The difference between the runner you are now and the runner you want to be could lie in those unwanted pounds clinging stubbornly to your waistline. Lose weight and you’ll become a lighter, more efficient, and, ultimately, a faster runner. Just how much faster depends on several factors, but 2 seconds per pound per mile is a common figure you’ll see in running books and online.

To unlock all those “free” seconds tied up in your body fat, you could increase your running volume (the hard way), or you could make the following 5 changes to how you approach your daily diet (the easy way).

1. Eat to Run. Don’t Run to Eat.

How often have you treated yourself to some kind of food you normally wouldn’t eat simply because you ran earlier that day? Maybe you’re even the type of runner who has your dietary indulgences planned out before you ever lace up your running shoes. The good news is you’re far from alone. Unfortunately, that’s the only good news.

When you run to eat, you tend to give yourself permission to consume far more calories than you really need (or burned while running) and often turn to junk or comfort foods you would shun on a non-running day. While delicious, these kinds of foods are minefields of saturated fat, processed carbs, and added sugar calories.

By changing your perspective to one where you view food as fuel and start eating to run, you will find yourself looking more closely at the nutritional value of your food. The subsequent increase in nutritional quality and likely decrease in total calories can result in weight loss, increased energy, and better training—all of which add up to you being a faster runner.

Now before you write me off as a nutritional prude and stop reading this article, let me state for the record that I am not advocating you forsake all dietary guilty pleasures. Very few of us have that kind of will power. I, for example, am a huge sucker for oatmeal raisin cookies and have no plans to give them up. However, when I do indulge my sweet tooth, I view it as just that—a indulgence or special treat that must be factored in with my regular daily nutrition, not something I deserve simply because I went running earlier in the day.

2. When Calculating Calories, Use Net Instead of Gross

There are millions of runners out there who are trying to lose weight. Whether that means dropping a few pants sizes or simply shedding those last couple stubborn off-season pounds, the goal is the same: burn more calories per day than you consume. So why doesn’t it always work? The answer could come down to net vs. gross calories.

If you wear a running watch, run on a treadmill, or use an online calculator like this one, it’s easy to find the approximate number of calories your running burns. This number is your gross calories, or the total number of calories you burned while running. What it fails to take into consideration is the fact that you would have burned some calories—hopefully, not as many—if you were simply sitting in a chair for the same amount of time you were running. The minimum amount of calories your body needs to perform its basic functions is known as your basal metabolic rate (BMR) and can be calculated online with just a few pieces of info: age, height, weight, gender. If you subtract this BMR value for the amount of time you spent running from the total number on your watch, you get the net calories you burned. Confused? Let’s look at an example.

Let’s say you ran moderately hard for an hour. Your watch shows you burned 600 calories. Using an online calculator, you determine that your BMR is 1800 calories/day. That translates to 75 calories/hour. If you subtract 75 from 600, you get 525 net calories and a more accurate representation of the “extra” calories you burned by running.

As you can see, and probably inferred from the name, net calories will always be lower than gross calories. This is important when you are trying to lose weight. If you subtract gross calories from your total dietary calories, you will get the impression that you are burning more and creating a larger daily deficit than you really are. This will result in slower weight loss or weight plateaus that can be avoided by simply using net calories instead.

3. Upgrade Your Carbs

You know you need carbs to fuel your muscles. But how do you know which carbs to fuel up with? The answer is simple: Go complex.

The carbs that make their way into your daily diet come in two important forms: simple and complex. Simple carbs are converted into energy quickly. They include refined grains, pastas, and breads; added sugars; and natural sugars, like honey or lactose. Complex carbohydrates are converted into energy much more slowly and come from lightly processed or whole-food sources, like whole grains, fruits, vegetables, and beans.

If your current diet includes mostly simple carbs, especially if those carbs come from highly caloric processed foods with saturated fat and added sugar, you are likely inhibiting both your weight loss and running potential. By upgrading these processed simple carbs to whole-food complex alternatives, you will consume fewer total calories, enjoy more even energy throughout the day, and reduce your daily saturated fat intake.

4. Eat the Right Carbs at the Right Time

Now, I don’t want you to get the idea that all simple carbs are bad or shouldn’t be part of your diet. In fact, there are times when they are your best choice. Before, during, and immediately after a long or intense run, simple carbs—the less processed the better—are ideal for stockpiling and replenishing glycogen, your muscles’ favorite fuel source. Just take a look at the gels, sports drinks, and energy bars we all eat during training and racing. These are all full of simple carbs that can be broken down and quickly delivered to working muscles.

When you aren’t actively preparing for or recovering from a run—the majority of the time—you’ll want to build your diet around complex carbs. Some simple carbs are fine throughout the day and will come with or in the complex carb foods you eat. Just avoid the urge to eat like you’re running when you aren’t. Your muscles and your waistline will thank you.

5. Make Meals at Home

Counting and managing your daily calorie intake is critical when you’re trying to lose weight. And nothing can wreck those daily calories faster than a hungry stomach at a fast food restaurant. It is certainly possible to find low-calorie meal options on the go, but it’s not always easy or convenient.

It’s much easier to control your calories and stick to your weight loss plan if you make your own meals at home. You have complete control over portion size, nutritional quality, and total calories. And while it does take some extra work on the front end, homemade meals can be just as convenient to eat when you’re at the office or driving there from the gym.

One of my favorite options for a workday lunch or easy dinner is a meal of rice, corn, beans, and salsa—all pre-packaged in a microwave-safe bowl. It takes just a few minutes to assemble in the morning and heats up in less time than those frozen diet meals that lurk in the office freezer. It’s a delicious way to get the complex carbs and amino acids my body needs to run its best. Plus, it’s a whole lot cheaper than buying lunch out every day, and that means I can buy my next pair of running shoes that much sooner.

Serious about running nutrition? Check out our “Run Lean, Run Strong” program. Your definitive guide to running nutrition, strength training and injury prevention/treatment.