Heard of dirty Keto? It’s slang for a ketogenic diet that ignores food quality.
Dirty Keto is when you order a greasy burger, remove the bun, and call it dinner. Dirty Keto is also when your plate has nothing green on it.
The opposite of dirty Keto is ‘clean’ Keto. On a ‘clean’ Keto diet, you get most of your energy from nutrient-dense whole foods.
If you care about your long-term health, it’s important to differentiate between the two. That’s what we’ll be doing today.
What Is Dirty Keto?
Dirty Keto is not a precise term. In general, it describes a ketogenic diet that’s high in ultra-processed foods like vegetable oils, artificial sweeteners, and processed meats and low in nutrients like vitamins, minerals, and fiber.
Dirty Keto is a type of ketogenic diet. Like other forms of Keto, it entails consuming around 55-75% of your calories from fat, 15-35% from protein, and less than 10% from carbohydrates.
For all its bad press, a dirty Keto diet still follows the main rule of Keto dieting: it keeps carbs low. Keeping carbs low keeps insulin low,facilitating the breakdown and release of stored body fat.[*] In other words, a dirty Keto diet can promote the fat-burning state called ketosis.
Weight Loss on Dirty Keto
Most studies on Keto don’t focus on food quality when structuring ketogenic diets for participants. Instead, they focus on how carb restriction affects a variety of health outcomes.
Some potential Keto-related health benefits include:
- Fat loss and weight loss in both obese and non-obese populations.[*][*]
- Reversing type 2 diabetes.[*]
- Inflammation control.[*]
- Hunger control.[*][*]
- Potential therapy for neurodegenerative diseases and cancer.[*][*]
Let’s expand on weight loss for a moment, because it’s a primary reason folks go Keto. Can a dirty Keto diet help someone lose weight?
Perhaps. The mechanisms by which Keto promotes weight loss are largely independent of food quality.
For instance, low insulin facilitates fat burning, especially the burning of visceral belly fat.[*] And you don’t need to eat whole foods to keep insulin low. You just need to restrict carbs.
Lowering carbs can also curb your appetite. Keeping carbs low reduces spikes and dips in blood sugar, so you aren’t crashing, listless, and hangry at 4 PM. A Keto diet has also been shown to lower the hunger hormone ghrelin.[*]
But dirty Keto isn’t the best way to capture these benefits.
Drawbacks of Dirty Keto
Dirty Keto is called dirty Keto for a reason. It’s a sub-optimal way to eat. Here’s why.
#1: Inflammatory vegetable oils
On a Keto diet, you consume most of your calories from fat. The type of fat, however, is up to you.
A dirty Keto diet leans heavily into a group of fats known as vegetable oils. These oils include soybean oil, safflower oil, sunflower oil, peanut oil, cottonseed oil, corn oil, and canola oil.
Veggie oils are high in an omega-6 polyunsaturated fat (PUFA) called linoleic acid. While small portions of linoleic acid are healthy, excess consumption of this PUFA, researchers believe, is a key driver of the American obesity epidemic.[*]
Why? Because consuming too much linoleic acid creates inflammatory conditions that drive fat storage. This has been shown in mice.[*]
Cooking with vegetable oils is dangerous too. At high heat, the fragile PUFAs oxidize, creating compounds called oxidized lipids linked to heart disease.[*]
#2: Micronutrient deficiency
If your Keto plate is devoid of low-carb vegetables, you’re probably not getting enough vitamins and minerals.
Non-starchy veggies like spinach, kale, asparagus, broccoli, and cabbage are some of the most nutrient-dense foods around. These plant foods are rich in folate, vitamin A, vitamin C, calcium, magnesium, potassium, and a variety of phytonutrients with health benefits researchers are still unraveling.
Take folate, for example. This B vitamin (vitamin B9) is crucial for energy production, nervous system health, cardiovascular support, and reproductive health.[*]
The best natural sources of folate are lentils, but lentils have too many carbs to be Keto. That leaves Keto folks with spinach, asparagus, beef liver, and broccoli. Unfortunately, a dirty Keto diet spurns these foods.
And that’s just folate. How many other vitamin and mineral deficiencies would occur on dirty Keto? How many health problems would result from these deficiencies? Best not to find out.
#3: Lack of fiber
If you don’t eat vegetables on Keto, you won’t get much fiber into your system. Digestive consequences may follow.
Since fiber helps with bowel regularity, avoiding this indigestible carbohydrate can lead to constipation. Avoiding fiber may also negatively impact your gut microbiome.
Fiber is indigestible through normal routes, but it is digestible by gut bacteria.[*] When gut bacteria digest fiber (especially soluble fiber) they produce anti-inflammatory compounds like butyrate. Not something you want to miss out on.
