Nothing quite does go better with steak than a baked potato, does it? You may or may not know this, but white potatoes are extremely high on the glycemic index, which means they digest quickly and can send insulin levels skyrocketing. That may spell post-workout glory, but when you’re having a late-night steak dinner with pals — it’ll be doing much more harm than good.

When it comes to yams or sweet potatoes, they’re loaded with vitamins and are healthier than they get credit for – especially when being used in pies and topped with marshmallows.

Which is Better for Building Muscle?

They are both good for you and in many cases would be perceived as equally nutritious, BUTit is not that simple.

Why are They Equal?

We tapped into archives that showcased some top-notch research from Jordana Brown of FLEX Magazine. While FLEX is a very hardcore publication for competitive bodybuilders, their nutritional research is one of the best sources out there because they examine a collection of studies and scientifically breakdown the compounds of what you’re eating.

In short, they are both good for you as long as you are eating them at the right time. Sweet potatoes make for a better staple of your everyday diet, while white potatoes should be eaten with more discretion given their abundance of potassium and folate.

Jordana Brown suggests the following:

There actually is a spot in your diet for each, depending on when you eat them. Overall, they’re pretty evenly matched: both contain strikingly similar amounts of calories, protein, carbs and fat. In the content of a couple of key minerals, though, white potatoes are the winner. They contain more than three times the folate of sweet potatoes and have more potassium (which is important for postworkout recovery) than their sweet cousins. So feel free to eat white potatoes, just make sure it’s right after working out, when the insulin boost will be directed straight to your muscles.

Sweet potatoes, on the other hand, can (and should) be eaten at any meal. Their claim to fame (as one of the healthiest foods on the planet) is their beta-carotene content. Besides being a potent antioxidant, beta carotene is responsible for aiding growth and repair of the body’s tissues, which include muscle. That staggeringly high carotenoid content accounts for the sweet potato’s color and possibly its slower rate of digestion, which stabilizes blood sugar and reduces insulin resistance.