Keto flu, sometimes called carb flu, can last anywhere from a few days to a few weeks. Metabolic changes happening within as your body weans itself from burning glucose for energy may result in heightened feelings of lethargy, irritability, muscle soreness, light-headedness or brain fog, change in bowel movements, nausea, stomachaches, and trouble focusing and concentrating. I know, it sounds terrible, and probably vaguely familiar. Yes, these are all common symptoms of the flu, hence the name.
The good news is this is a temporary phase as your body adjusts, and it doesn’t affect everyone. Factors causing these symptoms include an imbalance of electrolytes (sodium, potassium, magnesium, and calcium) and sugar withdrawal from the significantly decreased carbohydrate consumption. Expecting these possible symptoms means you can be prepared to alleviate them and decrease the length of keto flu, should it occur at all.
Sodium levels are directly affected by the amount of highly processed foods you consume. To clarify, everything we eat is technically a processed food; the term means “a series of steps performed to achieve a particular end.” Even cooking at home from scratch requires the act of processing food. Relating to our current culture, though, where ready-to-eat foods are at every turn of the supermarket, these highly processed foods tend to contain exorbitant levels of hidden salt (sodium is a preservative as well as a flavor enhancer).
Adhering to a keto diet is most successful when you’re doing the actual cooking, and you can control the number of carbs and amount of sugars in a dish. Home cooking tends to be less processed, which might also result in lower sodium. Increasing the amount of salt in your food and drinking a homemade stock such as the bone broth, are easy, natural ways to boost your sodium levels.
Below are other foods to focus on during your keto phase-in period. They’re naturally rich in magnesium, potassium, and calcium to help keep your electrolytes in balance.
Magnesium (helps with muscle soreness and leg cramps)
Avocados, broccoli, fish, kale, almonds, pumpkin seeds, spinach
Potassium (helps with muscle soreness, hydration)
Asparagus, avocados, Brussels sprouts, salmon, tomatoes, leafy greens
Calcium (especially important if you were a big milk drinker pre-keto)
Almonds, bok choy, broccoli, cheese, collard greens, spinach, sardines, sesame and chia seeds
Another way to lessen the chances of experiencing keto flu is to begin slowly decreasing your carb intake a few weeks before starting the 4-Week Plan. It can be as simple as swapping your morning muffin for a hard-boiled or scrambled egg, skipping the bun and wrapping your burger in lettuce (often referred to as protein-style when ordering), or swapping out spaghetti for zoodles. This way, when you dive into the plan it’ll feel more like a natural progression in eating fewer carbs than a sharp right turn in your diet.
Let’s cut to the chase here. Bad breath stinks, literally, but it’s something you should brace yourself for when switching to keto. There are two thoughts as to why this occurs.
As your body enters ketosis and begins releasing ketones (a by-product of burning fat for fuel), one of the ketones released is acetone (yes, the same solvent found in nail polish remover and paint thinners). Acetone is excreted through urine and from your breath in the body’s attempt to finish the metabolic process of breaking down those fatty acids. This can result in unpleasant-smelling breath.
Protein can also be a factor in contributing to keto breath. Remember, the macronutrient goal is high fat, moderate protein, and low carb. People often think high fat is interchangeable with high protein. That is far from true. The body digests fat and protein differently. Our bodies produce ammonia when breaking down protein and usually release it during urine output. Eating more protein than you need results in the indigestible amount lingering in your gut system, where it ferments, producing ammonia, which is then released through your breath.
The upside is that keto breath is a good indicator your body is in ketosis. How long the smell lasts varies according to how well your body adapts to ketosis. Many sources indicate it lasts anywhere from one week to just under a month. A deeper dig through keto message boards and chat groups shows it can persist for months, while some people report never experiencing it. Some solutions to possibly avoid or lessen keto breath are to always be armed with sugar-free gum, reduce your protein intake, make sure you stick to a good dental routine (brushing and flossing), and follow the advice mentioned earlier on gradually reducing your carbohydrate intake before jumping full steam ahead into the 4-Week Plan.