How to know you are in ketosis and potential side effects of a keto diet
How do you know if you are in ketosis? It is possible to measure it by testing urine, blood, or breath samples. But there are also telltale symptoms that require no testing:
- Dry mouth and increased thirst: Unless you drink enough water and get enough electrolytes like sodium, you may feel a dry mouth. Try a cup of bouillon or two daily, plus as much water as you need. You may also feel a metallic taste in your mouth.
- Increased urination: A ketone body, acetoacetate, may end up in the urine. This makes it possible to test for ketosis using urine strips. It also – at least when starting out – can result in having to go to the bathroom more often. This may be the main cause of the increased thirst (above).
- Keto breath: This is due to a ketone body called acetone escaping via our breath. It can make a person’s breath smell “fruity,” or similar to nail polish remover. This smell can sometimes also come from sweat, when working out. It’s often temporary.
Other, less specific but more positive signs include:
- Reduced hunger: Many people experience a marked reduction in hunger on a keto diet. In fact, many people feel great when they eat just once or twice a day and may automatically end up doing a form of intermittent fasting. This saves time and money, while also speeding up weight loss.
- Possibly increased energy: After a few days of feeling tired (the “keto flu”) many people experience a clear increase in energy levels. This can also be experienced as clear thinking, a lack of “brain fog,” or even a sense of euphoria.
Potential side effects of a keto diet
When you suddenly switch your body’s metabolism from burning carbs (glucose) to fat and ketones, you may have some side effects as your body gets used to its new fuel, especially during days two through five.
Symptoms may include headache, tiredness, muscle fatigue, cramping, and heart palpitations. These side effects are short-term for most people, and there are ways to minimize or cure them (see below).
To reduce potential side effects, you may decide to gradually decrease your consumption of carbs over a few weeks. But with a slower start you’ll likely not see results as quickly. While the short-term results may differ, the long-term results should remain the same.
We recommend you stop sugar and starches all at once. You will likely lose several pounds within days. While much of the initial rapid weight loss is water weight (from reduced swelling), it is still a highly motivating way to start your keto journey.
Most people who start a ketogenic diet will experience some symptoms of the “keto flu.” This is what you may feel, more or less, a few days after you have started a keto diet:
- Light nausea
- Difficulty focusing (“brain fog”)
- Lack of motivation
These initial symptoms often disappear within a week or two, as your body adapts to increased fat burning.
The main cause of the keto flu is that carb-rich foods can result in water retention (swelling) in the body. When you start a low-carb diet much of this excess fluid is lost. You may notice increased urination, and with that some extra salt is lost too.
Before your body adapts, this can result in dehydration and a lack of salt. These appear to be behind most of the symptoms of the keto flu.
You can reduce or even eliminate these symptoms by making sure you get enough water and salt. One simple way to do this is to drink a cup of bouillon or broth, once or twice a day.
How much weight will I lose on a keto diet?
Results vary widely. Most people lose 2-4 pounds (1-2 kg) during the first week. This is mainly water weight. After that, it’s common to lose about 1 pound (0.5 kg) of excess weight per week. However, some lose much faster (often younger men), some a bit slower (often women over 40).
When you approach your normal body weight, the weight loss will slow. Just remember, a “normal” body weight differs from person to person depending on our genetics and environmental exposures and may not fit what we see in the popular media. The weight loss will not go on forever. If you follow the advice to eat when you are hungry, you will eventually stabilize your weight.
What happens after I reach my health and weight goals on a keto diet?
Once you reach your goals you can either keep eating keto (to maintain the effect), or you can try adding a bit more carbs. In the latter case the effect of the keto diet will be slightly weaker, and you may or may not regain some weight.
If you revert to your old habits, you’ll slowly return to the weight and health situation you had before. It’s like exercising – if you stop doing it, you’ll slowly lose the benefits. As you may expect, a keto diet, like exercise, only works when you do it.