Beyond the Barn: Dairy Nutrition – What the Cows Give Back to Us

We spend a lot of time thinking about how we can optimize the nutrition of our dairy calves and cows.  But do we spend that much time thinking about how we can enrich our own diets with nutritious dairy products?

As we wrap up American Heart Month, let’s spend a few minutes reviewing dairy’s role in a healthy lifestyle.

Nine essential nutrients
The Dietary Guidelines for Americans recommends three servings of low-fat or fat-free dairy products per day.  That’s because milk and other dairy products are good sources of the following nine essential nutrients.  The percent Daily Value provided in one serving of fat-free milk is noted in parentheses.

• Calcium (30%):  In addition to building and maintaining bones and teeth, calcium is important for nerve function, muscle contraction and blood clotting.
• Vitamin D (25%):  The body needs vitamin D to promote absorption of calcium and enhance bone mineralization.
• Protein (16%):  Animal sources of protein, such as milk, are referred to as perfect or complete proteins because they contain all 10 essential amino acids (amino acids that humans cannot produce in their own bodies), which are the building blocks of muscle tissue.
• Potassium (11%):  This mineral helps maintain blood pressure and regulates muscle activity and contraction.
• Vitamin A (10%):  Vitamin A protects skin and eye health.  It also regulates cell growth and the immune system.
• Vitamin B12 (22%):  This vitamin builds red blood cells, which carry oxygen from the lungs to muscles.
• Riboflavin (26%):  Riboflavin plays a critical role in our bodies as it helps convert food into energy.
• Niacin (10%):  Niacin is a part of many of the enzymes found in our body, which help to metabolize sugars and fats.
• Phosphorus (25%):  This mineral helps strengthen bones and generates energy in body cells.

Heart health
A report issued by the Dairy Research Institute shows that diets with two to three servings of low-fat dairy foods have had positive effects on blood pressure in adults and children.  The 2010 Dietary Guidelines for Americans reports that moderate evidence shows consumption of milk is associated with reduced risk of cardiovascular disease.

Bone health
On average, Americans are eating only about half of the dairy servings they should in a day.  As mentioned above, dairy products are an excellent source of calcium, phosphorus and vitamin D, all of which contribute to bone health.  Osteoporosis is a condition in which bones become weak and brittle, commonly resulting in fractures to the wrist, hip or spine.  Research shows that consumption of dairy products – especially by children and adolescents in their peak bone-growing years – can help reduce risk of osteoporosis later in life.

Healthy weight
The National Health and Nutrition Examination Survey reports that an estimated 66 percent of adults are either overweight or obese and 31.9 percent of children ages 2 to 19 are in the 85th percentile of the BMI-for-age growth chart.  This is a concern as excess body weight increases the risk of heart disease, hypertension, type 2 diabetes, certain types of cancer, and other diseases.  Several studies suggest that dairy foods may play a beneficial role in maintain a healthy weight because they are nutrient-dense.

Women’s health
Studies show dairy products reduce risk of several women’s health issues:

• Research at Penn State University suggests that women who consume their three servings of milk each day may increase the availability of folate contained in other foods.  Folate, a vitamin, may help prevent heart disease and stroke.  It is also essential in preventing birth defects, such as spina bifida.
• Findings from the Nurses’ Health Study II report that women who consume the most calcium-rich foods had the lowest risk of forming kidney stones over eight years.  In contrast, taking supplemental calcium did not have an impact on kidney stone formation.
• A study published in The American Journal of Clinical Nutrition showed that women who ate fermented milk products, such as yogurt, three or more times a week had a 79-percent lower incidence of urinary tract infections than those who ate those foods once a week or less.