What is the ketogenic diet?
When you think of eating “keto”— short for ketogenic — you should first think of eating a LOT of fat, plus MORE fat, a pinch of carb (roughly 20-50 gm/day), and some protein. What sets this diet apart from others is the effect it has on our metabolism (the way our bodies burn and/or store calories for fuel).
The ketogenic diet forces the body’s metabolism to use fat (ketones) for fuel rather than carbohydrate (glucose). When the body is adequately nourished while in ketosis, we call this “nutritional ketosis”. After approximately 2-4 weeks, the body will become “fat adapted”, meaning it prefers ketones as the primary source of fuel rather than glucose. This is where the many health benefits begin. I like to think of ketones as “high octane fuel” for our bodies, which can reap many health benefits when the diet is followed correctly.
With the ketogenic diet’s rise in popularity, especially as a weight management tool, its touted health benefits have become a highly debatable topic in media and healthcare professionals. This brings about the commonly asked question, “Is the ketogenic diet really healthy?” Let’s let the research do the talking…
The ketogenic diet helps with weight management.
Multiple studies have shown that people on a ketogenic diet tend to lose more weight and keep it off longer than people on low-fat diets. Why is this? Simply put, when excess carbohydrate is ingested, it is turned into fat and stored. However, on a keto diet, not only is this process halted, but the ingested and stored fat is used for fuel!
Also, the keto diet actually revs up our metabolism rather than slowing it down, as shown with other diets focused solely on calorie restriction. Because most of us have plenty of stored fat to burn, plus the fat from our diet, we are able to feel more satiated (full) longer, maintain constant energy, and burn more calories, which in turn may lead to decreased caloric intake and weight loss. Win-win.
Keto eating reduces hunger and/or being hangry.
Is “hangry” (bad temper and irritability in response to hunger) part of your daily vocabulary? If so, you can surely blame the carbs. On a typical diet, your body uses the limited supply of glucose for energy. So, after a few hours of not eating, our blood sugar level begins to drop. This triggers a hormone called insulin to alert our brain to eat again resulting in hunger. If ignored too long, hungry may turn to hangry.
On a fat-fueled diet, there are no significant changes in blood sugar and insulin levels, so hangry doesn’t typically exist. In ketosis, our bodies have a constant supply of fat to burn as fuel, resulting in steadier moods and an increased time one can go between meals. In fact, many people report for the first time, they are more in tune with their true appetite and feel less moody when a meal is delayed or even missed. Often times, people who are fat adapted can go longer between meals, rather than the standard 3-4 hours, which is dictated by a carbohydrate fueled diet.
Keto improves metabolism.
Contrary to many beliefs, weight is NOT just about “calories in and calories out” or “move more, eat less”. Our bodies are much too complex for this simplistic idea. The ratio of macronutrients (fat, carb, protein) that we consume impacts our appetite and our weight. Additionally, many other factors contribute to our ability to burn calories such as hormone imbalance, stress, and insulin resistance.
Did you know that many people on the keto diet do not even count calories? In fact, they may be able to eat significantly more calories while still losing weight effortlessly. In a fat-fueled state, our bodies are able to handle more calories than it can when fueled by carbs.
On a low-fat, calorie-restricted diet, our metabolic rate (how much fuel our bodies need to function) actually drops! Initial weight loss may be seen, but only until the body re-adjusts to functioning at a lower metabolic rate. And unfortunately, studies show that even when calories are no longer restricted, the lower functioning metabolism doesn’t spring back to normal. This means weight loss by restricting calories is regained plus more, because your body figured out how to adapt without having to work as hard—in other words, it got lazy.
The good news? The ketogenic diet has shown no slowing effect on metabolism and actually may increase the rate at which we burn calories, playing a crucial role in improving the success of maintaining weight loss in the long-term.
Keto dieting helps with mental clarity.
Once fat adapted, the previously carbohydrate spoiled brain discovers that fat is awesome! Remember when I said that ketones are like high octane fuel? Ketones are very efficient and highly available as fuel for the brain. Many people have reported increased mental clarity and focus, ability to better stay on task, ample amounts of sustained energy, and decreased “brain fog”.
Ketogenic eating helps fight heart disease.
