Why Am I Feeling Tired and Achy When I Just Started Low-Carb?

The Induction Flu, as Dr. Robert Atkins liked to call that flu-like feeling that happens during the first few days on a low-carb diet, was never fully explained under the original Atkins Diet plan. Dr. Atkins just basically told dieters they needed to rest and skip the exercise for at least the first two weeks to gauge how they were going to feel after Induction. Well, the New Atkins Diet has an answer to the Induction Flu and that answer could save you the tired, achy feeling associated with switching your body from burning carbohydrates to burning fat for fuel.

Carbohydrates – The Body’s Primary Fuel Source

Your body loves carbohydrates because they are easy to breakdown and easy to utilize for fuel. When you burn calories walking, talking, sneezing, coughing – you are using carbohydrates. When following the Atkins Diet or other low-carb diet, your body does not have that easy source of fuel, so it has to switch to another source. If you’re following low-carb for weight loss, that fuel source will be fat – but you need to make the switch and that is when the Induction Flu takes over.

Ketosis – The Switch that Controls Weight Loss

Your body only stores about 400 grams of carbohydrates. That accounts for just 1,600 calories. Now, taking into consideration you are following low-carb by the book, you’ll be eating 20 grams of carb per day – that’s another 80 calories. Plus, you’ll be eating protein and fat, usually accounting for more calories than you’d normally intake. All this mumbo jumbo means your body will take two to three days to use up your carbohydrate stores before running out of that easy fuel. You should start feeling the Induction Flu about the third or fourth day as your body is switching over to fat-burning.

IMPORTANT NOTE: If a large portion of your daily calorie intake is coming from protein instead of fat, you may not go into ketosis and your fat burning furnace will not start. Eating too much protein can be detrimental to your weight loss efforts because the body can covert that extra protein to carbohydrates and that’s NOT what you want to happen.

How to Stop the Induction Flu

Here is the key to stopping that achy, fatigued feeling that can last a week or more. Starting your first day on low-carb, drink one cup of broth, two to three times a day. Don’t choose the lower sodium broth, you want all the salt. According to the new Atkins Diet, the salt stops the Induction Flu and I personally have tried this approach and IT WORKS!

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  1. What about feeling achey & fatigued after 3 months on low carb? I've released about 20# and have been reading A LOT and supplementing etc. Still feel achey & fatiqued when I wake up each day.

  2. Hi Annie. There are lots of reasons you may feel achy and I am NOT a doctor, but you may think about adding more potassium. Tuna in oil is a great source of potassium and the oil brings up the fat content so you're following the Atkins protocol of protein/fat perfectly. Look for other proteins that are high in potassium as well. The New Atkins books suggest drinking broth (full salt content) twice a day to ease Induction flu so you may want to try this as well.