Starting a Keto diet can come with a few unexpected side effects. While many people prepare for the Keto flu, far fewer expect to develop an itchy skin condition known as Keto rash. 

If you’ve noticed an itchy red rash after starting Keto, Carnivore, or Fasting, you may be wondering what in the world is going on. The good news is that Keto rash is usually temporary and improves as your body adapts. 

What is Keto rash?

Keto rash, known medically as prurigo pigmentosa, is an inflammatory skin condition associated with ketosis. Ketosis is the metabolic state in which your body shifts from relying primarily on glucose to burning stored fat for energy. 

Not everyone who starts a Ketogenic diet gets Keto rash. However, when it does occur, it often develops soon after the body has switched into ketosis, leaving people uncomfortable, and wondering whether they should continue the diet. 

What does Keto rash look like?

Keto rash usually begins as small, itchy red bumps or patches. It most often appears on the:

• Chest

• Upper back

• Neck

• Shoulders

• Under the breasts

The rash often appears on both sides of the body in a fairly symmetrical pattern. After the inflammation settles down, it may leave behind darker patches of skin that fade over time. 

What causes Keto rash?

Researchers still don’t know exactly why Keto rash develops, and there is likely more than one factor involved. 

One leading theory suggests that ketone bodies may trigger inflammation around tiny blood vessels in the skin. Another proposes that the body’s rapid metabolic shift, while adapting to ketosis, creates a temporary inflammatory response. 

Another possibility is simply detox. Toxins stored in fat cells may be released into the bloodstream during fat loss, which could contribute to skin irritation. Although this idea has not been proven, it remains one of several possible explanations. 

Heat, sweating, and friction from clothing may further irritate the affected skin and make the itching feel worse. 

While we don’t know the exact cause of Keto rash, we do know what it is not: Keto rash is not caused by food allergies or poor hygiene. 

Who is most likely to get Keto rash?

Keto rash seems to be most common in people who enter ketosis quickly, or those who are very new to a Ketogenic diet, or Fasting. This includes those who are:

• Starting a Ketogenic diet

• Following a very low-carb or Carnivore diet

• Doing Extended Fasting 

• Losing weight rapidly

Fortunately, only a small percentage of people in ketosis develop the rash. 

Will it go away?

For most people, yes. Keto rash often improves within a few weeks as the body adapts. Some people are able to return to ketosis later without the rash coming back. Everyone responds differently, so patience is definitely part of the process. In the meantime, there are some things that can help.

Tips to help manage Keto rash

While there isn’t a guaranteed cure, there are things you can do to help reduce discomfort:

• Drink plenty of water. This will help flush toxins, and your skin will feel better when you’re well hydrated. 

• Take electrolyte supplements, especially if you’re doing Extended Fasting. While electrolytes won’t fix Keto rash, balanced electrolytes support overall skin health and help you adapt to the Ketogenic diet. 

• Wear loose, breathable clothing to reduce friction, and try to stay cool, since excessive heat and sweating can make itching worse. 

• Avoid scratching as much as possible. Scratching only makes the itch worse, and increases your risk of infection. 

• Take care of your skin. Even though Keto rash isn’t caused by poor hygiene, gently cleansing and moisturising your skin daily is always a good idea. 

• If all else fails and the rash is severe, consider temporarily increasing carbohydrate intake, enough to reduce ketosis and help the rash resolve. 

Important: Please note that many skin conditions can look similar, and many medical conditions can cause rashes. If your rash is spreading rapidly, painful, or accompanied by fever or other concerning symptoms, don’t assume it’s just Keto rash. It’s always best to check in with your healthcare provider. 

It does get better

Keto rash is no fun, but it’s usually temporary. Hydrate well, take your electrolytes, and try to stay as comfortable as you can until it clears up.