Food is Fuel

...and you're body is a power plant. Think of it a lot like a steam engine when you fuel the fire in a steam engine there is more heat to create more steam and thus more power from the engine. The engine doesn't work unless there is fuel to burn. (for those of you who need a refresher on steam engines check out How Stuff Works)

The difference is that our bodies also have batteries. The problem being that the batteries for our body tend to come in the form of love-handles rather than the nice copper tops. That's right, fat is the human battery. It's the primary way that we store energy for using later and it's pretty stinking good at storing a lot of energy (we can talk more later about how fat really isn't a bad thing unless you have too much of it).

Food is fuel. Sounds great, but what does it really mean. It means that what you eat lets your body do what it needs to do. There are three main nutrients that give energy to your body, protein, fat and carbohydrate. There is potential energy stored up in all of the chemical bonds that exist in the foods you eat. When you eat, your body breaks those bonds and transfers the energy in them to make other molecules your body can use, primarily ATP. Don't worry that's about the end of the sciencey discussion for now. The bottom line being that if you don't eat, you don't get the energy you need to do the things you like to do like running, biking, swimming etc.

There are three main plans that your body has for the fuel you put into it: 1) turn it into glucose right away to maintain your blood sugar levels and feed your brain, 2) store some energy in small energy stores for muscles called glycogen so that your muscles have the immediate energy they need to do things like walk, jump, sit, stand, etc. and 3) store whatever is left as fat.

Your body's goal is always to use the fuel you give it, even if you give it too much. Now the trick is finding out how much fuel you need and to give yourself the right amount. A good place to start is by doing a simple calculation of a basal metabolic rate. There are lots of calculators on the internet that you can find which will help you do this. The basal metabolic rate really is just a starting point though, because this is the absolute minimum number of calories you need in a day. Which means that even someone who has a sedentary job will burn more calories than their BMR...albeit not a lot more. The more active you are the more calories you burn because your muscles are using more fuel. Makes enough sense, right? If you drove your car 100 miles a day it would need more gas than if you drove it 10 miles a day. It's the same idea. Some calculators will try to compensate for this by giving you an opportunity to estimate activity level, like this one I found or the Livestrong.com calorie calculator. These are only estimates, but they work fairly well.

Not all fuels are created equally, either because you are never getting just one nutrient from what you eat. This is a good thing too. Interestingly enough it is often found that natural whole foods frequently have a combination of nutrients and vitamins that complement each other in such a way to benefit your body. For instance, eating an orange or a bell pepper is a more efficient way for your body to obtain vitamin C than taking supplements...but now we're getting into vitamins and other add ons. They aren't really fuel, but they help your body do what it needs to do with the fuel. We'll leave that for later.

Ultimately you need to choose your fuel carefully. Most people would be quick to agree that eating all fat is no good, but eating all protein is also no good. Foods need to be balanced between nutrients (fat, protein and carbohydrate) and they need to be enough to meet your needs. A caloric deficit--which is what you usually aim for whenever you go on a diet--will make your body lose weight, but it will also stress your body. Remembering that food is fuel will help you realize that when you eat you should be considering the amount of energy you have used or will need to use. The key being balance and establishing a beneficial average quantity.

Until next time, fuel up!