The holiday season is quickly approaching, and your thoughts might be turning to the damage that this time of year can do to your waistline, and maybe you’re even making some early resolutions to avoid all that fatty food that you ate last year. But wait! Before you start swearing off anything that isn’t low- or no-fat forever and ever, you need to know that not all fat is bad for you. In fact, fat is one of three key macronutrients (along with protein and carbs) that our bodies need, and it can play an important role in our health and longevity – you just have to know which fats to eat, and how to incorporate them into your diet.
The History of Our Complicated Relationship with Fat
Over the last few decades, fat has definitely gotten a bad rap, but it hasn’t always been that way. There was a time that people were trying to find ways to get more calories into their diets, and fat seemed like the best option because it was the most efficient way to get energy, since it contains more calories by weight than any other nutrient.
But even before doctors began recommending low-fat diets, the idea that restricting your fat intake, and thus eating fewer calories, as a way to keep slim was creeping into mainstream culture as early as the late 19th century. Penny scales were popping up in public so women could weigh themselves, and by the 1920s, it was common for some women to diet so they could feel good wearing the more revealing fashions of the day.
With that being said, though, that was just a small portion of the population, and in the mid-20th century in America, many people were still eating a pretty fatty diet, with a heavy emphasis on meat and other animal products. But it was at this time that researchers began to look at a possible correlation between high-fat diets and heart disease; after all, coronary heart disease was the leading cause of death in the 1940s, and scientists wanted to get to the bottom of things.
Slowly, over the next few decades, researchers began to tout the idea that fatty diets were what was causing our poor health, and the government and media began to catch on; by the 1980s the idea of living a low-fat lifestyle became what Ann F. La Berge calls an “ideology.” According to La Berge writing in the Journal of the History of Medicine and Allied Sciences, “Supported by scientific studies, promoted by the federal government, the food industry, and the popular media, low fat became the dominant dietary belief of health care practitioners, health popularizers, and a substantial part of the American populace.”
But should we be holding onto the idea that fat is always bad for us?
Do We Need Fat?
Anyone out there remember the dieting fads of the 1990s? If you never had a Blockbuster Video card, let us fill you in: eating healthy was all about eating low-fat foods, including simple carbs like bread and pasta, even if those low-fat foods were artificially manufactured to have less fat in them (and were often made to taste better with extra sugar, like “low-fat” cookies, or were stabilized with all sorts of chemicals, like fat-free dairy products). And, while we’ve definitely moved on from a lot of the worst ideas of the time, many of us still have trouble letting go of the idea that the lowest fat diet is always the best.
But remember the fact mentioned above that fat is one of three key macronutrients? Fat doesn’t just taste good, you actually need fat to live: at a minimum, you need 10% of your calories to come from fat for your body to function properly. And fat does some pretty important things for your body, like:
- Provides essential fatty acids
- Keeps your skin and hair soft
- Helps the body absorb fat-soluble vitamins, like vitamins A, D, and E
- Give you a source of energizing fuel
- Supports cell growth
- Protects your organs
So how do you find a balance between the unhealthy aspects of fat and the necessity of having it in your diet? By knowing which are the best fats to eat, and how much of them you should actually have in your diet.
The Good, the Bad, and the In-Between
So let’s take a look at three basic types of fats: trans fats, saturated fats, and unsaturated fats.
Trans fats are the worst of the three, and are the ones you should try to eliminate from your diet altogether – in fact, they are actually banned in a lot of places. These fats are a byproduct of a process called hydrogenation that is used to turn healthy oils into solids and to prevent them from becoming rancid. The consensus on them is that they raise bad (or LDL) cholesterol and reduce good (or HDL) cholesterol. They are also believed to create inflammation, which is linked to heart disease, stroke, diabetes, and other chronic conditions, and to contribute to insulin resistance, which increases the risk of developing type 2 diabetes. And get this: according to studies, for every 2% of calories from trans fat consumed daily, the risk of heart disease rises by 23%.
