Reddit’s Keto FAQs said it best:
What is “keto flu” and how long will I have it?
During the induction phase of a Ketogenic Diet, most people experience a horrid “flu” that often makes people believe from the start that it isn’t right for our bodies. Consider it the first of your many trials to come. The flu is a manifestation of your mental and physical dependence on carbohydrates and the body is essentially going through a phase where it has to learn to use fat as fuel.
Keto flu can be treated by replenishing your electrolytes.
The flu-like symptoms should dissipate in a few days or weeks. But be warned: For as long as you eat low-carb, if you don’t take care to get enough sodium, potassium and magnesium (a.k.a. electrolytes) in your diet, you may experience fatigue, muscle twitching, headaches, muscle cramping, and in severe cases, arrhythmia. Leg cramps may be the most common sign that your electrolytes are out of balance.
How do I replenish electrolytes?
Even if you go out of your way to eat lots of table salt and foods containing potassium and magnesium, you may find you need to take supplements. The minimum daily intake for the three electrolytes is given by Lyle McDonald as:
- 5000 mg of sodium (salt) (http://en.wikipedia.org/wiki/Sodium_chloride)
- 1000 mg of potassium, in the form of potassium chloride or potassium sulfate
- 300 mg of magnesium
You can track the intake of these minerals with a tool such as myfitnesspal.com.
Most of us will not reach these suggested totals with food alone, but there are several ways to ingest extra electrolytes:
- Drink 1 or 2 cups of bouillon or broth daily
- Measure salt and/or salt substitute to add to your food over the course of the day.
- Take a multivitamin containing magnesium and/or potassium
- Take a magnesium supplement.
- Use salt or salt substitute to meet the minimum daily intake, over the course of the day.
- Don’t take large amounts, e.g. >250mg of salt substitute (potassium) at once to avoid adverse effects. Spread it out over the day instead.
- Potassium supplements in capsule/tablet form are limited to 99mg per dose for safety and convenience.
Note: Unfortunately, many potassium-rich foods are not keto-friendly. For example, don’t eat bananas unless you want to get knocked out of keto.
Several companies make low-sodium salt substitutes (LoSalt, Lite Salt, AlsoSalt, etc.) for people trying to reduce their sodium intake. Luckily for keto dieters, these products tend to contain lots of potassium, which we need as a supplement. Read the product label to see how much of which minerals it contains. People with kidney failure, heart failure or diabetes should not use salt substitutes without medical advice, and according to Wikipedia, salt substitutes are contra-indicated for use with several medications.
For scientific references/review that recommends spreading potassium supplementation over the entire day, see p.11 of Opinion of the Scientific Panel on Dietetic Products, Nutrition and Allergies on a request from the Commission related to the Tolerable Upper Intake Level of Potassium – The EFSA Journal (2005) 193, 1-19).
My Personal Defense:
Natural Calm: magnesium
Bullion Cubes: sodium
And I get most of my potassium from lite salt and avocados