Milk Cultured
Acidophilus milk, buttermilk, kefir, kumiss, sour cream, yogurt
Cultured milks are dairy products whose lactose (milk sugar) has been digested by specialized microorganisms that produce lactic acid, which thickens the milk.
Acidophilus milk is pasteurized, whole milk cultured with Lactobacillus acidophilus. If you add yeast cells to acidophilus milk, the yeasts will ferment the milk, producing two low-alcohol beverages: kefir or kumiss.
Cultured buttermilk is pasteurized low-fat or skim milk cultured with Streptococcus lactis. Sour cream is made either by culturing pasteurized sweet cream with lactic-acid bacteria or by curdling the cream with vinegar.
Yogurt is milk cultured with Lactobacilli bulgaricus and Streptococcus thermophilus. Some yogurt also contains Lactobacillus acidophilus. Like meat, fish, poultry, and eggs, cultured milks are a good source of high-quality proteins with sufficient amounts of all the essential amino acids.
The primary protein in cultured milks is casein in the milk solids; the whey contains lactalbumin and lactoglobulin. About half the calories in cultured whole milks come from milk fat, a highly saturated fat. Cultured milks made from whole fresh milk are a significant source of fat, saturated fat, and cholesterol. Cultured milks made from fresh low-fat milk or skim milk are not.
Cultured milk products made from fresh whole milk contain moderate amounts of vitamin A from carotenoids, yellow plant pigments eaten by milk cows. Because vitamin A is fat-soluble, it is removed when fat is skimmed from milk; low-fat and skim-milk products have less vitamin A than whole-milk products.
For example, one cup of plain whole-milk yogurt has 243 IU vitamin A (11 percent of the RDA for a woman, 8 percent of the RDA for a man), while one cup plain lowfat yogurt has 125 IU vitamin A, and one cup plain skim-milk yogurt has only 17 IU vitamin A. Cultured milks made from vitamin D-fortified milk contain vitamin D. All milk products are good sources of B vitamins, and our best source of calcium.
One cup of plain yogurt made with low-fat milk has 452 mg/calcium; one cup of non-fat buttermilk, 284 mg. Flavored yogurt or yogurt with added fruit or preserves, is much higher in sugar and may have small amounts of fiber (from the fruit).
Fat and Cholesterol Content of Cultured Milks (1 cup/8 ounces)
Milk Total fat (g) Saturated fat (g) Cholesterol (mg)
Buttermilk (lowfat) 2 1.3 10
Sour cream (reduced fat /
1 tablespoon) 1.8 1.1 6
Yogurt, plain, whole milk 8 5.1 32
Yogurt, plain lowfat 3.8 2.5 15
Yogurt, plain, skim milk 0.4 0.3 5
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Non-fat products for adults, whole milk products for children. The American Academy of Pediatrics warns against giving children skim-milk products, which may deprive them of fatty acids essential for proper growth.
Controlled cholesterol, controlled saturated fat diet
Lactose intolerance diet
Sugar-free diet (flavored yogurt or yogurt made with sugared fruit)
Look for: Tightly sealed, refrigerated containers that feel cold to the touch. Check the date on the container to buy the freshest product.
Refrigerate all cultured milk products. At 40°F, buttermilk will stay fresh for two to three weeks, sour cream for three to four weeks, and yogurt for three to six weeks. Keep the containers tightly closed so the milks do not absorb odors from other foods.
Do not “whip” yogurt or sour cream before adding to another dish. The motion will break the curds and make the product watery.
Cultured milk products are more unstable than plain milks; they separate quickly when heated. Stir them in gently just before serving.
Freezing. Ordinarily, cultured milk products separate easily when frozen. Commercially frozen yogurt contains gelatin and other emulsifiers to make the product creamy and keep it from separating. Freezing inactivates but does not destroy the bacteria in yogurt; if there were live bacteria in the yogurt when it was frozen, they will still be there when it’s thawed. Nutritionally, frozen yogurt made from whole milk is similar to ice cream; frozen yogurt made from skim milk is similar to ice milk.
Protection against osteoporosis. The most common form of osteoporosis (literally, “bones full of holes”) is an age-related loss of bone density most obvious in postmenopausal women. Starting at menopause, women may lose 1 percent a year of their bone density every year until they die. Men also lose bone, but at a slower rate. As a result, women are more likely than men to suffer bone fractures. Six of seven Americans who suffer a broken hip are women. A life-long diet with adequate amounts of calcium can help stave off bone loss later in life. Current studies and two National Institutes of Health Conferences suggest that postmenopausal women who are not using hormone replacement therapy should get at least 1,500 mg calcium a day, the equivalent of the calcium in slightly more than three cups yogurt made with nonfat milk.
