What's the Deal With Full-Fat vs. Fat-Free?

We've been trained by everyone — our parents, the government, big food, and nutritionists — for years to believe that low-fat is the only way to go. Skim milk, low-fat mozzarella, zero-percent-fat yogurt, light cream cheese . . . you name it! Whole milk was a no-go in healthy households, as was any product with high amounts of fat. But lately, there's been a shift to full-fat dairy . . . why?

"Don't be afraid of all fats!" said Elissa Goodman, holistic nutritionist and lifestyle cleanse expert. She told POPSUGAR that "the outdated mindset that started in the '50s and was perpetuated in the '80s — that high-fat foods are bad and low-fat is good — was based on flawed research."

In fact, recent research shows there might be big benefits if you opt for the original, full-fat, unmodified or processed foods. An early 2016 study of over 3,000 people showed that those who consumed higher-fat dairy had a 46 percent lower risk of getting diabetes. Another recent study (of nearly 20,000 middle-aged women) showed that full-fat dairy may reduce the risk of weight gain and obesity.

Goodman told POPSUGAR that "fat-free foods aren't an upgrade, and the loss of fat has to be made up for in some way. Food manufacturers use refined sugar and salt to add that flavor back in. You're also missing many nutritional benefits by skipping the fat." Registered dietitian Lori Zanini echoed that sentiment, saying, "Many packaged products that are low-fat try to make up for the flavor by adding extra sugar or salt . . . not a great practice."

These modified foods might not be optimal for our bodies. "Foods engineered to be fat-free typically offer no health advantage over those containing fats," said Dina L. Aronson, MS, RDN. "The more important factor is level of processing and what the ingredients are." She advocates for whole, natural foods (and is a proponent of a vegan, dairy-free lifestyle). "Except for people with certain health conditions, there is no need to avoid fats from whole foods," she said. She also noted that the modern shift in food processing has not necessarily been advantageous to our health. "One hundred to 150 years ago, before modern agriculture methods and food processing, most diets worldwide provided omega-6 and omega-3 fats in a ratio of approximately 1:1," which is the optimal ratio for our bodies and can be found in fatty foods. "Changes in the food supply shifted this ratio dramatically — to 10:1 and higher. Such levels have a negative impact on optimal growth and development, cell membrane integrity, and disease risk. And vegans are not necessarily at an advantage, particularly because vegans avoid fish, which is a major food source of omega-3s."

Still, be mindful of the amount of fat in your diet — though the shift has gone away from fat-free, fat still counts toward your day's calories and macros. "The amount of saturated fat in the diet is still a concern, but the data are not consistent regarding the ideal amount, because much depends on the sources and what the rest of the diet looks like — not to mention lifestyle and exercise," said Aronson. "Including reasonable amounts of fat in the diet is healthful and necessary, but overdoing can throw off balance of other nutrients."

Not everyone is a proponent of full-fat dairy and other foods, though. Registered dietitian Julie Upton says, "Unfortunately, a lot of the good news about high-fat dairy foods is based on a lot of shaky science that gets a lot of media attention but doesn't hold up to scientific scrutiny." She warns against full-fat foods as they're higher in calories and can cause weight gain, and says, "If you like the taste of whole milk dairy foods, enjoy them in moderation so you don't exceed your daily saturated fat limit of no more than seven to 10 percent of your total calories or about 20 grams per day for most women."

Jessica Flanigan, AIP (autoimmune Paleo) nutritionist, says, "The full-fat vs. low-fat question generally is too broad of a question for my crowd, and it almost always comes down to the individual. I long ago threw out that any one diet works for everyone." She looks at each client's blood chemistry as well as other factors to determine how well an individual digests fat, but in terms of her favorite fat sources, she loves "olive oil, cultured ghee, and coconut oil."

And it goes without saying (we hope) that when making any major changes to your diet, speak with your doctor, nutritionist, or both to ensure you're making the best decision for your unique makeup, metabolism, and digestion.