What type of food contains trans fats? Usually commercially produced “junk” food, sweets, and fried foods. Look for the phrase “partially hydrogenated oil” on the label, or do a little detective work: subtract the amount of saturated fat and the mono and polyunsaturated fats listed on the label, and you’ll be left with the amount of trans fat in the product.
Saturated fats are a bit more complicated. While some people lump all saturated fats in with the bad fats, they’re now usually considered more of an “in-between” type of fat that still needs a little more study, and doesn’t necessarily need to always be avoided – depending on the source of it, of course. Some studies suggest that saturated fats increase bad cholesterol, while some recent analyses of data suggest that there is not enough evidence that saturated fat increases the risk of heart disease. It’s important to note, though, that research has also found that replacing saturated fat with polyunsaturated fat might reduce risk of heart disease, so to be on the safe side, you should limit your saturated fat intake to under 10% of your daily calories.
There are a lot of foods that contain saturated fat, many of which you probably eat fairly regularly, like meat and full-fat dairy products. Saturated fats are solid at room temperature: think cooled bacon grease, or coconut oil – which proves that saturated fats really can run the gamut in terms of their effects on your health! Consider this: an avocado contains the same amount of saturated fat as three slices of bacon, but, while eating bacon can increase your bad cholesterol, eating about a half to 1.5 avocados daily actually reduces levels of bad LDL cholesterol, according to a study of 229 adults. You have to think about the benefits of each type of food, since there are foods that have a balance of both good and bad – and we have to remember that we eat whole foods, not just nutrients in a vacuum!
Unsaturated fats are considered the good guys of the fat world. This type of fat is liquid at room temperature, and is further broken down into 2 categories:
- Monounsaturated fats, which are a big part of the Mediterranean diet, and are thought to be one of the reasons why people who live in that region are so healthy despite eating a higher-fat diet. Some research suggests that monounsaturated fats like olive oil, which are rich in antioxidants, can protect your cells from DNA damage and help lower your risk of heart attack and stroke. One study even found that for every 10g per day increase in olive oil consumption, cardiovascular disease risk dropped by 10%. Just remember that fat is still loaded with calories, so don’t go too crazy!
You can get this healthful type of fat from things like:
- Olive oil
- Peanut oil
- Canola oil
- Polyunsaturated fats are super important for our bodies: in fact, they’re considered essential fats, because they are used to build cell membranes and the covering of nerves, and are needed for blood clotting, muscle movement, and inflammation. These fats are those much-talked about omega-3 and omega-6 fatty acids, and replacing saturated fats with them could help to lower bad cholesterol and triglycerides, as well as raise good cholesterol.
Get these good guys from:
- Fatty fish such as salmon, mackerel, and sardines
- Canola oil
- Unhydrogenated soybean oil
Can You Have Too Much of a Good Thing?
With all of the above being said, we do have to point out that, while some fats are indeed healthy, it’s not really a good idea to go hog-wild on any food that’s loaded with fat. Remember, it’s all about balance and moderation, and getting a good variety of nutrients, so while a bit of guac is ok (well, it’s more than ok in our book!), you shouldn’t be sitting down to a giant tub of it every day.
That’s because fat, whatever type it is, is very calorie-dense, containing 9 calories per gram, which can really add up. So while many nutritionists, dieticians, doctors, and researchers have reversed course on that one-size-fits-all strict low-fat diet, it’s important to remember that the old calories in/calories out rule applies, and you need to balance anything you eat with a healthy lifestyle that includes exercise and eating well. In fact, some studies have shown that heart disease is actually more closely linked to extra calories and weight gain than to saturated fat, so it really is all about your lifestyle as a whole.
So there you have it: the low-down on whether low-fat is really the way to go. Turns out we really do need fat in our diets, no matter what all those commercials for fat-free products say! It’s just a matter of which fats are best, as well as knowing how to incorporate them in our diets in a healthy way. You’ve heard it a million times, but it bears repeating: everything in moderation! Now, enjoy a few holiday cookies, but balance them out with something good for your body – and don’t forget to get out there and take a few brisk walks to enjoy the lights and keep your blood flowing!