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Milk Got proof?

We assess the evidence behind the dairy industry's ads and critics' claims.


UDDER CONFUSION? Britney Spears (top) promotes milk's healthfulness for the dairy industry. Ads sponsored by People for the Ethical Treatment of Animals (bottom) send the opposite message.


In those ubiquitous dairy-industry ads, milk-mustached celebrities say a lot more than just "Got milk?" Teen idol Britney Spears tells teenagers to drink "four glasses of milk every day," singer Marc Anthony says milk can "help prevent osteoporosis," and Larry King says, "a healthy diet rich in low-fat dairy products may help lower the risk of high blood pressure." In 2000, the Physicians Committee for Responsible Medicine (PCRM), a group that promotes a vegan diet and preventive medicine, petitioned the Federal Trade Commission (FTC) to investigate whether the milk industry has evidence to back those claims.

Also in 2000, People for the Ethical Treatment of Animals (PETA), an animal-rights group, began sponsoring spoof ads questioning the healthfulness of cow's milk. One features a crying baby under the words "Got sick kids?" In September 2000, the group apologized to then New York Mayor Rudolph Giuliani for using his milk-mustached face on a billboard that said, "Got prostate cancer?" PETA says that milk is linked to an array of possible health problems, including indigestion, coronary heart disease, diabetes, and prostate cancer.

Who's right? The dairy industry and many nutrition experts say the issues raised by PCRM and PETA are ideologically motivated. But Consumers Union's assessment suggests that several of those issues cannot be so easily dismissed. Here are the major health concerns raised by those milk critics, followed by our evaluation of the evidence and what it means for those who love or loathe milk.


Does milk strengthen bones?
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Milk-industry ad: Singer Leann Rimes says, "Drink 1 percent milk now and you may not have to worry about osteoporosis when you're old."

Milk's critics: Milk has not been proved to reduce the risk of osteoporosis, and it may even harm the bones.

CU's evaluation: Both PCRM and PETA cite a review of the medical literature by researchers at the University of Alabama, Birmingham who found the evidence that dairy products help prevent osteoporosis and broken bones to be "inconclusive." But a more extensive review, by Robert Heaney, M.D., a calcium researcher at Creighton University in Omaha, found stronger evidence of milk and dairy's bone-strengthening effects.

Milk critics also point to a 12-year Harvard study of nearly 80,000 female nurses, in which high milk intake appeared to increase the risk of fractures. Diane Feskanich, Sc.D., an epidemiologist and lead author of the study, believes the reason may lie in the nurses' family histories. It may be that those who drank the most milk did so because they faced the highest risk--but it was "too little, too late," she says.

Recommendation: While there's no proof that milk wards off osteoporosis, it is high in calcium and vitamin D--essential nutrients for building and maintaining strong bones, according to a recent National Institutes of Health consensus panel. Some evidence suggests that milk and yogurt may be better for the bones than cheese, since the high sodium, phosphate, and protein content of most cheeses may tend to counteract their calcium content. People who don't want to consume dairy products can get the calcium they need (1,000 milligrams a day for adults under age 50; 1,200 to 1,500 milligrams after age 50) by eating lots of dark-green leafy vegetables, beans, and calcium-fortified products, or by taking enough supplemental calcium to reach their targeted intake. And they can generally get enough vitamin D from fatty fish and occasional exposure to sunlight.


Does milk help or harm the heart?
Milk-industry ad: "Dairy makes the difference in DASH" (Dietary Approaches to Stop Hypertension).

Milk's critics: There's no proof that dairy products reduce blood pressure, and they may help clog the coronary arteries.

CU's evaluation: In theory, the minerals in milk might help lower blood pressure. And in the 1997 DASH study, Government-sponsored researchers conclusively showed that a diet rich in fruits, vegetables, and low-fat dairy foods could reduce blood pressure, compared with both a high-produce, nondairy diet and the average American diet. But claiming that dairy made the difference is "speculative," says lead author Lawrence Appel, M.D., of the Johns Hopkins Medical Institutions, since the study wasn't designed to identify which foods affected blood pressure. And the DASH diet was higher not just in low-fat dairy foods but also in several vegetables--and, in turn, several key nutrients--than even the high-produce comparison diet.

