Milk is a big beverage in a lot of households, especially those with kids. But is it time to change our dairy-swigging habits? Some recent studies say yes.
Americans are drinking 37 percent less milk today than they did in 1970, according to a Washington Post blog that analyzed data from the U.S. Department of Agriculture.
Why? The Post points to several reasons:
- Americans – especially young people – are choosing other beverages.
- Milk has become more expensive.
- And: Several studies have questioned whether milk actually does a body good.
More about those studies
"Subjects were asked to report on how much milk they had consumed as teenagers, and then they were followed to see if that was associated with a reduced chance of hip fractures later in life. It wasn't."
He also breaks down a recent study in The BMJ that followed adults in Sweden, age 39 and older:
"Milk consumption as adults was associated with no protection for men, and an increased risk of fractures in women. It was also associated with an increased risk of death in both sexes.
This wasn’t a randomized controlled trial, and no one should assume causality here. But there’s no association with benefits, and a significant association with harms."
Carroll notes that the U.S. government has long backed efforts – like the Got Milk campaign - to increase dairy consumption at home and abroad.
So, if milk isn't as beneficial as the government, nutritionists and our mothers once told us, should we still be drinking it?
If you don't have a milk intolerance or allergy, and you already drink it, "I think it's a positive part of a healthy diet," says Angela Zivkovic, an assistant professor in the UC Davis Department of Nutrition. "I haven't seen any convincing evidence that there's something about dairy that's unhealthful."
Full disclosure: Zivkovic's research has been funded by the California Dairy Research Foundation, which gets most of its financial support from the California Milk Advisory Board. Her current research is funded by the Dairy Research Institute, an arm of Dairy Management Inc.™, which promotes the industry nationally.
Zivkovic says she finds flaws in some of the recent research, including the BMJ study: "It's really difficult for the public to differentiate between all these different studies and the quality of the results," she says.
Zivkovic says the data for the BMJ study were obtained by asking people to estimate their dairy intake via a questionnaire. This type of self-reported information might not be accurate, she says, especially since the study's male participants reported their dairy intake just once, in 1997, and the female subjects reported it twice, once between 1987 and 1990, and then again in 1997.
On the flip side, Zivkovic says there are recent studies that found health benefits of dairy - but received much less press.
As an example, she points to a study that came out this year in the American Journal of Clinical Nutrition, finding that dairy consumption was associated with a lower risk of Type 2 diabetes. In this study, researchers measured biomarkers of dairy fat intake, instead of relying on self-reported dietary intake data, which, she says, is a more reliable way of measuring dairy’s impact on health.
Part of a healthy diet
So, back to the question: What to do about milk?
Linda Heller, manager of clinical nutrition services at Children's Hospital Los Angeles, says she encourages families to consume a variety of foods that are rich in calcium and Vitamin D. She recommends milk, as well as yogurt, cheese, dark green leafy vegetables and almonds, she says.
"There is little debate that calcium and Vitamin D are important dietary components to a healthy diet, and valuable for long-term health," Heller writes in an e-mail. "Encouraging families to offer low-fat dairy options and other calcium-rich foods will continue to be my practice."
She also has questions about the recent dairy studies. She writes:
"The research regarding the risks associated with milk consumption leaves me wondering if other factors such as physical activity, gender, size, age, medication, tobacco, alcohol and drug use, hormone levels and genetics were all controlled for in their investigation. We know that weight-bearing physical activity may play a far greater role in bone health than diet does, so recommendations surrounding physical activity remain a component to the guidance I offer."
What do you think of this milk research? Will recent studies have any impact on your - or your family's - dairy consumption? Tell us about it in the comments section below, or e-mail us at Impatient@scpr.org.