So far, we have gone over the two different types of metabolism, fat or carb based. What is the difference between the two of these and why is it important to survival?
The fate of hungry cells
At any time, the body will be in a state of carb or fat metabolism. It takes days to switch into ketosis, and often more than a week for people who have never been in it before. Because of this, carbs are a great source of fuel when they are abundant, but leave you out in the cold once you lose access, as you would in a survival situation.
Let’s say you had two twins, one who was
in a state of carb metabolism and one who was in a state of fat metabolism. Imagine your disaster of choice wipes out infrastructure and in three days, there is no access to survival foods. Both are now in a state of starvation. Let’s also say for the sake of the argument that they are in a state of physical exertion, moving over land, defending themselves and porting supplies with them.They are expending energy, which has to come from somewhere. In this case, the body.
Twin #1 is in a state of fat metabolism. His cells are primed to accept ketones as a fuel source. In a state of starvation with energy to expend, his cells will crave ketones. Thankfully, he will have an abundant source of ketones in his body fat. Fat will be converted into usable calories at 9 calories per gram. For the average person, this is a lot of energy. Taking an average weight of 175 lbs and a healthy bodyfat percentage of 15%, this twin will be able to lose 10% of his weight in fat, or 17.5 lbs before it becomes unhealthy. This leaves close to 8000 grams of usable fat, which translates into a massive 72000 calories before twin#1 starts losing more essential tissue.
Twin #2 is used to using glucose as a fuel source. Without carbohydrates to eat, his cells will have to adapt to ketosis. In the mean time, it will be a rough transition. Some symptoms well known to low carb dieters include brain fog, sleepiness, lack of energy and headaches. During my time with keto diets I also experienced a few nasty migraines as well. This will last for a few days, but could be as long as a week depending on the dietary history. Meanwhile, the world may be falling apart and precious time is being lost.
One of the more sinister consequences is the loss of muscle tissue. As you may recall, proteins are very close to carbohydrates and when needed, can be converted. Because of this, people in a state of carbohydrate metabolism lose more muscle than those in fat metabolism. The protein is scavenged and broken down into the preferred fuel source, carbohydrate. In
a state of physical exertion, this is all the more likely.
The x factor
While calories may be available, there are critical nutrients to be considered for survival. Stay tuned to the next post in the series for the essential nutrients to supplement calories in a starvation state.