The McDonald's salad with the lowest calories may surprise you

Fast food chains get a bad rap for their food being unhealthy, but what you might not expect is that the foods that are highest in calories, fat, and even carbs or added sugars are the foods you might be ordering while believing you are making a good choice. This isn't only true of McDonald's either — it happens at Chick-fil-A and Wendy's, among others. If you're eating a salad at a fast food joint, chances are you don't want it to contain more calories than a Big Mac (via CNBC). 

It's easy to decide to order a salad on the go when you're in a hurry or need to eat en route while balancing a hectic schedule. However, you might regret that healthy-seeming choice once you know more about the nutrition of it. Some of the salads at McDonald's are way worse than you might think. For example, the Premium Southwest Salad with Crispy Chicken packs 430 calories, 20 grams of fat, 38 grams of carbs, and 12 grams of sugar for only 26 grams of protein. That doesn't include dressing or croutons either (via McDonald's). There are, however, a few better salad options at the chain.

This is the salad on the McDonald's menu you should opt for

While getting grilled chicken on any of the salads automatically results in better nutrition facts, ordering a salad without any chicken at all will really lower the calories — along with the protein too. Sometimes the difference in carbs between salads with grilled chicken and those without chicken might not be worth giving up the protein. Though the Premium Southwest Salad goes from the worst salad for you with fried chicken to one of the best when ordered without chicken, there are better salad options on the McDonald's menu yet.

The Premium Caesar Salad is the one you should probably stick to when ordering a salad from McDonald's. If you order it with grilled chicken, the salad will have 220 calories, six grams of fat, 12 grams of carbs, five grams of sugar, and 30 grams of protein. That's not bad at all for a fast-food meal. If you eliminate the chicken altogether, the salad comes down to 90 calories, four grams of fat, nine grams of carbs, four grams of sugar, and seven grams of protein. Whatever salad you order, opt for the low-fat dressings (which are between 40 and 60 calories, but fairly high in sodium) or the Creamy Southwest dressing which is 100 calories, but has far less sodium. There's no sense in ordering the healthiest salad if it's topped with an unhealthy dressing.