Increasing the intensity and frequency of your exercise routine is one way to lose body fat and trim your trouble spots, but it’s not the only way. You can also burn more fat through a metabolic state called ketosis, which is the mechanism behind many low-carb diets, including the ketogenic diet and the Atkins diet. Understanding what ketosis is and learning how to achieve this state can help you whip your body into shape. But before you attempt to achieve ketosis, you should know a few things about the process, including its potential health risks. Ketosis happens when your carbohydrate intake is low. As your body breaks down fat, it produces an acid called ketones or ketone bodies, which becomes your body and brain’s main source of energy. Because ketosis shifts your metabolism and relies on fat for energy, your body can burn fat at a higher rate. Translation? You may reach your weight loss goal sooner than if you didn’t cut carbs at all. If you’re following the keto diet, you will need protein, but you should limit your intake to about 20 percent of your total daily calories. (1) This is important because when you consume more protein than you need, your body converts the excess protein into carbs through a process called gluconeogenesis. This process pushes your body out of ketosis. Another dietary approach that’s gaining popularity nowadays is called intermittent fasting and is based on skipping food for limited, planned periods of time. Intermittent fasting will not put you into ketosis on its own. Some people combine intermittent fasting with a keto diet — but you should know this approach hasn’t been studied or proven to work for weight loss. In addition to following a keto diet, you can talk to your doctor about adding supplements, such as exogenous ketones, to put and help keep your body in ketosis, according to a study from 2017. A normal blood ketone level is under 0.6 millimoles per liter (mmol/L). (2) Any level higher than this can indicate a state of ketosis. Physical signs and symptoms of ketosis include:
Weight lossLoss of appetiteIncreased energy, though energy may be decreased in the first few weeks on the dietFruity-smelling breath (halitosis)Constipation or diarrhea
Many of these symptoms are associated with what people call the “keto flu.” Experts say symptoms should subside within two weeks. With this diet, about 75 percent of your daily calories come from fat, 20 percent from protein, and 5 percent from carbohydrates. Following a typical keto diet food list, you can eat certain foods freely while you’ll need to limit or totally avoid other foods.
Foods to eat on the keto diet include:
Meat, including beef, lamb, pork, poultry, fish, and seafood (preferably wild-caught)EggsCheeseHealthy oils, such as olive oil, avocado oil, or coconut oil (just keep in mind that although coconut oil is permitted on the keto diet, it is linked with raising LDL, or “bad,” cholesterol levels)AvocadosNonstarchy vegetables, like celery, asparagus, leafy greens, cucumber, and zucchiniNuts and seeds
Foods to avoid on the keto diet include:
Grains, such as rice, quinoa, white potatoes, pasta, bread, and pizzaProcessed foodsArtificial sweetenersMilkHigh-carb fruit, including bananas, pineapples, tangerines, and grapesRefined oils
One possible benefit of the ketogenic diet is that you may lose more weight compared with other diets. One study of 17 obese men found that a high-protein, low-carb ketogenic diet over a four-week period helped reduce hunger, resulting in lower food intake and more weight loss compared with a high-protein, medium-carbohydrate nonketogenic diet. (3) But some research exposes the potential health risks of the keto diet. For example, a low-carbohydrate, high-fat diet can be unhealthy due to the risk of increasing bad cholesterol and triglycerides. (8) One study on mice even suggests that eating a low-carbohydrate diet could lead to insulin resistance, increasing the risk for type 2 diabetes. (9) It’s also important to note there have been no long-term studies on the ketogenic diet, nor has there been research that details what may happen to the body if it’s in a constant state of ketosis itself. But given how the body needs carbs to function properly, diets that are based on eliminating or sharply reducing this nutrient while adding fat to your diet may lead to nutritional deficiencies, and supplements and multivitamins are recommended because you’re cutting out entire food groups, warns Alyssa Rothschild, RDN, who is in private practice in Jersey City, New Jersey. Rothschild further explains how following a ketogenic diet for extended periods of time could also lead to osteopenia, which is a precursor to osteoporosis, a disease that’s characterized by bone loss. “When the body is in ketosis, it lowers the blood pH level, causing the blood to become acidic. To counter this, the body takes calcium away from the bones,” she says. “The increased acidity in the body also increases uric acid, which can lead to the formation of kidney stones.” Therefore, it goes without saying that due to the stress that an extremely low-carb diet can have on the body, those with kidney damage shouldn’t try to achieve ketosis or attempt the ketogenic diet. Also worth noting is women who are pregnant or breast-feeding, people on certain diabetes medication and insulin, those with a low body mass index (BMI), children, individuals with gallstones, people who have had their gallbladder removed, (10) and anyone with a history of disordered eating should not try the ketogenic diet. Again, it’s important to note that this state can cause a high level of ketones in the bloodstream, which can make the blood acidic, a dangerous medical state. Everyone’s body responds differently to ketosis. So while some people are able to produce insulin during ketosis to slow down ketone production and avoid a toxic level, others can’t. Ketosis becomes dangerous when blood turns acid. Always speak with your healthcare provider before making any changes to your diet. Because you can reach ketosis by restricting your carb intake, this diet may lower your blood glucose levels naturally. And if you’re overweight and living with diabetes, eating fewer carbs may help you lose excess pounds, which is another way to gain control of your blood glucose. Ketosis is an option for many people with type 2 diabetes because they still produce insulin, which helps their body maintain a safe level of ketones in the blood. If you’re considering trying ketosis or the ketogenic diet with type 2 diabetes, be sure to consult your healthcare provider first to ensure it’s safe for you. This eating approach may interfere with some types of diabetes medication or be inappropriate for you if you have certain diabetes complications, such as kidney damage. Also, achieving ketosis with type 1 diabetes could cause dangerous complications. Therefore, if you have type 1 diabetes, you’ll want to avoid putting your body in ketosis to avoid this potentially life-threatening health emergency. Diabetic ketoacidosis occurs when ketone levels become too high, due to a lack of insulin, and poison the body. This condition can happen to anyone with diabetes, but it is more common in people with type 1 diabetes because their bodies don’t make insulin. In the event that their ketone level rises, their bodies are unable to produce insulin to slow down this production. If left untreated, this condition can lead to a diabetic coma or death. Signs of diabetic ketoacidosis include a high blood glucose level, a high ketone level, dehydration, frequent urination, nausea, difficulty breathing, and dry skin. If you have poorly managed type 1 or type 2 diabetes, test your blood glucose level regularly before and after meals, and make sure you check your ketone level whenever your blood sugar is higher than 240 milligrams per deciliter (mg/dL). (11) A ketone level between 1.6 and 3.0 mmol/L is high and increases the risk of diabetic ketoacidosis. (12) Drinking fluids and taking your insulin can bring down your ketone level. If your level doesn’t decrease or continues to rise, go to the hospital. A ketone level higher than 3.0 mmol/L is a medical emergency. Make sure your carbohydrate intake is 45 to 65 percent of your total daily calories, fat 20 to 35 percent of your total daily calories, and protein 10 to 35 percent of your total daily calories. In other words, if you eat a 2,000-calorie diet, no more than 1,300 of your calories should come from carbs. (13) Before trying to achieve ketosis, be sure you talk to your doctor to make sure your medication or any underlying health issues won’t put you at risk for further health issues or potentially a health emergency.
