Your Ultimate Guide to Ketosis

Ketosis is a metabolic state that happens when your body shifts from using glucose for energy in favor of ketone bodies. The result is often weight loss, but there are several research-backed benefits to ketosis beyond the scale. 

There are also quite a few misconceptions about what ketosis actually does in the body, its long-term effects, and whether following a ketogenic diet to boost ketosis is safe for most. We explore all of this to demystify the process behind the diet. 

What Is Ketosis?

Ketosis is a natural process in which your body uses stored fat for energy over glucose. This happens in the absence of carbohydrates (generally, due to periods of fasting or eating a very low-carb diet).

During ketosis, the levels of beta-hydroxybutyrate (BHB) ketones in your blood increase to 0.5-3 millimoles per liter (mmol/L). (1)

This range is ideal for experiencing weight loss, but the purpose of changing your diet to trigger ketosis depends on your health and wellness needs. Being in ketosis is also linked to improved mental clarity, better energy levels, and therapeutic applications, particularly for metabolic syndromes. (2)

Relation to the Ketogenic Diet

The keto diet is designed to stimulate ketosis. It helps your body use high levels of ketones as an alternative fuel source by reducing carb intake to 30-50 grams per day. The very low-carbohydrate diet is a high-fat diet and moderate in protein to ensure you’re meeting health and energy requirements. 

Standard keto diet macros look like this:

• 5-10% carbohydrates
• 30-35% protein
• 55-60% fat

On a very low-carb diet, increased ketones serve as your primary fuel source, resulting in a number of ketosis health benefits.

Note: Ketosis Is Not the Same as Ketoacidosis

The difference between ketosis and ketoacidosis comes down to health risks. Ketosis is a natural metabolic process. Ketoacidosis, also known as diabetic ketoacidosis (DKA), is a life-threatening medical emergency.

While both states involve ketone production, ketone levels during ketoacidosis increase to dangerous levels on top of very high blood sugar.

Ketoacidosis is a complication primarily affecting individuals with type 1 diabetes, but it can also affect type 2 diabetes patients. (3) Having an illness or infection can also increase the risk of ketoacidosis.

Entering Ketosis

Limiting carb consumption to 20-50 grams or less net carbs per day will likely result in ketosis and ketones in 3-4 days. However, that time can vary depending on your metabolism, physical activity levels, fasting history, sleep, and chronic stress. For instance, the more often you enter ketosis, the faster your body is likely to transition.

Testing your ketone levels is a good way to understand how your body will react to changes in diet and lifestyle to bring about ketosis.

How do I know when I am in ketosis? An increase in ketones is the best way to know that you’re in ketosis. You can test your ketones using a blood ketone meter, urine test strip, or breath acetone meter. Blood monitors are the most reliable as they directly measure blood ketone levels via BHB, the most abundant ketone.

What Can Help

Reaching ketosis can be done using different strategies, but for the most part, it involves lowering your carbohydrate intake to 50 grams or less each day.

The easiest way to meet this carb requirement is to focus on non-starchy vegetables and fruits, eliminating higher-carb foods like bread, pasta, rice, desserts, and the like. Broccoli, Brussels sprouts, spinach, cucumber, avocados, berries, and melons are all great plant foods with lower carbohydrate content.

But don’t forget the healthy fats! Your body (with the exception of your brain) can derive energy from dietary fatty acids when you don’t consume carbs, and consuming plenty of fats will help you transition more quickly into ketosis.

What foods should I eat to get into ketosis? Since most meats and seafood have next to zero or zero carbs, you can have them in abundance. Animal-based foods are healthy sources of fat that can keep you satiated as you reduce carbs.

Exercise is another useful tool to enter ketosis. The longer and more intense the workout, the sooner your glycogen stores become depleted. If you feel fatigued from cutting carbs, try a brisk walk or yoga. As soon as you feel better, resume your usual workouts.

Intermittent fasting can also speed up ketosis and boost weight loss. (4)

Related: 30 Best Keto Snacks: Ideas and Recipes

Symptoms You May Experience

What are the signs and symptoms of ketosis? Temporary signs and symptoms of ketosis typically occur within a few days of reducing carbs. These include:

• Bad breath: “Keto breath” is often described as fruity-smelling or resembling nail polish remover. Acetone, an ingredient in polish remover, increases in your body during ketosis.
• Weight loss: A low-carb diet can lead to rapid weight loss in the short term. This is mostly water weight in the first couple of weeks, as carbs can cause water retention. More gradual fat loss happens in the long term.
• Fatigue: Tiredness is a common complaint as your body switches from glucose to ketones for energy. You can reduce this by taking electrolytes and exogenous ketones.
• Digestive issues: You may experience diarrhea caused by a high fat intake. Constipation can result from reduced fiber.
• Insomnia: Interrupted sleep can happen shortly after reducing carbs. Gradual carb reduction, eating carbs later in the day, and electrolyte supplementation can help.
• Sore muscles and headaches: Fewer carbs cause your body to flush out more water and lose electrolytes like sodium and potassium. This can lead to body aches, cramps, and headaches.
• Decreased athletic performance: Removing carbs from your diet will deplete your muscle glycogen stores, which may lead to decreased performance in the gym.
• Loss of alcohol tolerance: When you deplete glycogen stores, you’ll also lose most of your alcohol tolerance. Most people in ketosis begin to feel a slight buzz after fewer than a single alcoholic drink.
• Sugar cravings: Being highly dependent on carbs in the past may trigger intense cravings when you remove them. In the long run, the keto diet may actually reduce food cravings.

