There are several ways to test and see if you’re in ketosis. You could use urine test strips, a breathalyzer or even a blood test kit where you prick your finger on a lancet and test you blood.

However, you can always look out for a few signs that will be given off by your body when it’s in ketosis. While it may not be as accurate as a blood test, if you’re following the diet principles correctly and see these signs, it’s safe to assume that you’re in ketosis and just need to carry on what you’re doing to maintain the ketogenic diet.

Bad breath

This is one of the first signs of ketosis. It’s similar to morning breath when you wake up in the morning in a fasted state. What you’ll be smelling is acetone as the body uses ketones for fuel.

Strong sweat smell

If your perspiration and urine have a strong smell, you’re probably in ketosis too. Alongside the acetone released in the breath during ketosis, the body also releases some ketones through the skin’s sweat glands.

Initial decrease in energy

In the initial stages of the keto diet, you’ll feel a lack of energy and lethargy. This is one of the signs that you’re going into ketosis. Your body is adapting to the keto diet and while some people may not experience many side effects, most people will face some issues.

If you’re exercising, you’ll notice that your performance is not up to your usual standards. Ideally, you should rest during the first 4 to 7 days on a keto diet. Give your body time to get used to the diet and make the switch from burning glucose to burning fat for fuel.

Sudden increase in energy

If you suddenly feel like you are more energetic than ever before, you’re most probably keto-adapted and have successfully adopted the diet. Most people who reach ketosis report a sudden increase in energy and mental clarity/cognitive function.

Improved mood and cognitive function

In terms of physical effects, keto improves mood by improving blood sugar control. Keeping your blood sugar at a stable level all day instead of huge spikes and crashes can help keep mood and energy stable.  

In terms of cognitive improvement, before it was a weight-loss diet, keto was a treatment for epilepsy in children. Some kids who don’t respond to any medications can stay seizure-free on keto. Something about a ketogenic diet completely rewires brain energy metabolism – great for kids with epilepsy, but also great for all the rest of us who are interested in better cognitive function and mental health. More and more studies are supporting this.

Digestive issues

Another very common symptom of going into ketosis are digestive issues. You may experience diarrhea or constipation. The body is cleansing itself and this is normal.

You may wish to include some fibrous vegetables such as broccoli in your diet to aid with the process.

Insomnia

One of the most common problems with going on the keto diet is insomnia. It’s also a sign that the body is going into ketosis. This is normal and once you’re adjusted to the keto diet, sleep will usually come easily, and you’ll feel better rested.

Keto flu

Flu like symptoms are common when you’re going into ketosis. Your body is detoxing and getting used to the change in diet. Nothing to panic about. In about 5 or so days, you’ll not experience anymore symptoms. Be sure to stay hydrated and load up on those healthy fats to help mitigate this.

Loss of appetite

The keto diet reduces your appetite. This is especially true when you’re combining it with intermittent fasting. Since your body is now burning fat for fuel (ketosis), it’s much more efficient and can always tap into its fat stores – unlike people who burn glucose for fuel and always need more carbs and food when their glycogen stores are low.

Weight loss

In the first week of the keto diet, you’ll find that you’re urinating frequently. Ketosis causes the body to lose A LOT of water weight. Since you have less glucose in your body, there’s less water retention.

It’s common for people to lose 5 to 10 pounds of water weight in the first week alone. This is one of the most common signs of ketosis.

If you notice that you’re experiencing several of these signs, it’s safe to assume that you’re in ketosis. If you notice any strange or lingering effects, its always a good idea to check with your doctor. And while it is always a good idea to check with your doctor before starting any new diet regimen, this is especially true if you have any underlying health issues.