Which is healthier, butter or margarine?

A friend recently asked me which is a healthier choice: whipped butter or a buttery spread. Having a master’s degree in nutrition, I get a lot of nutrition questions, but I hadn’t been asked this one before.

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Without looking at the labels, I really couldn’t give her a good answer, so I hit the supermarket to compare products. I found several shelves stocked with butter and the various spreads you can use in its place. I decided to go all out and basically analyze the whole category. So if you’re wondering how to make sense of so many spreads, here’s help:

Butter: Basically, no matter what brand you pick, butter has the following nutritional profile per tablespoon: 100 calories, 11 grams of fat, 7 grams of saturated fat. (The grades, which range from AA to B, with AA being the best, have to do with quality—flavor, color, texture, etc.) It’s a steep calorie count for sure, but heart-healthy oils, such as olive and canola, pack just as many calories (or more); what makes butter “bad” for your heart is its high level of saturated fat—which, eaten in excess, can boost blood cholesterol levels.