7 ketosis Symptoms: how to know if you are in ketosis?

by | Last updated: Oct 22, 2020 at 11:49AM | - Published on: Feb 3, 2020

Aside from measuring ketone levels, you may notice a dip in energy as you come off your carb rich diet. Soon thereafter you should start feeling normal again, if not better. In this article we gonna review all symptoms of ketosis. 

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When you first get into ketosis you’re not just starting a new diet, you’re also ending an old one; the standard American diet (SAD) usually. The so-called ketosis symptoms people get when entering nutritional ketosis are actually the unpleasant withdrawal symptoms from coming off SAD. More specifically, these unpleasant withdrawal symptoms occur when coming off any poor dietary pattern stopping you from entering a deep state of fat burning. The ‘keto flu’ is the common name for this adaptation phase and the most known symptoms of ketosis.

You may have heard that people getting into ketosis commonly report more stable energy levels. True. However, some people go through a few days or a couple of weeks where their energy levels initially drop. Then, their body adapts to this low glucose low insulin state, and manages to upregulate fat burning. This then provides stable energy levels. Interestingly, others barely experience the symptoms of ketosis and just effortlessly switch to fat burning!

The keto flu

Whichever of these people you may be, it’s hard to tell if you’re in ketosis if you’re not measuring. Here are some of the signs and ‘symptoms’ suggesting you’ve entered ketosis:

As we said, the keto flu is not really a flu at all, but is more a result of carb withdrawal or temporary electrolyte imbalance. It can cause many symptoms that are similar to the flu, such as fatigue, nausea, headache, insomnia, and diarrhea. The symptoms, however, will differ in kind and severity from person to person. For example, an individual who is transitioning to a ketogenic diet from a very high carb diet will likely experience more severe ketosis symptoms during the keto flu than an individual already following a more moderately low carb diet.

But it’s not all bad news — the keto flu doesn’t last forever. As your body adjusts to fewer carbohydrates, the symptoms will subside and eventually disappear.

7 Symptoms of ketosis

Fruity breath — While bad breath does develop from improper dental hygiene, fruity breath in the case of ketosis comes from increased levels of the ketone body called acetone. When the body is in a state of ketosis, blood acetone levels increase sufficiently for you to breath them out and thus emit its distinctive odor [1]. Breathing ketones aren’t the only way your body excretes ketones, it also secretes them in the urine.

Weight loss — Typically in the first 1-2 weeks of keto, people will drop a significant amount of weight, most of which comes from water. This is because 1 g of carbs (glycogen) is stored with 3 g of water [2]. As you transition to ketosis, maximally full glycogen stores are used up which means the water is also lost and thus lowers your body weight.

Keto rash — The keto rash is a rare side-effect affecting the skin where it gets inflammed lin some individuals who start keto. While there’s not a large body of evidence speculation on why the keto rash develops, studies have shown a correlation between high levels of ketones and its development (which is why it’s also occasionally seen during prolonged fasts). However, the keto rash may also result from other causes such as gut dysbiosis, other dietary factors changing or even the chemical irritation from coming in contact with sensitized skin. The rash presents as itchy red lesions that usually appear on the neck, central chest, upper back, lumbosacral area, and abdomen [3]. It’s not a commonly reported

Frequent urination (or more than normal) — As mentioned with the weight loss, when glycogen stores are depleted, water stored alongside glycogen is released too. When insulin levels drop from an excessive level down to a more normal one – especially following a reduction in dietary carbohydrate intake – water is lost as well as sodium from the kidneys and leads to frequent urination.

Short-term fatigue — Weakness and fatigue are two well-known side effects, as well as two of the biggest problematic symptoms, associated with transitioning to a ketogenic diet. As the body has likely been running on glucose for an extended period of time, it takes the body time to adapt to a new source of fuel, which can take quite a toll on your energy levels. During the adaptation phase, the body also releases electrolytes (e.g. sodium) as already mentioned, which can be a temporary imbalance leading to weakness and fatigue.

Elevated blood ketone levels — Elevated blood ketones! This may seem obvious, but it’s worth emphasizing that the ketogenic diet is the only diet that can be objectively measured to check if someone is in ketosis and to what extent. This is done by looking at blood beta-hydroxybutyrate (BhB) levels. As your body adjusts to burning fat for fuel, it produces ketones that accumulate in the blood and can be quantified using a simple glucose-ketone meter such as the one by KetoMojo. The exact line where ketosis begins is somewhat arbitrary, but generally speaking, it ranges from 0.5 or 1.0 mmol/L, to 3.0 mmol/L and above. Ketone urine test strips are another easy and affordable way to test if you’re in ketosis but their utility is limited.

Digestive issues — Drastic dietary changes may lead to digestive issues in some individuals. Constipation is one of the most common side effects experienced when making the transition to keto, which often results from dehydration. The body absorbs more water from the colon, which causes the contents of the colon to become dryer and harder. To avoid constipation, it’s important to not overdrink, not ‘force it through’ by filling up on fiber, but rather to add in a little sea salt and consume enough healthy dietary fat (e.g. coconut oil, butter, lard, tallow, fatty meats and fish, etc…).

Last word

We’ve covered the transient symptoms (keto-flu) arising from coming off a carb-rich SAD diet (high insulin state) and adopting a ketogenic one (low insulin state). The degree to which a person experiences the keto-flu is highly variable, where some people don’t experience it at all and others struggle with it for a couple of weeks. Much of the keto-flu can be mitigated with a smart electrolyte supplementation strategy and moderating your exercise intensity accordingly.

Written by Raphael Sirtoli, MSc Biology

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