Whole Milk vs. Skim Milk

A dear friend and college roommate informed me that her husband recently switched to whole milk because he read that it was healthier. Seeing as this runs contrary to decades of dietary advice, she asked for my opinion on the matter.

Emerging Research on Milk Fat

While saturated fat (the main type of fat in animal foods, including whole milk) is largely considered a dietary villain, emerging research is shedding new light on the dairy debate.

Skim vs Whole Milk

The article in question references a study in which whole milk drinkers were found to weigh less than skim milk drinkers, a surprise, considering a cup of whole milk has nearly double the calories (150 vs 80) of skim milk, due to an additional 8g of total fat (5g saturated fat). However, this is not the first instance of high calorie foods being associated with lower body weights. Nuts and seeds are high in calories, but also high in fiber and heart healthy unsaturated fats, meaning that they fill you up and provide lasting energy. The idea behind both of these paradoxes is that low fat diets are unsatisfying, and often urge us to overcompensate in calories elsewhere. But even though fat is a healthy, essential nutrient, not all fats are created equal.

A recent article from Tricia Ward cites “increasing evidence that dairy fats do not increase [Cardiovascular Disease] risk and may even lead to a better metabolic profile,” due to their unique odd-chain saturated fatty acids. Dairy fats are also shown to be less harmful than margarine, which is a highly processed solid fat made from hydrogenated oils, a manmade process that creates dangerous trans-fats. Additionally, some researchers find that when saturated fats are replaced with refined carbohydrates and added sugars, heart disease risk increases, making saturated fats appear to be a healthy choice.

For these reasons, Dr. Dariush Mozaffarian, the dean of the nutrition school at Tufts University, finds it “absurd” that the school lunch program allows sweetened nonfat chocolate milk, but not whole milk. After all, cutting back on dairy fat means increasing other nutrients, which in the case of added sugar, is certainly a step in the wrong direction.

However, what fails to make headlines in the debate about dairy fat is that when saturated fat is replaced with unsaturated fat in the form of olive oil, sunflower oil, nuts, or avocados, heart disease risk actually decreases. So while butter and milkfat may be dubbed the lesser of two evils (when compared to added sugars), the goal of healthful eating should be to find foods that are proven to actually nourish you and prevent disease, rather than picking foods simply because they are “not as bad as” others. (To learn more about the saturated fat debate, see this blog post.)

Current Recommendations

Fat is an essential nutrient, and health experts generally agree that a low fat or no fat diet is not the answer to health. That being said, reputable nutrition organizations, including the Harvard School of Public Health, the American Heart Association, and the 2015 Dietary Guidelines Advisory Committee all recommend switching from full fat dairy to reduced fat or nonfat dairy, in order to reduce the intake of saturated fats.

As Walter Willett and Frank Hu (of the Harvard School of Public Health) suggest in a recent Boston Globe article, dietary guidelines are (and always will be) a work in progress, based on a consensus of the latest scientific evidence. The emerging research described above (and in Tricia Ward’s article) offers fascinating new insights on the unique role of whole milk and dairy fat, but there is still not enough evidence (nor is there a scientific consensus) for nutrition experts to recommend making a switch to full fat dairy products.

According to the 2015 Dietary Guidelines Advisory Committee report, which was just released on February 19th, “Nutrient intake data, together with nutritional biomarker and health outcomes data indicate that sodium and saturated fat are overconsumed and may pose a public health concern.” The committee “recommend[s] consumption of low-fat and fat-free foods in the Dairy group to ensure intake of these key nutrients while minimizing intake of saturated fat.”

Similarly, these are the recommendations from the Harvard School of Public Health:

Limit your intake of saturated fats by cutting back on red meat and full-fat dairy foods. Try replacing red meat with beans, nuts, poultry, and fish whenever possible, and switching from whole milk and other full-fat dairy foods to lower fat versions, or just eating smaller amounts of full-fat dairy products, such as cheese. Don’t replace red meat with refined carbohydrates (white bread, white rice, potatoes, and the like).

According to NYU nutrition professor and public health expert Marion Nestle, “It isn’t necessary to get into as yet unanswerable questions of heart disease or cancer to decide what to do about dairy foods. The calories and saturated fat are reason enough to choose lower-fat options.”

If there is a general scientific consensus that animal fats should be minimized, then why might journalists suggest that whole milk and butter can keep us trim and healthy? The Harvard School of Public Health offers this explanation:

Many dairy products are high in saturated fats, and a high saturated fat intake is a risk factor for heart disease. And while it’s true that most dairy products are now available in fat-reduced or nonfat options, the saturated fat that’s removed from dairy products is inevitably consumed by someone, often in the form of premium ice cream, butter, or baked goods. Strangely, it’s often the same people who purchase these higher fat products who also purchase the low-fat dairy products, so it’s not clear that they’re making great strides in cutting back on their saturated fat consumption.

Skim Milk vs Whole MilkThe Organic Factor

Whether or not your milk is organic or from grass fed cows can also have a large impact on the nutrition composition of the milk, especially the makeup of the fats. Research shows that whole organic milk from grass-fed cows is a higher (by 62%) in omega-3 fatty acids than conventional whole milk. Omega-3 fatty acids are an essential fat with several documented health benefits, which means that whole milk from organic, grass-fed dairy products may actually offer some modest health benefits not seen in nonfat dairy. (To learn more about why I choose organic dairy, see this blog post.)

The Bottom Line

The research surrounding odd-chain saturated fatty acids (the special kind found in dairy) is still new, so we don’t yet know just how much it differs from other animal fats with regards to health benefits and risks. However, what we do know is that Americans consume too many calories, and too much saturated fat and added sugars. We also know that replacing animal fat with fats from plant sources (like nuts, seeds, avocados, olive oil, sunflower oil, flax, etc.) has been shown to offer all of the health benefits of fat, without the health risks still linked to animal fats.