What ketosis feels like at the start is collectively called the keto flu because of the resemblance to flu symptoms. (5) Although they’re almost inevitable, these discomforts resolve on their own and can be successfully managed through optimal nutrient intake, hydration, and rest.

10 Benefits of Ketosis

There are a number of research-backed byproducts and benefits of keto beyond what’s happening as your body burns fat stores. And not all of them are weight-related! These include:

• Weight loss and management: The most commonly cited benefit of ketosis is weight management. People with blood sugar conditions (like PCOS and diabetes) who often struggle to lose weight via calorie counting or portion control find that keto can support body fat loss. This happens, in part, because ketogenic diets affect appetite by preventing an increase in ghrelin, a hormone produced by the stomach that regulates hunger. (6) When comparing low-carb and low-fat diets, studies show that low-carb groups end up losing more weight.
• Fewer seizures: Studies show that ketones can have significant anti-seizure effects in those diagnosed with epilepsy. (7) Exogenous ketone supplements may also provide some benefits in addition to a keto diet.
• Better diabetes management: Those with type 2 diabetes may be able to return glucose levels to the non-diabetes range using nutritional ketosis. (8) It’s important to work with a qualified health professional who can help you monitor ketones and blood sugar.
• Reduced risk of heart disease: The ketogenic diet may have a positive effect on blood pressure and other markers of cardiovascular disease. (9) The anti-inflammatory effects of keto support better heart outcomes, too.
• Lower inflammation: Chronic inflammation affects everything from stress levels to your risk of chronic medical conditions. Ketones may also alleviate symptoms of chronic inflammatory conditions like arthritis, but more research is needed. (10)
• Improved clarity and focus: Ketones provide a stable and efficient source of energy for the brain. That can enhance cognitive function, improve long-term concentration, and reduce brain fog. (11)
• Better skin health: The anti-inflammatory effects of the state of ketosis show promise as a treatment for skin conditions like acne, psoriasis, and eczema. (12)
• Neuroprotective effects: Research shows the production of ketones may play a role in reducing your risk of neurodegenerative diseases like Alzheimer’s. (13) We need more research, but one theory is that ketosis provides an efficient energy source for brain cells.
• Improved endurance: While cutting carbs may make you feel tired initially, you eventually reach keto-adaptation. This happens when your body acclimates to using ketones as its main fuel. 
• Better cancer management: While studies are still in the animal phase, early research shows ketosis may inhibit tumor cell growth in those with cancer. One study showed cancer cells cannot use ketones for energy. (14)

Is it good (for your body) to be in ketosis? Being in ketosis can be beneficial for those looking to lose weight, improve mental clarity, and boost energy levels. As with any new diet, it’s essential to get medical advice from your healthcare professional before starting keto. 

Possible Risks + Side Effects

Symptoms of the keto flu are the most common ketosis side effects. These typically go away after a few weeks to a month of consistency with keto. 

Less common side effects and potential dangers of ketosis include the following:

• Hypotension: Abnormally low blood pressure can occur if a person with hypertension takes blood pressure-lowering medication while going low-carb. 
• Hypoglycemia: Abnormally low blood glucose can occur when you’re avoiding carbs while taking insulin and other medications for blood sugar levels. (15)
• High cholesterol: While many people see a change in their cholesterol levels for the positive, some may see an increase in their low-density lipoprotein (LDL) cholesterol. (16)
• Kidney stones: Some studies show an increase in kidney stone risk in keto dieters. (17) Reduce your risk by supplementing with potassium citrate to reduce acids in the body.
• Nutrient deficiency: If you fail to replace high-carb, nutrient-dense foods with low-carb versions, you may develop nutritional deficiencies. 

What’s great about filling up on meat and seafood is that they’re some of the most nutrient-rich foods available. Drizzle those with healthy fats like olive oil, and you’re doing even better by your body. Once you’re beyond the keto flu, you should be feeling better than you did before.

In most cases, ketosis is safe and beneficial for preventing and managing health conditions, but it requires medical attention. You can stay in ketosis safely for as long as a healthcare professional supervises it.

This is particularly important in type 2 diabetes patients. Diabetes requires monitoring of blood glucose and insulin levels to prevent diabetic ketoacidosis. Talk to your doctor or dietitian about a blood glucose level chart for ketosis and managing your condition using keto.

The Takeaway  

Ketosis is a natural process that has several benefits for long-term metabolism health, and the healthiest way to reach ketosis is to follow a keto diet. Sign up for our email list to get updates and discounts on products to make doing keto easier!

Read Next: Your Ultimate Guide to the Mediterranean Keto Diet

17 References