Within the past few years, fasting has become a phenomenon. And intermittent fasting was something that was taking the world over with such speed! In fact it was Google’s most researched diet in 2019,
and its popularity continues to grow. One common way to practice intermittent fasting is through time-restricted eating. It means you are limiting the amount of time in a day you can eat. But while that definitely proved to be extremely beneficial for some, it wasn’t really the kind of regime that worked on others. So here’s something that might actually be working for you. Have you heard about dirty fasting?
By Aleem Shah
T his newer type of time-restricted eating that’s catching on: dirty fasting. Here’s my take on the trend, and how you can determine if dirty fasting may be right for you or not. So to be able to understand dirty fasting, you first must understand how it works. It is a new approach in which more calories, or certain foods, are allowed during the fasting window. The goal? To disrupt the concept of fasting as little as possible but while achieving similar benefits as a clean fast. The practice is referred to as “dirty fasting.” There is no human clinical research on the health benefits of dirty fasting, but some people who do it claim that the approach does provide similar benefits as clean fasting. Fasting has long been understood as the absence of calories. But there’s an emerging concept that redefines what it means to achieve a state of physiologic or molecular fasting—basically, when your cells aren’t impacted in the same way they likely are during a “fed” state—that may allow for dirty fasting to still be considered a form of “fasting.”
The rules of dirty fasting differ depending on who you ask. Some websites that promote dirty fasting say that any food or beverage during the fasting hours is fine, as long as it’s less than 100 calories. Other sites only sanction high-fat foods, which don’t immediately spike insulin. Some allow artificial sweeteners because they’re zero calories, but research shows these sweeteners may increase insulin levels during a fast, even when tasted and not swallowed. Other followers of dirty fasting OK higher-protein foods, like bone broth or collagen, during the fasting window. Many people who are interested in dirty fasting seek the health benefits of time-restricted eating but with the flexibility to be able to eat or drink something with calories during the fasting window. Proponents of dirty fasting say that flexibility helps them stay on track with their fasting routine because they’re not as limited or as hungry.
The one human study available on dirty fasting was able to shed some light on the diet’s effectiveness. That randomized, controlled trail was conducted in 105 adults who were assigned to either water only, a traditional breakfast, or a nutrient bar after a 15-hour overnight fast. Participants had their blood glucose and ketone levels measured every hour for four hours after consuming each of the options. Researchers found that the nutrient group had glucose levels comparable to that of the water-only group throughout the hours after the meal and ketone levels that were similar to the water-only group two or more hours after the meal. In contrast, the breakfast meal spiked glucose and reduced ketones. One of the appeals of time-restricted eating is that, in addition to weight loss, the practice may offer bonus health benefits. However, experts point out that the quality of what you eat during non-fasted hours (or the small dirty fasting allowances) matters—a lot. That is, nutrition is still key. Be sure to build in a variety of veggies, fruits, and other whole foods daily to optimize your intake of vitamins, minerals, fiber, antioxidants, and macronutrients. For both weight management and health, the ultimate goal is to settle into a routine that’s sustainable long term. Intermittent fasting or time-restricted eating is about striking a balance between restricting and nourishing, not just the former. If dirty fasting feels like a healthier compromise for you, it may be the best approach for your lifestyle and relationship with food.