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Trying the Keto Diet? Here’s How to Know If You’re in Ketosis

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What are the signs of ketosis? If you're thinking about starting the ketogenic diet, you've probably asked yourself that question. After all, the whole point of following the eating plan is to change the way your body gets energy — and the only way to do that is by getting your body into ketosis.

What is ketosis, exactly?

Ketosis is a state where your body gets energy from fats instead of carbohydrates. While this might seem strange at first, ketosis is a completely natural process initiated by the body in order to help us survive in situations when our food intake is low. Basically, ketosis happens when you don't have enough glucose (sugar) for energy, so your body breaks down the fat instead. Throughout this state, you produce ketones, which are compounds created when fat breaks down in the liver. 

As you might be aware, the keto diet is a low-carb, high-fat eating plan, so people following it are trying to get to ketosis on purpose — it can help keto dieters shed those unwanted pounds. According to Perfect Keto, it can take people anywhere from 48 hours to one week to get into ketosis, depending on your food intake and other lifestyle factors. That said, people who are trying the plan for the first time might not be aware of all the possible symptoms of ketosis. That's why it's always smart to inform yourself ahead of time so that you're prepared.

Possible Signs of Ketosis

It's worth noting that everyone's bodies are different, so people following the keto diet may react to ketosis in different ways. For instance, some folks experience "keto flu" — a loose collection of general symptoms like brain fog and irritability — before they actually reach ketosis. But experts say there are a few general signs you should keep an eye out for when you're trying to figure out if you've officially hit ketosis yet. Unfortunately, not all these side effects are totally pleasant.

According to the Mayo Clinic, some signs of ketosis can include nausea, headaches, and bad breath. The bad breath symptom in particular is so common that some folks even refer to it as "ketosis breath." Experts say another sign of being in ketosis is feeling super drained and exhausted for a short period of time — and then suddenly feeling great out of nowhere. That brings us to the bright side: Feeling less hunger and more satiety and noticing that you're starting to lose weight are also signs that you're in ketosis. Phew! If you've been monitoring your symptoms and you're still not sure whether you're in ketosis yet, you can ask your doctor for a urine test to be sure.

As always, talk to your doctor before starting any new diet or eating plan — especially one as restrictive as the keto diet.

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