You get out of your body what you put into it. Eating right takes discipline, but the way you’ll feel mentally and physically is more than worth it so try to treat your body more like a temple and less like tent. There are five simple tenets to Spartan eating:

1. Avoid processed foods.

Processed foods don’t resemble a living plant or animal and have gone through significant processes in a factory. Soda, candy, cookies, chips, hot dogs, sugary cereals—this is crap, plain and simple. These foods have less nutritional value and put a lot of unwanted chemicals in your body.

2. Eat nothing sometimes.

It’s not the end of the world to miss a meal. Plus, some evidence suggests that an occasional fast—something like 16- to 24-hours—is good for you. It’s probably no accident that so many cultural traditions around the world include some type of fasting.

3. Eat whole foods.

Whole foods are fantastic, especially vegetables and some fruits. Whole foods are nutrient-rich edibles that haven’t undergone industrial processing like organic fruits, vegetables, meats and grains.

4. Eat only when you’re hungry.

Your body knows when to eat. Don’t force feed it.

5. Adapt.

No diet works perfectly for everyone and, unless you have a serious allergy, no single food is going to kill you. We humans can generally eat any natural food. Be flexible.