The ketogenic or keto diet consists of high fat, moderate protein and very low carbohydrates. People who adhere to a strict keto diet consume less than 50 grams (g) of carbohydrates per day, which forces the body to use fat-derived ketones for energy rather than glucose (sugar) derived from carbohydrates. This condition is called ketosis. It takes an average of two to four days to enter ketosis. To enter ketosis, roughly 70-80% of daily calories need to come from fats, less than 10% from protein, and only 5% from carbohydrates or “carbs.” Intermittent fasting before starting the keto diet can help speed up the process of entering ketosis.
Read on to learn what you need to know about getting into ketosis, the timeline of ketone effects, things you can and can’t eat on the keto diet, signs you’re in ketosis, ways to get into ketosis faster, and the potential risks of staying there. following a strict keto diet for a long time.
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Entering Ketosis: Timeline of Ketone Effects
The human body’s metabolism uses glucose for energy (glycolysis) before using fats. Therefore, before ketosis begins, sugar molecules from carbohydrates stored as glycogen in the body must be exhausted. When there is no stored glycogen (sugar) to burn as fuel, your body enters ketosis as it slowly switches from using glucose for energy to using fat as fuel.
There’s no one-size-fits-all formula for determining exactly how many daily carbs make the difference between whether you enter ketosis or not. However, consuming less than 50 grams of carbohydrates per day is generally considered a ketone-producing diet. Full keto adaptation, in which your body becomes its preferred fuel source during physical activity, can take several weeks or even months.
The ketosis timeline can vary greatly depending on several factors, such as:
- The amount of glycogen stored in reserve when someone starts the keto diet
- Age (younger people enter ketosis faster)
- Body weight
- Exercise Habits
- Basal metabolic rate
Some diseases that affect the thyroid (hypothyroidism) can slow down metabolism and affect how long it takes to get into ketosis. Ketogenic diets may cause a change in the functioning of the thyroid.
Older adults and people with health problems that slow their metabolic rates often take longer to enter ketosis. Be sure to talk to a healthcare professional before starting the ketogenic diet, especially if you have underlying medical conditions.
The exact timeline for fat loss on the keto diet is uncertain and varies from person to person. During the first 24-hour window of the keto diet and the next few days, most of the weight loss comes from water, not fat. Hypothetically, fat loss caused by ketosis kicks in when the body begins burning fat deposits for energy. There is mixed evidence and ongoing debate about the fat-burning superiority of keto diets compared to other weight loss plans.
Getting into ketosis and losing weight on the ketogenic diet is a complex metabolic process; More research is needed to fully understand how it works.
Seeing a Dietitian
If you are considering starting a controlled keto diet at home, talk to a healthcare professional and consult a specialist. registered dietitian (RD) or registered dietitian nutritionist (RDN) before doing a one-day fast or making radical changes to the amount of carbohydrates, fats, or proteins you eat each day.
Signs You’re in Ketosis
Symptoms of ketosis range from flu-like symptoms to “keto breath.” The easiest, science-based way to know if you are in ketosis is with a simple home test using a ketone urine strip. Any color on the ketone test strip (pink to purple) indicates ketosis.
Carbohydrate withdrawal symptoms that may be signs that you’re entering ketosis include:
- Accelerated weight loss
- Halitosis (halitosis)
- Changes in appetite
- Constipation or diarrhea
- Dehydration caused by loss of water in the body
- dizziness
- burnout
- Headache
- irritability
- Gastrointestinal discomfort (stomach problems)
- Ketones in the bloodstream and urine
- muscle cramps
- Muscle Weakness
- Slowness
- Below average exercise performance in the first few days/weeks
Is There a Way to Get into Ketosis Faster?
Fasting for 12 hours is the fastest way to enter ketosis. When you start a very low-carb ketogenic diet, the fewer carbohydrates you eat in the first 24 hours and the next few days, the sooner your glycogen reserves will be depleted and the faster you will enter ketosis.
Medium-chain triglyceride (MCT) oil supplements can help you get into ketosis faster. A 2018 study found keto induction was faster with MCT supplementation. Researchers found that within the first 24-72 hours after starting the keto diet, study participants ate 80% of their calories from fat, 13-17% from protein, and 3-6% from carbohydrates, while also taking in MCT oil. They would enter ketosis faster than people following the same keto diet without taking MCT oil supplements.
Ketosis and the Diet: What’s Safe and Possibly Dangerous?
“Is ketosis dangerous?” It is difficult to answer the question. with scientific precision. Most studies on what is safe and possibly dangerous about ketosis and keto diets are of low quality and do not have large sample sizes.
Due to the lack of sufficient high-quality clinical evidence to show that keto diets are safe and free of potential dangers, there is ongoing debate about whether the benefits of very low-carb ketogenic diets, which are extremely high in unhealthy fats, outweigh the risks.
Overall, available research shows that it is safe to follow a strict keto diet and be in ketosis for approximately 8-12 weeks. After 12 weeks, potential risks and possible dangers tend to increase. Although this topic remains controversial, accumulating evidence suggests that for most people, the long-term health risks of very low-carb ketogenic diets outweigh the benefits.
Long-term negative effects of staying in ketosis for a long time may include:
Research shows that eating a low-carb ketogenic diet during pregnancy increases the risk of neural tube defects in newborns, even when taking folic acid supplements.
Ketogenic diets are generally high in red meat, processed meat, and saturated fat; they are associated with an increased risk of chronic kidney disease, heart disease, atherosclerosis (plaque buildup in the arteries), cancer, diabetes, Alzheimer’s disease, and other diseases. Keto diets are also low in health-protective nutrients such as fruits, vegetables, legumes and whole grains.
Summary
Ketosis is a metabolic state in which your body uses fat as fuel. When someone is not on a ketogenic diet, sugar molecules (glucose) derived from carbohydrates are the body’s preferred energy source. On a strict low-carb keto diet, the body is deprived of carbohydrates, which forces it to convert fat into ketones, which are used as fuel instead of glucose.
It takes an average of two to four days to get into ketosis, because that’s how long it takes for glycogen reserves to be depleted after someone starts eating a keto diet with under 50 grams of carbs per day. Fasting, limiting carbohydrates, and MCT oil supplements can speed up the ketosis timeline.