Clean vs. Dirty Keto
The ketogenic diet has helped countless people who have struggled with managing their weight. But it is a diet that has now been split into two different diets: one diet’s been around for over 100 years; the other is a new spin for modern eating habits: How do you decide whether eating clean versus dirty keto is the right diet for you? Compared to the Standard American Diet (SAD), clean keto is not only used to help people lose weight, recent studies have also demonstrated it hosts a variety of health benefits that don’t include weight loss: Clean keto can help increase energy levels, promote brain function, and support athletic performance—for both professionals and amateurs alike.1 Those who have experienced the benefits of clean keto are understandably curious about the latest version of the diet, known as “dirty keto,” and how it holds up against eating clean. Let’s take a closer look.
Keeping it clean
The clean keto diet is based on the idea that eating a fixed macronutrient breakdown of mostly healthy fats, high-quality protein in moderation, and restricted carbohydrates (less than 50 grams per day) provides your body with the fuel you need to lose body fat without hunger, weakness, and fatigue.2 The reduction in carb intake puts your body into a metabolic state called “nutritional ketosis.”3 During this nutritional ketosis, your body no longer relies on glucose as a primary energy source. Instead, your liver converts fat into ketones–which are a great source of fuel for both your body and brain. Ketones also increase the brain-derived neurotrophic factor (BDNF), which works to support your brain’s existing neurons while encouraging new neuron and synapse growth.4
On the clean keto diet, you get most of your calories from healthy fats found in foods like avocados, grass-fed butter, olives, olive oil, coconut oil, nuts, and seeds. However, keep in mind that some nuts and seeds are better than others. You’ll want to choose those that are high in fats and lower in carbs; brazil nuts, almonds, walnuts, chia seeds and flaxseed are all good options. You can also eat all of the nonstarchy, leafy vegetables you want, as well as other low-carb vegetables like broccoli, peppers, cauliflower, green beans, asparagus, cucumber, and zucchini. In moderation, eat protein in the form of grass-fed meats, pasture-raised poultry, cage-free eggs, and wild-caught fish. Finally, if you want to reach for something sweet, 90% dark chocolate is your best option.
On the list of what not to eat? For starters, remember that the clean keto diet restricts the intake of carbohydrates to achieve a shift from glucose to ketones as a primary fuel source. In order to avoid food high in carbs, limit fruit consumption—as it’s higher in sugar content–and forego fruit juice altogether. You should also avoid grains or starches such as rice or pasta, beans or legumes, root vegetables, and any low-fat or diet products, as they are typically highly processed and high in carbs.
Let’s talk dirty (keto)
Dirty keto follows the same macronutrient breakdown of fats, protein, and carbs as clean keto, with one major difference: It doesn’t matter which foods those macros come from. That is to say, on the dirty keto diet, instead of choosing good fats, like wild-caught salmon, grass-fed butter, and avocado, you eat a fast-food burger (without the bun), processed cheese, and pork rinds.
Can you lose weight by following the dirty keto diet? Possibly. But the benefits halt there—and there are remarkable health drawbacks from the dirty keto diet that you should be aware of, too. For starters, this keto diet is missing vital micronutrients like vitamins, minerals, and enzymes that are necessary to your overall health. Furthermore, processed foods are usually high in sodium, which can lead to bloating and inflammation. You’re also more likely to regain the weight you lost and experience more cravings and less satiety. Dirty keto foods can trigger these cravings, bloating, and feelings of withdrawal which are symptoms commonly associated with what is known as the “keto flu.”
You are what you feed your brain
In a healthy digestive system, the cells that form the paper-thin lining of the small and large intestines are packed very closely together. In fact, they’re so close that under normal, healthy conditions, only digested food (solutes) and water—can and should—enter the bloodstream. But when there is intestinal inflammation or inappropriate dietary intake, the tight junctions of the gut lining can easily be disrupted and become too porous. Diets high in chemical-laden processed foods—such as those often consumed on the dirty keto diet—can damage the gut lining and force it to become more permeable. These same factors also affect the balance of both the trillions of beneficial and harmful bacteria in the gut. When this balance is disturbed, harmful bacteria can get the upper hand and cause an increase in gut permeability.
The result is intestinal hyperpermeability, or “leaky gut.” This condition can allow toxins, bacteria, undigested food particles, and other undesirable gut contents to enter the bloodstream and circulate to the rest of the body, including your brain. Not only does your gut affect your mental state in how you feel physically, but the reverse is also true: Your mental state affects your gut and gut health. This makes following the clean keto diet a better choice for your brain’s health.
While dirty keto follows the same macronutrient breakdown as clean keto, there are marked differences in the two diets and their respective impacts on the body (and brain). A dirty keto meal can be a placeholder while you’re in a pinch, but it shouldn’t be part of an ongoing healthy eating regimen. Instead, by following a clean keto diet, you’ll not only find success losing weight and gaining energy, but you’ll also provide your brain with longer-lasting, healthier fuel.
- Volek S et al. Euro J Sport Sci 2015;15(1):13-20.
- Volek JS et al. Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutr Met. 2004;1:13.
- JAMA. 2018;319(3):215-17.
- Adapted from 1) Neuropharmacology of the ketogenic diet; 2) Neuroprotective and disease-modifying effects of the ketogenic diet – NCBI.
Dr. Silverman is a paid consultant and guest writer for Metagenics.