As for PETA's coronary disease assertion, it's true that the saturated fat in whole milk can contribute to the high cholesterol levels that help clog the arteries. But consuming less of that fat, in part by switching to lower-fat milk, can help reduce cholesterol.

Recommendation: Choose skim or low-fat milk over whole milk to reduce saturated-fat intake and possibly to help lower blood pressure, as part of a diet rich in fruits and vegetables.


Does milk promote or fight cancer?
Milk-industry ad: Basketball's Dennis Rodman says, "Three glasses a day give the average man all the calcium he needs. Maybe I should drink six."

Milk's critics: Ads fail to disclose that milk is linked to prostate cancer.

CU's evaluation:Though the dairy-industry ads make no claims about cancer, they do imply a level of safety that's not proved. Full-fat dairy products, like other fatty foods, may possibly increase the risk of certain cancers. And in 1998, a large study from Harvard found that men who drank at least two glasses a day of skim or low-fat milk were more likely to develop advanced prostate cancer than those who drank no milk. Another large Harvard study, similarly linked low- or no-fat milk with increased prostate-cancer risk. Overall, however, the evidence has been inconsistent, with several studies failing to support that association.

Other investigators are reporting provocative findings that dairy and calcium might help protect against precancerous intestinal polyps and perhaps colon cancer. For example, a recent study from the Fred Hutchinson Cancer Research Center in Seattle found that people who consumed the most low-fat dairy products or took calcium supplements regularly had the lowest colon-cancer risk. And a new, not-yet-published Harvard report, based on the pooled results of 10 large studies, similarly found the least likelihood of colon cancer among the most avid milk drinkers. In theory, the calcium in milk may help remove certain acids linked to polyps and colorectal cancer.

Recommendation: The research on milk and prostate cancer--as well as colon cancer--is certainly worth watching. But CU's medical consultants say the evidence so far is too inconclusive to warrant getting either less or more than the USDA-recommended intake of low-fat dairy products--two to three servings a day--to reduce the risk of either type of cancer.


Avoid milk, avoid gas?
Milk-industry ad: Actress Whoopi Goldberg says, "Lucky for us lactose-intolerant folks, there's lactose-free milk."

Milk's critics: Lactose-intolerant people should not drink cow's milk in any form.

CU's evaluation: Lactose intolerance--a common, inherited inability to break down the milk sugar lactose--can cause stomach-ache, flatulence, and diarrhea. But despite PETA's contention that the condition is "our body's natural adverse reaction to something we shouldn't be putting into it," our medical consultants say there's no reason why people who are lactose intolerant can't have lactose-free milk or regular milk to which they add lactose-digesting enzymes.

Research suggests that some people who think they're lactose intolerant may not actually have the condition, and that many who do have it can adapt to dairy foods--particularly yogurt, since the bacteria it contains help digest the lactose.

Recommendation: Lactose-intolerant individuals can drink lactose-free or enzyme-treated milk. Or they could try gradually adapting to dairy by regularly consuming a little milk or yogurt with food and, if that causes no symptoms, consuming them more often and in larger amounts.


Is milk safe for kids?
Milk-industry ad: TV moms say, "Milk's essential nutrients will always be in style, which is why your kids should drink it."

Milk's critics: Milk proteins are linked to colic, milk allergy, and type 1 (insulin-dependent) diabetes.

CU's evaluation: Cow's milk can cause gastrointestinal discomfort in babies under a year old, because they can't digest the protein. Moreover, 2 to 3 percent of infants under that age may have an allergic reaction to milk protein. (Most outgrow the allergy by age 3.) Some research suggests that such early exposure to the protein may also harm the insulin-producing cells in the pancreas and increase the risk of type 1 diabetes. So the American Academy of Pediatrics advises parents not to give regular cow's milk to babies under age one.

In infant formulas based on cow's milk, the proteins are altered to make them digestible and, in theory, less likely to increase the diabetes risk. Special hypoallergenic formulas are also available.

Recommendation: Parents who think their child is allergic to or intolerant of milk should ask their pediatrician to confirm it. Milk is an efficient way for children over age one (as well as teens) to get their calcium and other needed nutrients.

in http://babysvc.consumerreports.org/baby ... opic=todfo