Food Combining Is The Newest Pinterest-Popular Diet — Does It Work?

From peanut butter and cheese sandwiches to tuna fish and fruit punch, we all have our weird food-combining quirks. But for some people, determining what combination of foods to eat is less about finding an unexpected flavor pairing, and more about strategizing the nutrients they eat together for optimal digestion.

This concept is aptly called "food combining." Although it has roots in Ayurvedic medicine, it's taken off with wellness bloggers who claim these tricks and guidelines can help with bloating, overeating, and even allow you to "detoxify" your body. There are Pinterest-friendly charts that people use to determine which foods you're supposed to eat together or separately, and a bunch of seemingly arbitrary guidelines to follow.

As with any internet-trendy diet or "eating plan" with restrictive rules this might give you some pause. Here's the lowdown on the diet, according to a registered dietitian:

Food combining is an eating method that involves consuming certain macronutrients and foods together, and avoiding other mixtures. The goal is to allegedly reduce the work that your gastrointestinal tract has to do to digest your food. By only eating one food group at a time, and waiting a long time between meals, food combiners claim that you can lose weight and help your gut.

To put it simply, "it makes no physiologic sense that there would be harm in mixing macronutrients together," says Ali Webster, PhD, RD, associate director of nutrition communications at the International Food Information Council Foundation. For starters, our gastrointestinal system is built for multitasking, she says. And, most foods aren’t just made of pure "carbohydrate," "fat," or "protein," they’re a combination of macronutrients, vitamins, minerals and other components, she adds.

It's kind of confusing, but essentially you're supposed choose one category of food (fruit, starch, animal protein, nuts or seeds) to eat per meal, and then stick to non-starchy vegetables.

Per this diet, mixing protein and carbohydrates is bad news, because they digest at different rates. Technically, that's true: protein is absorbed slower than carbs, which are the most readily available source of fuel. "This isn’t a bad thing," Dr. Webster says. "Our bodies have evolved systems for managing different types of foods and nutrients and healthy GI tracts are able to handle whatever is thrown into them." Beyond that, foods are classified into either "acid" or "alkaline," and you're meant to stick to one category during a meal.

"Contrary to what the 'food combining' advocates might think, eating different foods and macronutrients at the same time is actually much more healthful than eating them in isolation," Dr. Webster says. For example, if you ate a high-carb food alone, such as fruit, your blood sugar levels would spike after eating, then rapidly fall, which we know has negative effects on your health. "Eating a meal or snack that includes protein and fiber along with carbohydrates helps to slow glucose absorption, meaning that blood sugar levels won’t spike as high as they would if a person ate carbohydrates alone," she says.

The food-combining diet instructs people to avoid fruits that are high in sugar, and stick to ones that are acidic and less-sugary. As we've said before, the naturally-occurring sugar that's found in fruit isn't something to worry about at all. Oh, and you're only allowed to eat one fresh fruit at a time on an empty stomach. While eating an excessive amount of fruit at once could be a lot of fiber for your body to digest at once, nothing is going to happen to your body if you combine fruits.

These cute and easily shareable charts make it easy to see why the food combining diet has taken off on social media. But here's the thing: if a meal plan requires carrying an in-depth chart around to determine what you "can" and "can't" eat, that's a major red flag that it's probably not worth your time. Diets like this one that label foods as "compliant" or "not compliant" tend to create undue stress that can harm your relationship long-term with food. Listening to your body's cues around hunger and satiety is going to be a way more sustainable approach — not to mention a simpler one, too.

Unless your doctor has instructed you not to eat certain foods together because of specific health conditions, this diet is not a good idea. The human body is highly skilled at digesting multiple foods or nutrients at once; that's why you remain full and satisfied after eating a meal with a variety of balanced nutrients. (Most of us don't eat individual foods one at a time, either.) "Food combinations increase variety, provide a wider swath of nutrient content, and can be more satisfying than eating a single food or macronutrient at a meal," Dr. Webster says.

If you are really concerned about your GI issues, talk to a gastroenterologist or a registered dietitian before you try some diet you found on the internet, Dr. Webster says. "Prolonged issues with food digestion can signal a food intolerance or gastrointestinal conditions like irritable bowel syndrome," she says. "So, it’s important to consult a health professional to get to the root of the problem."