Although you may think of bacteria as potentially harmful organisms, millions of beneficial bacteria live in your digestive tract. More than 400 different species of bacteria can be found in your system, mostly in the large intestine, or colon, where they play an important role in maintaining a healthy digestive system and limiting growth of potentially infectious microorganisms. Foods that contain live cultures of these healthy bacteria are called probiotics. Although helpful for both sexes, certain types of probiotics may have extra benefits for women.
Probiotic foods high in calcium make especially good choices for women, who have a higher risk of osteoporosis than men, according to the Centers for Disease Control and Prevention. Adding extra calcium can help keep bones strong and healthy, and yogurt with live cultures is a good example of a calcium-rich probiotic, with about 400 milligrams of calcium in 8 ounces of plain, low-fat yogurt. An 8-ounce serving of yogurt also contains about 300 milligrams of phosphorus, another mineral essential for strong bones. Other probiotic dairy foods include kefir, a milk-based fermented drink, and milk enhanced with beneficial bacteria called Lactobacillus acidophilus. Although evidence is mixed, eating probiotic foods with these microorganisms might also help prevent vaginal yeast infections in women prone to this problem.
Some probiotic foods are vegetables that have been fermented with beneficial bacteria, helping keep the populations of these microorganisms high in your digestive tract. Fermented vegetables can also be high-fiber foods that help lower your risk of constipation, a condition more likely to affect women than men. Examples include sauerkraut, a tangy, sour-tasting food made by fermenting shredded cabbage with healthy bacteria. Sauerkraut contains about 4 grams of dietary fiber per cup, about one-sixth of the daily amount of 25 grams recommended by the 2010 Dietary Guidelines for Americans. A Korean dish called kimchi is another example of a vegetable-based probiotic food, but it's much spicier and stronger in flavor than sauerkraut. For either dish, opt for a low-salt version to help keep your salt consumption in a healthy range.
Some probiotic foods are made from soybeans fermented with beneficial bacteria. Examples include miso, a paste-like product made from soybeans and barley or rice that's often added to Asian dishes. Other examples include natto, a Japanese probiotic food also made from soybeans, and tempeh, another example that contains soybeans fermented with a beneficial fungus. These soy-based probiotics also contain natural chemicals called phytoestrogens that have weak estrogenic properties. According to the American Cancer Society, eating soy-based foods might help lower a woman's risk of breast cancer by blocking the action of natural estrogen. These foods might also have other benefits linked to their anti-inflammatory properties.
Probiotics are also available from health food stores as supplememts, usually in tablets or capsules. Some supplements contain a mixture of bacterial types, while others contain only Lactobacillus acidophilus. Experts at the University of Maryland report that probiotic supplements can be useful and beneficial, but may cause some gas, stomach upset or bloating. Discuss use of probiotic supplements or probiotic foods with your doctor or a registered dietitian to decide if adding them to your regimen might be helpful for you.