Are you familiar with the term ketogenic? In the last few years this has become an increasingly popular nutrition approach used by some for health, weight loss and other reasons. Below is a quick overview on whether this approach will work for you depending on what your goals are.
[caption id="attachment_5228" align="aligncenter" width="300"] A ketogenic diet. 5% carbohydrate. 20% protein. 75 % fat.
First of all, we should probably define what we mean by a ketogenic diet. This is a nutritional approach that uses a high fat, low fat mix of macros that was initially developed to treat children with epilepsy. Basically when the body experiences a fast glucose levels drops. A particular hormone HSL, hormone sensitive lipase, increases and helps breakdown fat.
What Is the Breakdown of Macros?
As for the specific mix of carbs, fats and proteins, we're talking about 5% carbs, 75% fat and 20% protein. If these number don't mean too much to you consider that in the literature a VLCD (very low carbohydrate diet) is 40% of calories from carbohydrate. This is 8X the carbs that you would eat on a ketogenic diet. Another way of looking at it is that athletes may sometimes get as much as 70% of the calories from carbohydrates.
So this is a vastly different approach from the various other 'low carb' approaches or performance nutrition recommendations.
How Much Protein?
In terms of protein, we sometimes hear more is better. And the more meathead you are the more you beat your chest and reach for another steak or chicken breast. On a ketogenic diet it's important to keep protein to the 20% threshold because anymore can lead to gluconeogenesis. This is the metabolic process where protein is broken down into its amino acids and then reassembled to make new glucose.
When we're talking about eating 75% of our calories from fat this means foods like butters, oils (coconut & olive), fish, avocado, nuts and seeds.
In terms of the carbohydrates this means eliminating starches such as grains, cereals, pastas, breads, potatoes and most fruits. There is an allowance for small doses of some berries.
How Long Does This Take?
So how long does it take to reap the rewards of ketosis? The induction phase, or where the body becomes fat-adapted, can take 1-2 weeks. And just as it varies in terms of healing time for an injury or to get over the flu so too the range can get stretched a little bit.
If we were able to give a ketogenic diet a go what can someone expect in term of fat loss, health and performance benefits?
Let's take a brief look at each of these.
Fat Loss - This is the #1 reason people go to the gym and look to make a nutritional change. Sure, it's great to reap all the health benefits as well but for most people it's about fat loss. And a ketogenic diet definitely helps with weight loss.
Did you see what I did there? I specifically said weight loss, and not fat loss. Almost everyone who starts on this approach will notice a smaller number on the scale in the first week. And that can be a great thing and really help some continue with the changes they are making.
But honestly in one week the loss of weight is most likely not due to a loss of fat stores. Each gram of carbohydrate we consume requires 3 grams of water to metabolize it. If someone eats 100 grams fewer carbs in a day. This is the amount of carbs in two pieces of whole wheat bread or a cup of long-grain rice. So not a huge consumption of carbs.
When the diet is changed to eliminate these foods we lose the 100 grams of carbs plus the 300 grams of water that goes with it. 454 grams makes a pound so we can see how after a week it's reasonable to see someone drop 5-7 pounds.
If you measure lean body mass and fat mass you probably won't notice a change.
Health & Disease - This is where a ketogenic diet probably makes the most sense. With the origins tracing back to the Mayo Clinic and treating kids with epilepsy there has been more research showing the benefits on metabolic syndrome (diabetes), alzheimer's and cancer. Most cancers tend to rely on a high anaerobic metabolism. The higher the intensity of exercise the more reliance there is on glycogen as a fuel source. I would guess a ketogenic diet impairs the fuel supply to the cancer cells and thus shows to be effective in that way.
But besides the fuel source a ketogenic diet may be a benefit for health and disease is that it helps decrease oxidative stress, it increases antioxidants and scavenges free radicals.
Performance - If you are an endurance athlete a ketogenic diet could work for you. At this point I'm not entirely convinced it's a superior approach than fueling with carbohydrate. Our good friend and trusted dietitian, Dr Susan Kleiner, says that even the athletes that claim to be low carb are still using carbs during various points in training or competition. Again this is for a very niche spectrum of endurance athletes. This definitely wouldn't be recommended for any athletes that have a high anaerobic energy system demands. Think of MMA athletes, basketball players and soccer players that have have brief bursts of all-out activity.