Protection against antibiotic-related illness. Gastric upset, primarily diarrhea, is a common side effect of antibiotic therapy because antibiotics eliminate beneficial bacteria in the gastrointestinal tract along with harmful microorganisms. In 2008, a report in the British Medical Journal confirmed earlier studies suggesting that hospitalized patients on antibiotics who were given “probiotic” cultured milks—yogurts containing beneficial microorganisms—had a significantly lower risk of developing antibiotic-related diarrhea. As an example, the following chart lists the microorganisms in the yogurts made and sold under the Dannon brand names.
Product “Good” Microorganisms in the Yogurt
Activia Bifidus Regularis, Streptococcus thermophilus, Lactobacillus bulgaricus
DanActive Lactobacillus casei Immunitas, Streptococcus thermophilus, Lactobacillus bulgaricus
Light & Fit Lactobacillus acidophilus, Streptococcus thermophilus, Lactobacillus bulgaricus
Danimals Lactobacillus GG (LGG), Streptococcus thermophilus, Lactobacillus bulgaricus
Reduced risk of hypertension (high blood pressure). In 2008, a team of researchers from Brigham and Women’s Hospital and the Harvard School of Public Health report in the American Heart Association journal Hypertension that women who consume two or more servings of fat-free milk and milk products a day reduce their risk of high blood pressure by 10 percent, compared to women who consume these products less than once a month. The finding is specific to low-fat milk products; it does not apply to milk products with higher fat content or to calcium and vitamin D supplements.
Increased risk of cardiovascular disease. Like other foods from animals, whole milk is a source of cholesterol and saturated fats that increase the amount of cholesterol circulating in your blood and raise your risk of heart disease. To reduce the risk of heart disease, the National Cholesterol Education Project recommends following the Step I and Step II diets.
The Step I diet provides no more than 30 percent of total daily calories from fat, no more than 10 percent of total daily calories from saturated fat, and no more than 300 mg of cholesterol per day. It is designed for healthy people whose cholesterol is in the range of 200–239 mg/dL.
The Step II diet provides 25–35 percent of total calories from fat, less than 7 percent of total calories from saturated fat, up to 10 percent of total calories from polyunsaturated fat, up to 20 percent of total calories from monounsaturated fat, and less than 300 mg cholesterol per day. This stricter regimen is designed for people who have one or more of the following conditions:
Existing cardiovascular disease
High levels of low-density lipoproteins (LDLs, or “bad” cholesterol) or low levels of high-density lipoproteins (HDLs, or “good” cholesterol)
Obesity
Type 1 diabetes (insulin-dependent diabetes, or diabetes mellitus)
Metabolic syndrome, a.k.a. insulin resistance syndrome, a cluster of risk factors that includes type 2 diabetes (non-insulin-dependent diabetes)
Allergy to milk proteins. Milk and milk products are among the foods most often implicated as a cause of the classic symptoms of food allergy, upset stomach, hives and angioedema (swelling of the face, lips, and tongue). Lactose intolerance.
Lactose intolerance is an inherited metabolic deficiency. People who are lactose intolerant lack sufficient amounts of lactase, the intestinal enzyme that breaks lactose into glucose and galactose, its easily digested constituents. Two-thirds of all adults, including 90 to 95 percent of all Asians, 70 to 75 percent of all African Americans, and 6 to 8 percent of northern Europeans are lactose intolerant to some extent. When they drink milk or eat milk products, the lactose remains undigested in their gut, to be fermented by bacteria that produce gas and cause bloating, diarrhea, flatulence, and intestinal discomfort. However, the Lactobacillus acidophilus bacteria added to acidophilus milk and some yogurts digest lactose, converting it to ingredients lactase-deficient people may be able to consume without discomfort.
Lactose Content of Cultured Milk Products vs. Lactose in Whole Fresh Milk
Acidophilus milk 6g/cup
Buttermilk 9g/cup
Yogurt (low-fat) 12g/cup
Whole fresh milk 12g/cup
Source: Briggs, George M., and Calloway, Doris Howes, Nutrition and Physical Fitness (Holt, Rinehart & Winston, 1984).
Galactosemia. Lactose, the sugar in milks, is a disaccharide (“double sugar”) made of one molecule of glucose and one molecule of galactose. People with galactosemia, an inherited metabolic disorder, lack the enzymes needed to convert galactose to glucose. Babies born with galactosemia will fail to thrive and may develop brain damage or cataracts if they are given milk. To prevent this, they are kept on a milk-free diet for several years, until their bodies have developed alternative ways by which to metabolize galactose. Pregnant women who are known carriers of galactosemia may be advised to avoid milk while pregnant, lest the unmetabolized galactose in their bodies damage the fetus. Genetic counseling is available to identify galactosemia carriers.
Tetracyclines (Declomycin, Minocin, Rondomycin, Terramycin, Vibramycin, et al.). The calcium ions in milk products bind with tetracyclines to form insoluble compounds your body cannot absorb. Taking tetracyclines with acidophilus milk, buttermilk, sour cream, or yogurt makes the drugs less effective.