The ketogenic diet has also shown to significantly improve blood cholesterol and triglyceride levels. HDL cholesterol (known as the “good” cholesterol) is increased, and previously elevated triglycerides usually take a nosedive into healthy levels. There’s a lot of confusion and debate among low carb critics surrounding high-fat diets and its perceived increased effect on LDL – the “bad” cholesterol. LDL cholesterol is not just about the number but the size of the particle (four LDL sizes: large bubbly ones and three smaller ones).
To put it simply, the larger bubbly particles are more protective and the smaller ones, well…less. In a standard cholesterol test, total LDL may appear to increase and misinterpreted as “danger”, but a closer look will often show an increase in the number of large bubbly LDL and less of the smaller ones. In addition, despite what we were once told, intake of foods high in saturated fat and cholesterol are NOT associated with elevated serum cholesterol levels. Saturated fat is not only a healthy fat, it is one of the best sources of fuel for your brain!
Keto helps with Type 2 diabetes and insulin resistance.
This is a big one! There is increasing evidence in the use of the ketogenic diet for the management of Type 2 diabetes and insulin resistance. As an example, think of your insulin as a doorman to deliver the blood sugar out of the bloodstream and into the cell. With insulin resistance, the doorman (insulin) knocks on the cell door, but the cell will not open. The end result? Chronic elevation of blood sugar, which eventually leads to inflammation, diabetes, and metabolic syndrome.
Not surprisingly, on the ketogenic diet, there is almost no sugar to be delivered. As a result, decreased risk of Type 2 diabetes, improved insulin sensitivity, and those with Type 2 diabetes may be able to completely come off of medication, managing by diet alone. Note: anyone on medication for management of diabetes should NOT begin the ketogenic diet until they have spoken first with their doctor so as to safely taper medications and avoid the risk of severe, life-threatening hypoglycemia.
But what about Type 1 diabetes?
According to the most current research, the ketogenic diet may help reduce need for insulin and slow down disease progression, however, it is unlikely to ever completely come off of insulin entirely as the body is unable to produce enough to manage even the small amount of carbohydrate from dietary intake as well as what is produced by the body.
What are other benefits of keto diets?
Below are other areas of research the diet has shown to benefit:
- Brain tumor/cancer
- Chronic inflammation
- Neurological disorders: epilepsy, Parkinson’s, Alzheimer’s, traumatic brain injuries, ALS…
- Mitochondrial disease
- Exercise performance
- Mental health
Who’s at high risk for starting the ketogenic diet?
The ketogenic diet may offer many health benefits as mentioned above…however, dieting is NOT a one-size-fits-all. And although it may be a complete game changer for some, it may not be for others. Below is a list of conditions which may present a higher medical risk. People with these conditions should absolutely talk with their doctor BEFORE starting the ketogenic diet:
- Anyone on medication that would be affected by nutritional ketosis
- Diabetes (Type 1 and Type 2)
- Kidney disorders
- Heart disease
- Any type of metabolic syndrome
- Pregnant or nursing mothers
- Infants and children
- Anyone who has a concern about their health and ability to go on the ketogenic diet
So, is the ketogenic diet healthy and safe?
In general, the answer is yes. However, a healthy ketogenic diet is a well-formulated one. If you think it’s just as simple as not eating carbs…you’ll end up finding yourself in trouble and back on the chronic diet train. Those willing to put in the work, learn, and seek out professional guidance will find keto to be a healthy sustainable lifestyle and not just another failed attempt at dieting.
In a nutshell: The keto diet has been criticized as “unsustainable” and “impractical”; however when done with the right guidance to create a well-formulated, and personalized diet plan, the keto diet becomes a healthy lifestyle rather than just another diet.
Tara Finnerty RDN, CSP, CD—is a ketogenic specialist and fat-fueled enthusiast. Tara is a registered dietitian in Utah and owner of Sugar House Nutrition LLC. Her aim is to provide nutrition support for people wanting to reap the many health benefits of the ketogenic (keto) diet. Her expertise in the keto diet was initially working with children who have uncontrolled epilepsy. Tara supports nutrition diversity and works toward helping people find an individualized approach to make healthy eating sustainable.