Ketogenic Diets and Intermittent Fasting are pretty hot in the street right now and for very legitimate reason. These two diet strategies combined are a fat burning super team. They go together like Jordan and Pippen, Many people have asking me about what it is and how it works...
“Not eating breakfast, don’t you do something like that?”
A lot of people are using intermittent fasting as a method of weight loss, despite this going against the old theory of eating 5 to 6 small meals per day. The 5 to 6 meals per day theory is designed for elite athletes who work out for many, many hours.
The problem is that every time you eat you are spiking your glucose and insulin levels, which will store in the muscles first and then the fat second. So, for an athlete working out 6 hours per day this method works, but for the vast majority of us who are not working out 6+ hours per day, this type of repeated insulin spike puts your body into a fat storing mode.
So, the less times you spike insulin the better, right? Right. You accomplish this by eating less meals. 2 huge meals within a 6 hour window as opposed to 6 small meals throughout the day.
Let’s breakdown the science behind this a bit…
Insulin, is the key to it all. It can affect people differently, but insulin, above all, is an energy storing hormone. It signals the body to store energy, either as glycogen for stressed muscles (post workout) or as stored FAT. In abundant quantities inslin will blocks leptin signals to the brain.
What’s leptin? Leptin is a hormone that is secreted from the fat cells and tells your brain when you’ve stored enough, aka when you’ve had enough to eat. (1)
To sum it up so far… spiked insulin tells your body to store fat and eat more than you need. (2)
In one study performed at the University of Tennessee in 2004 patients showed that a reduction in insulin improved weight loss. The summary concludes that this study highlights the promise of reduction of insulinemia as a primary goal in successful weight loss therapy (3)
This is why keto diets work so well… they are all diets that center around the reduction of glucose and insulin levels.
So how does this tie into intermittent fasting?
Think about it like this… every time you eat your insulin rises, when your insulin rises your body activates its fat storing hormones. Carbohydrates, particularly sugar, have the most dramatic effect on insulin spikes.
So, by not eating for the 16-20 hour window (this would be the 16-8 method or the 20-4 method of IF) you are mitigating that insulin spike to a much smaller, finite amount of time. Vice versa when you eat 5 to 6 times per day, your insulin levels are consistently elevated.
The reason this pairs so well with a ketogenic diet is because:
- You are already eating a low insulin based diet, meaning even when you eat your body is keeping those fat storing hormones at bay.
- The keto diet makes you fat adapted, meaning that your body is going to turn to fat as it’s primary fuel source and burn off that fat storage much faster and more efficiently
Here is what a perfect day looks like for me…
~6am. I drink my coffee or tea and plenty of water throughout the day, but no calories! Some include artificial sweeteners and “natural flavors” because they are calorie free, but in my opinion your body still needs to process it to some level, so that is less time for the body to perform it's internal cleanup. I suppose coffee, even black coffee would be no different, but I need my coffee and I can do without the sweetened beverages, artificial or not.
~3pm. I will break my fast. I usually try and make this meal particularly fat heavy. I will do coffee with a shot of MCT oil and heavy cream. I prefer it over butter because I think it tastes and mixes better. I will drink that with some avocado and a few nuts.
~5pm. get my workout in.
~7pm eat my face off. Now by this point, I’ve worked out and I’m pretty hungry. This is when I take in the bulk of my veggies and proteins. Sticking to the keto rules I will try to keep my protein moderate, a few big helpings of veggies and whatever fat source I need to round out the macros, whether that be a fat bomb or some coconut oil in my tea. I love tea.
**Once you’re fat adapted 70% fat isn’t necessarily needed. It’s now your primary energy source, but it’s also locked and loaded, ready to be burned up, so you don’t need to force it. Your body understands that this is now the goto energy source. Point being, eat fats to satisfaction and and your body will metabolize the rest from your stored fat.
International Journal of Obesity (2004)- Obesity, leptin resistance, and the effects of insulin reduction