Food choices are, of course, largely personal. And because all foods offer a mix of different fats, saturated fats are impossible to avoid completely. I choose unsweetened, organic nonfat or reduced fat dairy products (except for flavorful, full fat cheese that I use as a garnish on salads and other dishes), and supplement my diet with an ample amount of fatty plant foods in the form of flaxseed, peanut butter, almonds, avocado, and olive oil. Do you eat dairy products? What kind of milk do you buy?

– Kelly

3 Myths About School Lunch

Providing children with healthy food is a smart investment in our nation’s future, so it’s astounding that there’s room for debate on this issue. As politicians and food giants attempt to roll back the substantial progress made in child nutrition over the past few years, it’s important to examine the strengths and weaknesses of the new school lunch regulations. See below for three of the biggest myths facing the school lunch program today, and to get the facts behind the myth:

Screen Shot 2015-03-03 at 9.32.39 PM

Stereotype American school lunch. image via Sweetgreen

Myth #1: Healthy Regulations are Causing Schools to Lose Money

Critics of the healthy guidelines argue that 50% of School Nutrition Association members expect to lose money this year. However, what doesn’t get reported is that a whopping 65% expected to lose money in 2010, two full years before the healthy regulations took effect. The school lunch program was already a sinking ship, and while the new regulations haven’t completely saved it, they do seem to be helping.

Additionally, Dana Woldow found that this oft-cited 50% statistic is based on shaky data, at best. According to Woldow, “Fewer than 400 district nutrition directors, representing less than 2% of the 25,074 members surveyed, or less than 1% of the total 55,000 membership of SNA, said they expect to operate their meal program in the red this school year.”

When school district food service programs lose money, it is often because of a decline in school lunch participation. However, school lunch participation among students who pay full price (and aren’t eligible for free or reduced priced meals) has been declining since 2007, long before the healthy regulations were implemented. Additionally, this decline has actually started to level off a bit after the 2012-2013 school year.

Screen Shot 2015-03-05 at 8.08.19 PM

Actual lunch served at DCPS: Herb Crusted Tilapia, Whole Wheat Roll, Local Collard Greens, Red Cabbage Cole Slaw, Fresh Banana & Milk  (image via CSPI)

Myth #2: Kids Won’t Eat the New Healthy Lunches

School lunch has been the butt of jokes long before Michelle Obama took to fixing it. And while we all know that washing down chips and candy with a soda is a terrible choice for growing children, especially in a nation plagued with diet-related chronic diseases, the media has been overly sympathetic to critics mourning these changes, as if highly addictive junk foods were actually worthy of defense.

A survey of 557 schools in a variety of school districts found that although many respondents (56%) agreed that students complained about the new lunches at first, most (70%) also agreed that students generally seem to like the new lunches now. This study also revealed a fairly balanced picture of school lunch participation. According to the researchers, “only 4.3% of respondents perceived that ‘‘a lot fewer’’ students were purchasing lunch, whereas 6.2% perceived that ‘‘a lot more’’ were purchasing lunch.”

Studies are also finding that kids aren’t throwing away as much food as critics lead us to believe. A new study evaluated hundreds of lunches in an urban low-income school district both before and after the policy changes. According to the study, students are wasting significantly less food than they were before the healthy regulations went into effect, as kids ate significantly more of their vegetables (from 46% consumption in 2012 to 64% in 2014), entrees (from 71% to 84%), as well as slightly more fruit (from 72% to 74%) and milk (from 54% to 57%). Similarly, a study from the Harvard School of Public Health found a 23% increase in fruit consumption and a 16% increase in vegetable consumption after the new school nutrition guidelines were introduced in 2012. Contrary to popular belief, the study did NOT find a corresponding increase in food waste.

Screen Shot 2015-03-05 at 8.12.50 PM

Actual lunch served at Provo Schools in Utah: Whole Wheat Spaghetti with Homemade Marinara (image via CSPI)

Myth #3: School Lunches Aren’t Nourishing

The school lunch program has been under the microscope for years now, but the truth is that the new school lunches are actually much healthier than home packed ones. In a recent study, researchers analyzed over 1,300 lunches at three schools in rural Virginia. They found that lunches brought from home had more sodium and fewer servings of fruit, vegetables, whole grains and milk. Nearly 90% of the lunches from home also had a sweetened beverage, snack chips and dessert in them. Additionally, while a vocal minority has rallied against the protein caps set for school lunch, packed lunches actually have significantly less protein (as well as less fiber, vitamin A, and calcium). And to top it all off, the study found that lunches from home were more expensive than the school lunch offering at the elementary school level (although not consistently for middle schoolers).

Screen Shot 2015-03-05 at 8.16.16 PM

Actual school lunch: Teriyaki Chicken Rice Bowl with brown rice, steamed fresh carrots, zucchini, yellow squash and Teriyaki chicken. Served with fresh local apple slices, whole grain roll, ice cold milk, an orange, and a fortune cookie. (Image via CSPI)

Want to learn more?

  • This New York Times Magazine article from October 2014 explores the politics of the school lunch program, including the role of corporate lobbying.
  • This February 2015 report from the Union of Concerned Scientists quantifies obesity’s impact on healthcare costs, evaluates the effectiveness of the school lunch program (data was collected before the new guidelines were implemented), and identifies ways to strengthen the school nutrition program.
  • This webpage from the Center for Science in the Public Interest has plenty of infographics, factsheets, policy options, and resources for people trying to promote changes that support healthy lunches.

– Kelly