Welcome to Mayo Clinic's podcast. This month's topic is "Margarine — Is it healthier than butter?" I'm your host, Rich Dietman.

In today's podcast we're talking about the relative health benefits of margarine vs. butter with Katherine Zeratsky, a registered dietitian at Mayo Clinic, and specialty editor for the Food & Nutrition Center on MayoClinic.com. Katherine, thanks for being with us today.

Katherine Zeratsky: Thank you for having me.

Rich Dietman: Let's get right to it, Katherine. What's better for your heart — butter or margarine?

Katherine Zeratsky: Quite generally speaking, margarine is a better choice. However, if you've been to your local grocery store and checked out the butter-margarine aisle, you'll see that my answer of margarine does not necessarily mean picking out a margarine is an easy thing to do.

Rich Dietman: And that's because there are just so many choices.

Katherine Zeratsky: That is true; there are many choices from different types of butter, straight margarine, to different kinds of margarine-like spreads.

Rich Dietman: Why is this such a difficult choice, and why is it such a tricky proposition to be choosing, first of all, between butter and margarine, and then as you say, trying to pick the best margarine, since that’s probably the better product for us.

Katherine Zeratsky: Butter, quite simply, is a natural product. It’s made from the cream in milk. It’s an animal product. Therefore it contains saturated fat and cholesterol, whereas margarine is made from an oil — oil that’s been hydrogenated. When you hydrogenate oil, it makes it more solid at room temperature. During this hydrogenation process, trans-fatty acids are formed. Trans-fatty acids have been known to act like saturated fat in our bodies, and that’s where the debate lies. Now with the many choices of different margarines, they have made the margarines contain less trans fat, and therefore there are some better choices out there.

Rich Dietman: OK. When choosing a margarine, Katherine, what are some of the general guidelines that you suggest people follow?

Katherine Zeratsky: Look for margarines that contain zero trans fats. These margarines will have at least half a gram or less of trans fat per serving in that product. Next, if at all possible, substitute oils, such as canola oil, olive oil, in place of butter or margarine. Oils are unsaturated fats and are considered a better choice for heart health. Choose tub or soft margarines over stick or hard margarines. The tub or soft margarines are less hydrogenated; therefore they contain less trans-fatty acids. Choose light margarines. Light margarines contain more water and therefore have fewer calories and less fat, overall. If you have high cholesterol, consider using a margarine-like spread, such as Benecol, that has a plant sterol. Plant sterols will help rid your body of cholesterol.

Rich Dietman: OK. What if I don't like the taste of margarine and I really am hankering for that taste that only butter seems to have for me. Are there some blends of butter that you suggest?

Katherine Zeratsky: Yes, just like there are now many choices of margarine, there are choices when choosing a butter. There are butters available that are made with a canola oil. Adding the canola oil to the butter product allows the manufacturer to decrease the overall saturated fat content without adding any trans fat. Another option in choosing butters is a light butter — just like light margarines, water has been incorporated into the mixture, and the water displaces some of the fat in the overall calories. Another option would be whipped butter. Whipped butter simply has air whipped into it, and it's a fluffier, lighter texture. Per serving, this allows for less fat and less calories.

Rich Dietman: So there are some options if a person just can't absolutely live without butter?

Katherine Zeratsky: There certainly are.

Rich Dietman: What about cooking? It's generally suggested that, at least most recipes that call for butter, call for butter and not for margarine. What's a person to do when it comes to cooking with margarine vs. butter?

Katherine Zeratsky: Generally, margarine and butter can be substituted one for one for each other. It's cooking or baking with the light margarines that may produce an altered product. For instance, if you're sauteing with the light butter, the light butter or the light margarine, containing more water, that water will evaporate and not brown your food as you may have wished it to have done. When in baking with a light margarine or a light butter, again the water content and less fat content may not give you the taste or the texture that you had with the original product.

Rich Dietman: What are the dietary recommendations for fat, such as butter or margarine?

Katherine Zeratsky: When choosing a butter or margarine, as we said earlier, it is best to choose ones that are lower in fat, saturated fat and trans fat. However, as a general rule, use butter and margarine sparingly. Fat is a rich source of calories and when we are looking to benefit our own heart health, we need to watch our overall calorie intake as well as our overall fat intake.

Rich Dietman: Thanks very much, Katherine. We've been talking with Katherine Zeratsky, a registered dietitian at Mayo Clinic and specialty editor for the Food & Nutrition Center on MayoClinic.com. You've been listening to a Mayo Clinic podcast. I'm Rich Dietman.