Many of you probably remember the meaning of pi from your high school math classes. Pi, the ratio of a circle’s circumference to its diameter, is 3.1415926 in decimal form. We round that number down to 3.14 each year to celebrate Pi Day on March 14.

Now, you could celebrate this day by calculating math equations … or you could eat pie. After all, pies are circular. If you’re still working on shedding off weight from holiday pies, you can celebrate today, too, by making your pie healthier.

A key to healthy pies is making your own crust. Instead of purchasing a premade crust loaded with preservatives, use flour, sugar, water and healthy fats to make your own.

You can make nearly any pie healthier by substituting ingredients. When making the crust, replace all-purpose white flour with whole-wheat flour to add fiber and cut calories. If you want to add more nutrition to the crust, use almond flour to add protein and vitamins. And, in some recipes, you can lower the pie’s fat content by swapping butter for Greek yogurt or reduced-fat sour cream.

Like peanut butter? Make a healthy and delicious peanut butter yogurt pie by mixing 32 ounces of vanilla Greek yogurt and three-quarters of a cup reduced-fat creamy peanut butter. Spread the blend into a pie shell of your choice and refrigerate overnight. A slice of this pie has nearly 14 grams of protein.

Prefer apple pie? Use a whole-wheat pie crust and cut out the added sugar to keep the flavor without the guilt.

Almost any pie you want can pack a flavorful punch without hurting your waistline. For recipes and ideas, you can google the name of your favorite pie and the word healthy. By taking the time to make your own pie and substituting ingredients, you can enjoy this Pi Day in a guilt-free way.