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Low-Fat Milk: It Does a Blood Pressure Good

By Janis Jibrin, M.S., R.D.

Switching from whole or two-percent milk to skim or one-percent will save you as many as 70 calories. And calorie cutting isn’t the only benefit you may get from choosing the slimmer sip: A recent study suggests that it may also have a major impact on your blood pressure.

The Harvard study, which tracked nearly 29,000 women ages 45 and older for 10 years, found that women who drank two or more daily servings of low-fat dairy reduced their risk for developing high blood pressure by 10 percent compared to those who drank less.1 Those who downed high-fat dairy saw no blood pressure benefits.

What’s the connection between low-fat milk and blood pressure? The study authors offer a range of possible explanations. First, low-fat milk is high in calcium, which plays a major role in blood pressure regulation. Second, calcium may help you lose weight, and weight loss may help to reduce blood pressure. Finally, low-fat milk is fortified with vitamin D, which helps regulate blood pressure directly and may also help you absorb more calcium. Whole milk has all the same nutrients as skim and one-percent milk, so why didn’t it have any effect on blood pressure? Researchers speculate that the saturated fat in whole milk may contribute to clogged arteries and obesity—two factors that can increase blood pressure.

Now, let’s look at the stats: A third of Americans have high blood pressure, or hypertension. (Check out the Blood Pressure Categories chart from the National Heart Lung and Blood Institute.) If you’re overweight, your risk for hypertension increases. This condition may set you up for heart disease, stroke, kidney disease and complications during pregnancy. So, if something as simple as switching to skim or one-percent milk helps, it’s well worth it. If you’re worried about the taste, don’t be; after a few weeks, your taste buds will adjust. If you’ve been drinking whole or two-percent, first switch to one percent; then see if you can switch to skim after a few weeks. Check out the Smart Balance 14-day meal plan for ideas on how to incorporate more skim and one-percent milk into your diet.

You may also lower your blood pressure by losing weight, getting at least 30 minutes of physical activity daily, reducing your sodium intake, and eating a diet rich in fruits and veggies. If it’s still high, you may want to ask your doctor about medications that can lower blood pressure.

1 Wang, L. et al. Dietary Intake of Dairy Products, Calcium, and Vitamin D and the Risk of Hypertension in Middle-Aged and Older Women. Hypertension. 2008;51:1073-1079



Comments

Posted by Elise Malmud on 2/8/2012 at 2:06pm.

Dear Mr. Brown,

Thanks for your careful reading of my article.

I’d like to respond to your comments, starting with your last one, about high fat dairy and heart disease. You’re correct, the research does not consistently show a link between high fat dairy and heart disease. In fact, some studies find that all dairy, including full-fat, is protective. One theory is that the calcium in dairy is so protective that it overcomes the negative effects of saturated fat. That’s why I chose to highlight this Harvard study, showing that low fat dairy is even more protective. With low fat or non-fat dairy, it seems as though you get the best of both worlds: the benefits of the calcium and vitamin D without the cholesterol-raising effects of the saturated fat.

As you said, in this study the low fat dairy users tended to lead a healthier lifestyle. But the study found that even controlling for lifestyle, low fat milk was still more protective than whole.

As for a low carb diet protecting people from diabetes and high cholesterol, well, the jury’s still out on this. There are many different types of low carb diets, from the cholesterol-raising bacon and steak of the original Atkins plan to some of the leaner versions incorporating fish and chicken. The traditional diets of the Mediterranean and Asia that are linked to low rates of heart disease are not low carbohydrate. But they are rich in fruits and vegetables, have lower levels of saturated fat, and less sugar and refined flour than the typical American diet.

Once again, thanks for reading and for your comments.

Janis Jibrin, M.S., R.D.

Posted by davebrown9 on 2/7/2012 at 1:49pm.

Quoting Janice Jibrin's article, "Researchers speculate that the saturated fat in whole milk may contribute to clogged arteries and obesity—two factors that can increase blood pressure."

Actually, the study says "Women who consumed more low-fat dairy products were older, less likely to smoke and drink alcohol, more likely to be physically active, use multivitamins, and had a higher prevalence of diabetes and hypercholesterolemia...Low-fat dairy intake was also positively associated with fruit and vegetable and whole grain intake and energy-adjusted potassium, fiber, calcium, and vitamin D intake, while inversely associated with red meat intake and cholesterol intake. Women who consumed more high-fat dairy products had generally less favorable lifestyle and diet profile."
http://hyper.ahajournals.org/content/51/4/1073.full

Interestingly, smoking, alcohol, and sedentary behaviour can all increase blood pressure. But apparently a high-fat/ low-carbohydrate lifestyle, which the researchers regard as unhealthy, protects subjects from diabetes and hypercholesterolemia which are associated with increased risk of heart disease. Perhaps slight changes in blood pressure are not as helpful as the researchers imagine.

More recent research (2011) indicates that high dairy fat intake is not associated with heart disease. http://www.eurekalert.org/pub_releases/2011-05/bu-dcd051811.php