I Keep Seeing Friends Losing Weight With "PFC Every 3," but What Is It?

Mark Macdonald, author of the NY Times bestseller Body Confidence, is the creator of PFC Every 3. PFC stands for the three main macronutrients — protein, fats, and carbs — and eating PFC Every 3 means eating a balance of all three every three hours.

Macdonald said, "eating protein positively affects your blood sugar hormone glucagon (raises your blood sugar), eating carbs affects your blood sugar hormone insulin (lowers your blood sugar), and eating fat slows down the rate of digestion by inhibiting the release of HCL (your stomach's acid). The combination of the three nutrients in the right portion sizes and intervals keeps your blood sugar balanced."

He believes that once your blood sugar levels are balanced, your body will become a "fat-burning machine," because "eating PFC Every 3 triggers the consistent release of your stored fat." You use food to create hormonal balance in the body, and that will help you lose weight, and keep it off, without feeling starving.

Per this diet, you don't need to meticulously count calories or measure portions; just listen to your body. Eat when you're about a five on the hunger scale (not full and not famished). You'll know you've eaten the right amount at each meal or snack because your hunger level will be at a five every three hours.

Registered dietitian Leslie Langevin, MS, author of The Anti-Inflammatory Kitchen Cookbook, told POPSUGAR that most dietitians will tell their clients to pair up meals and snacks with protein, fats, and carbs, allowing three to four hours in between eating.

Langevin added that this balance of macronutrients isn't much different from the USDA's MyPlate model — although for PFC Every 3, the plate is divided into thirds, and Langevin tells clients to "eat half your plate of veggies, one-quarter protein, one-quarter carbs, and use fat in cooking or with foods in the meal like avocado, olive oil, or a little cheese."

Registered dietitian nutritionist and NASM-certified personal trainer Whitney English Tabaie, MS, hadn't heard of PFC Every 3 but agreed with Langevin and said, "Essentially, this describes a normal balanced diet." She always recommends clients aim to get in all three macronutrients at each meal to make sure they're getting all of their essential nutrients. "Eating this way also helps you stay fuller longer and avoid blood sugar spikes by slowing digestion," Tabaie explained.

Langevin added that with PFC Every 3, "overall fat might be higher than normal, but still within healthy recommendations." She thinks one-third of a plate of carbs is great for athletes but is a lot for some trying to lose weight. She suggested breaking your plate up into half low-carb veggies, one-quarter protein, and one-quarter carbs, plus a little fat on top.

"Our bodies are very good at controlling our blood sugars (as long as we do not have insulin resistance or prediabetes/type 2 diabetes)," explained Spencer Nadolsky, MD, a board-certified family and obesity physician with Renaissance Periodization. He said we don't need to eat every three hours, and we don't need to eat all three macronutrients at once, either.

Dr. Nadolsky said that while some people may do well controlling hunger by eating every three hours, "some may do better with fewer meals when it comes to hunger" because eating that often can actually increase hunger. If eating every three hours helps with your hunger and helps you eat fewer calories, then that's fine. "But some do better by spacing out their meals longer, which is why many people find weight-loss success with intermittent fasting."

As far as eating protein, fats, and carbs at every meal and snack, Dr. Nadolsky said, "Some do better eating only two macronutrient types per meal, either protein and fat or protein and carbs. You don't have to have all three."

There is also the crucial point that everyone is different and has different dietary needs. An athlete who's trying to build muscle will need more protein than a person who's not exercising. A long-distance runner will need more carbs than someone who sits at a desk all day. It's important for each individual to figure out their macronutrient needs, and seeing a registered dietitian can help you figure that out.

Like all eating plans, you need to find what works for you. Balancing your macros every time you eat may help ensure you eat the right amounts to give you energy and satiate hunger. Although following this plan and eating every three hours may actually increase your hunger and make you gain weight. You may find that you need more protein than one-third of a plate or that you're hungry every four hours. PFC Every 3 is worth trying, but maybe you'll find success in a modified version. Every body is different, and what works for one person may not work for another.