Many people have a hard time wrapping their heads around ketogenic diets or simply known as keto diets. We get it, it seems contradictory on the surface … I can eat all the fatty foods I want — even bacon — and drop tons of body fat? That makes no sense!
Yet for many people, “going keto” has delivered rapid weight loss. Question is, is it healthy weight loss? And is keto the right dietary path for the gym-goer looking to shed body fat without losing muscle and strength gains? Our resident nutrition expert tackles these issues to help you decide.
Featured Expert:Susan Lopez, RD, CSSD, LD, is a tactical performance dietitian who specializes in working with athletes from the military, firefighter, police, and first responders. Lopez is a military veteran and special operations spouse whose unique experience and knowledge help elite warfighters and community heroes stay fit and healthy. She is also the team dietitian for Bravo Sierra.
The body is such a complex organism and amazing in its ability to adapt to whatever we humans like to throw at ourselves.
The body has different metabolic pathways that can be used to supply energy to our cells. Each macronutrient (protein, fat, carbs) can be used to make energy, although the body’s preferred source of energy is carbohydrates. The least preferred method of energy production in the body is through the breakdown of proteins into amino acids, which are then converted to glucose through the process of gluconeogenesis. If your body is having to break down proteins for energy production, it’s likely that your nutrition needs some help.
Fat can be oxidized in the body to produce energy, and in a rested state a healthy individual will do a fairly good job of utilizing fat for energy production. And yes, eating more fat in the absence of adequate carbohydrates will increase fat metabolism. But, just because you’re metabolizing fat doesn’t mean that you aren’t still storing fat. And if your rate of fat storage is higher than your rate of fat burn, you will get fatter.
Just as calories taken in need to be lower than calories out in order to lose weight, so too does fat storage need to be lower than fat oxidation in order to lose fat. You’ll likely need to be in a calorie deficit to lose fat as well.
In diets such as keto, the increased intake of nutrient dense foods and decreased intake of overprocessed or calorie dense foods can create a calorie deficit, even though calories from fat may be higher, and this often leads to fat and weight loss. There’s also no conclusive evidence that a low-carbohydrate diet is any more beneficial than a low-fat diet when calorie restriction is applied.
So, how do I know if my rate of fat oxidation is greater than my rate of fat storage (or vice versa)? Is it just a matter of tracking my weight loss and/or my body fat levels?
In a real-world setting, yes — there really is only the physical changes that can be tracked.
Do you recommend tracking calories when following keto? Most people who do keto seem to only track carbs without paying attention to calories.
Yes and no. When first starting with a low-carb diet, it’s OK to just track one macronutrient to keep it simple. This is likely to create a natural calorie deficit, particularly if that person’s diet was higher in ultraprocessed foods beforehand. However, it’s possible that someone who eats fairly “clean” already may need to track calories to ensure that a calorie deficit is present for weight and/or fat loss.
Will eating more fat ruin my health? How do I follow a low-carb, high-fat diet and stay healthy?
A diet that’s higher in saturated fat may have an effect on lipid levels. That said, the body needs some saturated fat to function optimally. What’s more important is the ratio of unsaturated to saturated fat in the diet, intake of heart protective fats such as Omega-3s, and overall fiber intake.
A lot of keto diets say to moderate protein to stay in ketosis. What’s your recommendation for protein intake for someone who’s trying to lose weight on a super-low-carb, higher fat diet?
In a true ketogenic diet, the recommendation is to take in less than 20% of calories from protein. The reason for this is because amino acids (the building blocks of protein) can be used to create glucose in a process called gluconeogenesis. When this occurs, it can affect ketone production. However, protein intake is often fat-loss friendly because it provides benefits outside of just muscle protein synthesis. It’s satiating, helpful for blood sugar balance, and is necessary for many hormonal functions and overall cellular health.
The recommended protein intake for active individuals according to the International Society of Sports Nutrition is 1.2 to 2.0 grams per kilogram (2.2 pounds) of bodyweight per day, with intakes of up to 3.0 grams per kilogram per day considered safe. (Converting to pounds, a range of 1.2 to 3.0 grams per kilogram would be roughly 110 to 270 grams of protein for a 200-pound individual.) In a calorie deficit, it may be beneficial for muscle mass retention to be on the higher end of those recommendations, particularly on a low-carb diet.