To put this in perspective we can look ATP resynthesis for a fat-adapted keto athlete versus one that is carb-fed and uses glycogen to fuel performance. A carb-fed athlete will be able to generate ATP 2.5-5 times faster than a keto athlete.
Other Things to Consider
Sustainable - Whenever a client is considering making a change to their health we ask them if it is healthy and sustainable? In this case I'm not sure how sustainable eating 75% of your calories as fat is for most people? This requires discipline and some food knowledge. And even if an individual is committed to the program and knows what foods to choose it gets a little harder when they travel. Have you ever looked to order food on a plane or at an airport? The offerings tend to be carbohydrate rich and with too much protein to fit the appropriate macros required. Never mind trying to eat 75% of your calories as fat.
The Dangerous Middle - The interesting thing about carbs and fats is that they can be readily used as fuel sources. Which one we use depends on availability and intensity. If we eliminate carbs to 5% and do low intensity exercise a ketogenic approach can work. However, as we showed above, 50 grams of carbohydrates per day is very low. This is a sandwich, or some oatmeal or a half cup of rice. It's not a lot. And there are carbs in everything.
The potential danger could be that we are getting a huge supply of fat that if carbs are too high this may prevent us reaching a state of ketosis. Hormone sensitive lipase is not stimulated. We don't reap the reward of extra fat burning. And we store the extra fuel as fat.
It's not hard to see this could be a problem for many. A piece of birthday cake at work. Some popcorn at the movies. An extra beer or a corn on the cob at a BBQ. This are all normal activities that would push us well above the 50 grams of carbs per day.
Quality Matters - What matters more...the quality of the food you eat or how much you eat? Well, the obvious answer is that both matter. And we can't separate the two and approach our health with only one of these in mind. I remember meeting with a potential client at one time. This client had a fat loss goal. And they ate nothing but the best quality foods. Lean proteins, tons of veggies, adequate fiber and enough water. But upon deeper inspection this person was eating around 3800 calories a day when they should have been closer 2300. Over eat by 1500 calories, regardless of the quality, and you will gain mass.
My concern is that some will view a ketogenic diet as a free pass to get more of their calories through a window. A cheese-burger sans-bun with bacon, mayo and some avocado. The next day could be a bun-less hot dog at Costco followed up with some sugar-free pudding.
And I should distinguish that my take on it is that there's a difference between making a burger at home andordering one at your favourite fast food outlet. At home you can control the quality, freshness and size of the meal. You get to control how the burger is prepared and what ingredients are used. At home you can cook and eat the most nutritious coconut and olive oils. And at home you can eat the meal as soon as it prepared and in the freshest state.
Eating out takes a lot of this control away from. Is the beef in a fast food burger better quality than what you'd buy? Is it prepared with the same quality ingredients you would use? Do these use the same quality oils you do at home? Is the serving size based on what you need or what most people demand and expect?
Here's the thing...I have nothing against fast food. Whenever I go to California I like to make a trip to In N Out Burger. But that is the exception and not the rule. But for the most part I feel I can prepare a healthier option at home than what a fast food restaurant can deliver.
Fiber - A number of people don't like eat vegetables. And some don't care for fruit either. As soon as you limit your intake on carb intake to 5% you are limiting the opportunity to get fiber in the diet. When you consider some of the best sources of fiber including beans, whole grains, brown rice, popcorn, potatoes and cereals are banned on a ketogenic diet you can see how this could become a problem.
The Take Home Message
A ketogenic diet may be beneficial for certain populations. Those that would benefit the most are people looking to improve their health. They'll see improvements in their blood sugar readings, A1C and cholesterol. Those with epilepsy, Alzheimer's and cancer may notice improvements in their symptoms and health.
As a fat loss strategy this will help people drop pounds in the first few weeks. And this can be a great thing to help kick start a healthier lifestyle. In the long term it's not as promising and appears to work best in combination with exercise.
Lastly, with athletes this would work best for long-distance, endurance athletes. I wouldn't consider it for any sport with an anaerobic emphasis. If you do consider dabbling with a veto approach try it in training first and make notes in your training journal so you've got some numbers to evaluate the effectiveness.