The Ketogenic Diet: Eat more fat to lose fat?
Fat is an Essential Nutrient
For the past couple decades, low-fat has ruled supreme in the diet industry. You can walk into any grocery store and find countless ‘low-fat’ products that claim to be ‘healthy’ and ideal for weight loss. And, yes, it’s true that many of these products are low-calorie, and for many years, restricted caloric intake has been widely accepted as a necessity for maintaining a ‘healthy’ weight.
But we are only now beginning to understand that fat loss is so much more complicated than ‘calories in, calories out’. And recently, research has been demonstrating that fat, which we have for so long believed to be the enemy of fat loss, may actually be quite good for our health—and our weight. The old logic that ‘eating fat = being fat’ has been proven deeply problematic and, in most cases, incredibly inaccurate. Just as eating spinach will not make you green, the fat in a sirloin steak will not directly transplant itself upon your midsection. This is not how to the body works.
It seems that we as a society have forgotten that fat is an essential nutrient; meaning that we need it to survive. A severe lack of fat in our diet will impair cognitive function (our brains are made up of nearly 60% fat!), our heart health, our reproductive system, our skin, our lungs–the list goes on. And as experts in scientific fields are discussing the importance of fat and its role in our health, the fitness community is following suit. Enter, the ketogenic diet.
What is a Ketogenic Diet?
So, what is a ketogenic diet? First of all, there isn’t only one ketogenic diet; there exist multiple variations with varying protocols and objectives. But it is the process of ketosis—the breakdown of fats to produce energy–that all ketogenic diets share: including the ketogenic diets for fitness and fat loss that have recently become so popular.
While your body can take energy from multiple sources, carbohydrates are the most accessible and easily processed. When your body lacks carbohydrates, it turns to fat for the energy it needs—and that includes both the fat in your avocado and in your cells–and this process is called ketosis. That being said, not all low-carb diets will necessarily result in ketosis—though low-carb diets may still benefit you in for your health and fitness goals.
BUT! A very important disclaimer: beware of exogenous ketones. You might see on your pharmacy shelves ‘raspberry ketones’ or other types of ketones in a pill or liquid form. They might claim to aid in fatty acid metabolism, or increase your basal metabolic rate, and generally to aid in fat loss. Reputable fitness and health experts agree that the ketosis produced by supplementing with exogenous ketones (ketones not produced in your body) are ineffective and, in many cases, can be counterproductive and detrimental to your health. When you supplement with ketones, you are effectively telling your body to stop producing its own ketones, thus slowing down any weight loss efforts: the exact opposite effect of what ketone supplements claim to perform.
An effective ketogenic diet will deplete your body of carbs, forcing it to burn ketone bodies to avoid draining your muscles of their protein stores. Many fit individuals might be wary of a high-fat diet; however, fat, though high in caloric density, slows down your body’s absorption of nutrients, which leads to greater and longer satiety. And studies have shown that individuals on a restricted-carbohydrate, ketogenic diet for weight loss demonstrate greater–and longer lasting!–results than individuals on a restricted-fat diet. What is it about ketogenic diets that can explain these results?
What is it about ketogenic diets that can explain these results?
- Ketosis suppresses your appetite: one scientific review found that individuals on ketogenic, low-carbohydrate and calorie-restricted diets were less hungry and experienced a lessened desire to eat, in comparison to individuals on moderate-carbohydrate, calorie-restricted diets. Another study found that individuals on a calorie-restricted diet demonstrated lowered levels of ghrelin (the hormone that signals the feeling of hunger) when they were in a ketotic state.
- A ketogenic diet preserves your muscle mass while torching fat. Studies have found that the catabolism of lean body mass is reduced by ketone bodies–in short, when following a very low-carbohydrate or restricted calorie diet, ketones will preserve lean tissue. Your body in ketosis prefers to burn fat, rather than muscle. That being said, any diet that does not provide enough calories for your body’s optimal functioning will be catabolic–meaning, it will lead eventually to the breakdown of muscle.
- The ketogenic diet has been shown to increase insulin sensitivity.
- There is some evidence to suggest that a ketogenic diet will increase your thermogenic and metabolic rate; thus, your body will burn more calories while at rest.
Introducing the Ketogenic Diet Into Your Life
So, how should you go about introducing the ketogenic diet into your life? We at Infofit recommend always that you speak to your physician, a nutritionist, or a qualified elite personal trainer before making any dietary changes. With that being said, there are some general guidelines that we can recommend to anyone considering the ‘keto’ lifestyle.
- Eat to your macronutrients. Most keto diets for fat loss suggest a macronutrient breakdown of 60-70% fat, 15-20% protein, and 10-15% carbohydrates.
- Drinks lots and lots of water! It is absolutely essential that you stay hydrated, as ketosis has been shown to have a diuretic effect. And, because you’ll be ingesting less carbs and, most likely, less fiber, adequate levels of hydration will help to prevent constipation and digestive complaints.
- Try some fasting for added fat burn–intermittent fasting and exercise can both briefly shift the body into a ketogenic state.
- Be brief! For most, there is no need to commit to a ketogenic diet indefinitely. The ketogenic diet can be intensive and lead to feelings of deprivation if maintained for too long–and it shouldn’t take long to see results! One study found that a ketogenic protocol followed by a Mediterranean-style maintenance diet resulted in long-term weight loss success. Again, speak to a qualified healthcare professional to find out if the keto diet is right for you and your goals.
If you remain unconvinced, ketogenic diets have been shown to demonstrate myriad health benefits beyond fat loss, including increased cognitive function, the prevention of Alzheimer’s and epileptic seizures, a lessening of chronic inflammation, and a decreased risk of cancer. It’s time to bring fat back into your fitness!
Written by Theresa Faulder, Master’s in English, Certified Personal Trainer (completing) and Infofit fitness blog writer.
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