After spending a day with her boyfriend's family recently, my daughter marveled, "They only drink whole milk!" That milk was delicious, she reported, even after the container had sat on the counter for a while.

My darling child, whom I'll send to college in a few months, had never tasted whole milk before.

Milk in our house is almost always skim. (The exception: reduced-fat chocolate milk, which my son and daughter enjoy as an occasional treat.) I don't recall making a conscious choice; when I started buying skim milk, I probably was caught up in the fat-phobic zeitgeist of the mid-'90s.

In recent months, though, I've taken note of several provocative studies suggesting that there may be some benefit to dairy foods that, like whole milk, contain some or gobs of fat. One, published in 2005, found that high intake of whole milk, cheese, butter and other high-fat dairy foods corresponded with reduced risk of colorectal cancer. A 2009 study found an association with reduced risk of dying from cardiovascular disease. And still another, published in December, found a lowered risk of diabetes among people age 65 and older who consumed lots of whole-fat dairy.

But those isolated studies are not enough to sway nutrition experts in favor of reverting to whole milk. The case against whole milk turns on its saturated fat, which has been shown to raise the risk of cardiovascular disease and diabetes. It also packs a sizable caloric punch.

"I don't think there's been a shift yet," says Greg Miller, executive vice president of science and research for the National Dairy Council, "but there's a lot of interesting science that's emerging that may cause us to revise our thinking about fat-free dairy."

Until such a shift should occur, says Beth Thayer, a spokeswoman for the American Dietetic Association, "the public-health message is to choose dairy, but low-fat or fat-free."

"Milk has all these really great nutrients," Thayer says. Those include protein, calcium, potassium, magnesium, Vitamin D and Vitamin A. Drinking adequate amounts of milk promotes bone health and may help prevent cardiovascular disease and diabetes, she adds. That's why the new Dietary Guidelines for Americans 2010 are expected to continue calling for two to three servings of low- or nonfat dairy daily.

In the same vein, new school-lunch standards expected to be implemented by the 2012-13 academic year would require schools to serve only non-fat or low-fat milk. Suzanne Murphy, a member of the Institute of Medicine committee on whose recommendations the new standards will largely be based, says serving high-calorie, high-fat whole milk with school lunch would leave too little room for all the required nutrients within the allowable ranges of calories and fat.

But that's the rule for schools. "That does not mean that if a child is underweight he shouldn't have 2-percent-fat [milk] at home," Murphy says, especially if a little fat makes the milk more palatable. (It's worth noting that my daughter's boyfriend and his siblings, athletes all, are very slender; I imagine they easily burn off whole milk's calories and fat without even trying.)

And the guidelines are different for babies. Jatinder Bhatia, chairman of the American Academy of Pediatrics nutrition committee, says most kids should be given whole milk until they are 2 years old. "Adult goals for cutting back on total fat, saturated fat, trans fat and cholesterol aren't meant generally for children younger than 2 years," he says. "Fat is an essential nutrient that supplies the energy, or calories, children need for growth and active play and should not be severely restricted."

An exception: If a child is overweight or has a family history of cardiovascular disease or high blood pressure, the academy recommends switching to reduced-fat milk at 12 months.

Once children are older, though, parents may have a tough time getting kids to make the switch. That's when rigid adherence to dietary guidelines may backfire, says the National Dairy Council's Miller. "The average mom doesn't understand that it takes 15 exposures [to a new food] before a kid takes a liking," he says. "If the mom is pouring fat-free milk down the drain [because her child doesn't like it], she may move on to juice," which delivers far fewer nutrients per calorie than milk does.

"We need to be much more flexible in our approach" to dietary advice, suggests Miller, whose organization doesn't mind which kind of milk you drink, so long as you're drinking enough. He wants to move away from such issuing such restrictions as "don't eat fat."

"We've done that for 30 years in the Dietary Guidelines for Americans, and look where it's got us," he observes. "A population that's overweight and undernourished, selecting nutrient-poor foods."

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