Sour stomach? Could be lactose. Take it easy on your stomach by
learning more about this commons condition and how you easily find dairy alternatives.
According to research or other evidence, the following self-care steps may be helpful:
- Try lactase
- Take over-the-counter products containing lactase enzyme when
consuming foods containing lactose
- Check out calcium
- Take a calcium supplement providing 500 to 1,000 mg per day
regularly if you avoid dairy products
- Choose dairy products wisely
- Try using reduced-lactose milk or yogurt to see if you can
These recommendations are not comprehensive and are not intended to replace
the advice of your doctor or pharmacist. Continue reading the full lactose intolerance article
for more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and
lifestyle changes that may be helpful.
About lactose intolerance
Lactose intolerance is the impaired ability to digest lactose (the naturally occurring
sugar in milk). The enzyme lactase is needed to digest lactose, and a few
children and many adults do not produce sufficient lactase to digest the milk sugar. The
condition is rare in infants.
Only one-third of the population worldwide retains the ability to digest lactose into
adulthood. Most adults of Asian, African, Middle Eastern, and Native American descent are
lactose intolerant. In addition, half of Hispanics and about 20% of Caucasians do not produce
sufficient lactase as adults.1
A simple test for lactose intolerance is to drink at least two 8-ounce glasses of milk on
an empty stomach and note any gastrointestinal symptoms that develop in the next four hours.
The test should then be repeated using several ounces of cheese (which does not contain much lactose). If
symptoms result from milk but not cheese, then the person probably has lactose intolerance. If
symptoms occur with both milk and cheese, the person may be allergic to dairy products (very
rarely can lactose intolerance be so severe that even eating cheese will cause symptoms). In
addition to gastrointestinal problems, one study has reported a correlation in women between
lactose intolerance and a higher risk of
depression and PMS.2 However,
this study is only preliminary and does not establish a cause-and-effect relationship.
Product ratings for lactose
preventing deficiency if dairy products are avoided only)
What are the symptoms?
In people with lactose intolerance, consuming foods containing lactose results in
intestinal cramps, gas, and diarrhea.
Over the counter lactase (Lactaid®,
Dairy Ease®), an enzyme that breaks down lactose, is used to either pre-treat milk or to
be taken during the ingestion of dairy products.
A lactose-free diet is the most effective means of controlling the symptoms of lactose
malabsorption in a person with lactase deficiency. However, some lactose-intolerant people can
drink milk that has been predigested by the
addition of lactase. Those individuals who must avoid dairy products should take supplemental
Dietary changes that may be helpful
Although symptoms of lactose intolerance are triggered by the lactose in some dairy products, few lactose-intolerant people need to
avoid all dairy. Dairy products have varying levels of lactose, which affects how much lactase
is required for proper digestion. Milk, ice cream, and yogurt contain significant amounts of
lactose—although for complex reasons yogurt often does not trigger symptoms in
lactose-intolerant people. In addition, lactose-reduced milk is available in some supermarkets
and may be used by lactose-intolerant people.
Many people with lactose maldigestion tolerate more lactose in experimental studies than in
everyday life, in which their symptoms may result from other carbohydrates as well. Sucrose
and the indigestible carbohydrates lactulose and fructooligosaccharides (FOS) have all been
shown to produce symptoms in lactose-intolerant and milk-intolerant people.3
Vitamins that may be helpful
Supplemental sources of the enzyme lactase
may be used to prevent symptoms of lactose intolerance when consuming lactose-containing dairy
products. Lactase drops may be added to regular milk 24 hours before drinking to reduce
lactose levels. Lactase drops, capsules, and tablets may also be taken orally, as needed,
immediately before a meal that includes lactose-containing dairy products. The degree of
lactose intolerance varies by individual, so a greater or lesser amount of oral lactase may be
needed to eliminate symptoms of lactose intolerance.
Researchers have yet to clearly determine whether lactose-intolerant people absorb less calcium. As lactose-containing foods are among
the best dietary sources of calcium, alternative sources of calcium (from food or supplements)
are important for lactose-intolerant people. A typical amount of supplemental calcium is 1,000
mg per day.
supplements do not appear to be effective in reducing the signs and symptoms of lactose
intolerance. In a preliminary trial, people with lactose intolerance were given
Lactobacillus acidophilus supplements twice daily for seven days, but failed to show any
improvement in symptoms or laboratory measurements of lactose digestion.4
Are there any side effects or interactions?
Refer to the individual supplement for information about any side effects or interactions.
1. Gudmand-Hoyer E. The clinical significance of disaccharide
maldigestion. Am J Clin Nutr 1994;59(3):735–41S.
2. Ledochowski M, Sperner-Unterweger S, Fuchs D. Lactose malabsorption is
associated with early signs of mental depression in females: a preliminary report. Dig Dis
3. Teuri U, Vapaatalo H, Korpela R. Fructooligosaccharides and lactulose
cause more symptoms in lactose maldigesters and subjects with pseudohypolactasia than in
control lactose digesters. Am J Clin Nutr 1999;69:973–9.
4. Saltzman JR, Russell RM, Golner B, et al. A randomized trial of
Lactobacillus acidophilus BG2FO4 to treat lactose intolerance. Am J Clin Nutr