Giant caloric content of St. Patrick’s Day McDonald's Shamrock Shake treat may scare you.

It’s that time of year again… McDonald’s Shamrock Shake is back! However, you might want to spend a few extra hours at the gym this week if you plan on indulging in the minty, seasonal shake.

Nicole Danna, a food blogger for Broward New Times, said the calorie count in one shake is equivalent to 1.25 Big Macs, 1.5 orders of fries, 2.5 hot fudge sundaes, or about three Egg McMuffins."

Introduced in 1970 as the St Patrick’s Day Shake, the treat has since become a cult favorite.

According to McDonald’s website, a small version of the Shamrock Shake has 530 calories and 15 grams of fat. The medium size has 660 calories and 19 grams of fat, while the large 22-ounce version has 820 calories and 23 grams of fat."

Mary Hartley, registered dietitian and online nutritionist at AskMaryRD said: “The 82 grams of sugar is the worst. It’s like eating around six slices of bread all at once.

"The saturated fat is also high, at 40 percent of the daily limit (the goal is 10 percent). On the other hand, it is loaded with calcium (460 milligrams).”

If those numbers don’t scare you off, the site will help you track down the McDonald’s locations nearest you serving the seasonal treat.