs most of the nutrients from food through the lining of the small intestine. Without lactase, the lactose remains in the small intestine and continues to the large intestine. The bacteria in the large intestine attempt to break down the lactose through the process of fermentation. Fermentation produces gas and the gas causes the uncomfortable digestive symptoms, including abdominal bloating and cramps. Lactose intolerance also causes diarrhea and nausea. These symptoms typically begin between 30 minutes and two hours after consuming dairy products.
Adults
Approximately 30 million adults in the United States develop some degree of lactose intolerance by the age of 20, according to MedlinePlus. For most people, their bodies lose the ability to produce lactase slowly over time. Doctors refer to this type of lactose intolerance as primary lactose intolerance. Adults who continue to consume dairy products may feel as they have gained weight due to the excessive gas and bloating.
Treatment
To reduce the feeling of weight gain and bloating, remove dairy products from your diet. Most people can slowly add in some dairy and tolerate it without the onset of symptoms, according to the National Digestive Diseases Information Clearinghouse. Choose products lower in lactose, like cheese, or buy lactose-free products that already contain the lactase enzyme for easy digestion. Because there is no treatment to promote your small intestine to produce lactase, you must control your symptoms by making these dietary changes.
Young Children
Premature babies sometimes suffer from a lactase deficiency due to immature cells lining the small intestine. In these cases, the infant may experience a period of slow growth or weight loss until doctors determine the cause of the excessive gas, increased number of stools and feeding problems. Infants born to term and young children rarely show signs of lactose intolerance until at least age 3, according to MedlinePlus. At that point, the child relies less upon milk for nutrition so weight loss becomes less of a concern.
