You probably know about the ketogenic diet. However, the benefits of ketosis, the best methods for measuring it, and the ideal dietary components of keto may be something you do not know. The keto diet has been around since 1921, when it was developed as a therapeutic diet under certain conditions. Over the last five years, however, interest in addition to its original therapeutic nature has increased.
What is ketosis?
The body is always looking for glucose (and its stored form, glycogen) for fuel. Limiting carbohydrates means limiting the body’s favorite fuel – and therefore it needs to adapt.
The alternative solution is to burn stored fat instead. The metabolic shift from burning glucose to fat produces ketones. Ketones are important because while the body burns fat for energy, the brain does not have the ability to do this. Instead, the brain burns instead of ketones produced by the liver. When the body burns on fat and the brain fuels on ketones, you are in ketosis.
What is the ketogenic diet?
The keto diet is one where you drain your liver glycogen stores and force the body to find the alternative fuel. In addition to limiting carbohydrates to achieve this, it may be necessary to reduce the protein content as well. This is because protein actually has a small insulin-stimulating effect, which suppresses the creation of ketone.
What can you eat on the keto diet?
Achieving ketosis requires a marked reduction in your carbohydrate consumption (ketosis can also be achieved through various forms of fasting). This does not mean that the diet is bacon all the time. Healthy fats, such as avocados and olives, can be key components of the diet in addition to non-starchy vegetables, nuts and seeds and protein sources such as fatty wild fish, eggs and chicken.
Coconut oil and low-fat dairy such as hard cheese may also be included. Recent studies have also found that a more flexible approach (20-50 g of carbohydrates) can still result in ketosis and weight loss and may include more plant-based fiber derived from previously eliminated nuts and non-starchy vegetables. This makes the diet less restrictive and more sustainable over time.
Why is the keto diet bad for you?
While TODAY’s Al Roker is a big fan of the keto diet, the nutrition plan has a fair share of critics. The reality is that any diet can be made unhealthy. The benefit or harm of the keto diet depends on the dietary pattern chosen.
Very low-carbohydrate diets that lack adequate vegetables and other important phytonutrients can harm long-term health, but a keto plan that includes high-fiber plants, healthy fats and moderate protein can be beneficial for weight management and reduce and manage chronic disease.
Constipation can occur, but can be avoided by consuming foods high in fiber. In addition, many individuals will experience what is commonly called “ketoinfluenza”, which are unpleasant symptoms that can occur when the body switches from a carbohydrate to fat burning state. These are short-lived and decrease when the body enters ketosis.
Who is a keto diet good for?
Several benefits are associated with the ketogenic diet. A 2021 study comparing a low-fat diet with a ketogenic diet showed that keto participants had more stable blood sugar and insulin levels despite eating more calories. This is critical as recent data indicates that unstable blood sugar levels may increase appetite and lead to weight gain.
Another study, published in 2020, assessed diets with low carbohydrate intake in older individuals found improvements in body composition, fat distribution, and metabolic health. The diet can also play a role in reducing inflammation, controlling type 2 diabetes and may even help improve cancer treatment.
How do you know when your body is in ketosis?
As a dietitian, I often tell my patients that they do not know what you cannot measure. Increased ketone production is a sure sign of ketosis and can be monitored through respiration, blood and urine, but the accuracy of these methods and the test frequency vary widely.
Since ketones change quite a bit, like blood sugar, it is important to control ketosis levels as they are affected by food and exercise, ideally three to five times a day. Urine strips are the cheapest but least accurate. For accuracy, blood ketone meters or a clinically assisted respiratory ketone device are often the best choice.
Is the keto diet safe?
Studies show that low carb diets can be a safe and effective way for people diagnosed with type 2 diabetes or prediabetes to normalize hemoglobin levels, reducing the risk of hypoglycaemia and helping with weight loss.
However, ketogenic diets are not for everyone and should be avoided by children and teens, people with type 1 diabetes, pregnant people and people with kidney disease, gallbladder, pancreas and liver. It is recommended that you talk to your doctor and work with a registered dietitian before embarking on the ketogenic diet to reduce risks and improve short-term and long-term success for weight loss and health.
Kristin Kirkpatrick consults with various nutrition and diet brands.