Welcome to Brainstuff, a production of iHeartRadio. Hey Brainstuff, Lauren Vogelbam here. I'm going to start this one off by saying that nutrition is complicated. Our bodies are gloriously weird, and there's still a lot we don't know about how they work, including exactly how the food that we eat affects us. Despite actual millennia of trying to use food to fix pretty much every ailment you can think of around the world, the earliest cookbooks were mostly medical advice.
Over the years, all kinds of health based diet trends have emerged. Apple cider vinegar as a weight loss agent may have first been promoted by the poet Lord Byron back in the eighteen twenties. Is Sylvester Graham, who technically invented Graham crackers in the eighteen thirties, thought that unseasoned, cold whole wheat and hard beds would keep you healthy. He would not enjoy what we've done with Graham crackers today. And there was a fellow back in the seventeen twenties
who simply recommended avoiding swamps to keep yourself slim. A little more recently, there was a major push against fats and cholesterol in our foods. Of people and perhaps particularly marketers, began to wonder whether we could make processed foods healthier, or at least make more people buy them if we
could just take the fat out. If you're older then say ten, and perhaps especially if you lived through the eighties and nineties, you probably remember when every product in the grocery store was touting itself as low fat or low cholesterol. By the way, this was the result of a massive campaign vilifying fat in our diets launched by the sugar industry in the nineteen forties. They had doctors
and researchers on their payroll. We only started to publicly untangle all of this in the past decade or so. Like Twizzlers still sometimes has the words a low fat snack on their packaging, but they didn't really contain any fat to begin with. So all right, if you're looking at something like potato chips, cheese, cookies, or yogurt, how did these products lose their fat content? First off, let's
talk about what fat is. We all know what it tastes like or perhaps looks like in our food, but when you zoom in on the chemical structure, you'll find that all fats have in common long chains of carbon atoms, with some oxygen and hydrogen atoms thrown in to keep things interesting. Those long carbon chains and fat molecules make it really hard for fats to dissolve in water, so generally to get them to dissolve, you need some sort
of organic solvent like chloroform or methylene chloride. You may at first think that washing our fatty foods with one of these solvents would do the trick of removing the fat. It's a good thought, after all, that's often how they remove the caffeine from coffee and tea, but fat actually does a lot for our foods, and simply extracting or dissolving way the fat will leave us with foods that
don't really resemble their original versions. A fat doesn't just add flavor in calories, but also creates texture, helps cooked foods brown, and even extends shelf life. So before we just get rid of the fat, we need to think about how to keep all that flavor and texture in foods so that they're still tasty. Lots of foods, like many fruits, vegetables, and grains, contain only tiny amounts of fat to start with. But let's look at dairy products.
When we first obtain milk from a cow or goat, et cetera, it has a good bit of fat in it. So how do we take whole milk and create skim milk? Oh, the process is pretty simple. Manufacturers put the whole milk into a centrifuge that separates out the fat portion for cream or butter and leaves behind skim milk. The skim milk can then be used to make other dairy products like yogurt or ice cream that are either low fat
or no fat. However, many of these non fat dairy products that are made from skim milk run into the problems we mentioned before. They don't taste as good, their textures are strange, and they may not last as long in our refrigerators. Manufacturers therefore turn to science in order to get flavor, texture, and longevity back in the form of additives. Many low fat or no fat products are created in this way, not by taking the fat out, but by never putting the fat in to begin with.
In the past, food manufacturers experimented with fat replacements like a lestra, but they have yet to find much success in their use. The side effects of these materials resulted in very poor sales. Let's just leave it at the
phrase anal leakage. Okay, so a leustra aside. Instead of making a food product, let's say a cookie and sucking the fat out, which would leave something behind that is no longer anything like a cookie, food scientists need to create that cookie from the start, using non fat based additives to compensate for all that fat brings to the cookie. Let's start with flavor. Fatty cookie ingredients like butter and eggs add a lot of flavor to make up for
the lack of flavor. When those items aren't used, manufactures add in spices, flavorings, and sugar to trick us into not noticing the missing fat. This is why low and non fat foods aren't always less caloric as their diet name might imply. They often have a ton of extra sugar added. A sugar can also help with the texture in baked goods a butt. Manufacturers often add food binders or thickeners to help make up for the missing fat.
Things like pectin, guargum, locus bingum, potato starch, and tappyocha starch will glom onto water molecules and swell up, replicating the full creamy feel of fat and helping retain moisture. In some cases, they and the extra water they require to work, may need extra science help from an added emulsifier or preservative to keep everything together and, in the case of those cookies, make them more shelf stable. A note that all of these additives are generally recognized as safe.
It's honestly the extra and perhaps unexpected sugar you should be concerned with. As researchers have started to untangle that sugar versus fat issue, they found that excess sugar, not fat, is more strongly linked with heart disease. So long story short, getting the fat out of fat free foods, for the most part, actually means never putting it in to begin with. What goes in the place of fat varies, but you'll
often end up with a highly processed food product. And look, these days, whole and natural can be marketing terms as much as fat free. The only text you should be really concerned with on a food package is its nutrition label. That'll tell you how much fat and sugar and other stuff the product contains, and that in turn will let you avoid what you really want to avoid or to have a treat. As we've said before, treats are nice. Today's episode is based on the article how do they
get the fat out of fat free Foods? On how stuffworks dot com written by Mesas Salida brain Stuff It is production of iHeartRadio in partnership with how stuffworks dot Com, and it's produced by Tyler Klang. Four more podcasts my heart Radio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.