A Guide to Understanding Fats: Myths and Reality

Each month FBC member and certified nutritionist, Sondi Bruner, helps us navigate the ins and outs of eating a healthy but delicious diet, whether it's adapting to an allergen-friendly diet or figuring out natural sweeteners (and everything in between). This month she tackles a subject that's rife with confusion and myth: the role of fats in our diets.

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Let's face it: nutrition advice can be confusing. One moment an ingredient is the it-food you need to eat all the time, and the next it may kill you. When you add in the multitude of dietary approaches and the various ways to address conditions with food, it can be tough to figure out what to eat!

One area of nutrition that's rife with misinformation is fat. I'm sure many of us remember the low-fat craze, where we ate low-calorie cookies (Snackwells anyone?) and low-fat yogurt and egg whites and were absolutely terrified of fat grams. We've spent more than half a century fearing fat and believing it worsens our health, when in fact it does the opposite — and recent research indicates that most of what we thought was true about fats is wrong. Whoops.

The good news is fat is good for us! And when armed with information, we can begin to make nutritious fat choices that can support our health and wellbeing. Today I'll be debunking some common myths about fats, but first let's talk about what fats are and what they do.

Fatty Functions

Fat plays many essential roles in our bodies. They:

Are a dense source of nourishment (9 calories per gram, compared to 4 calories for both protein and carbohydrates)
Provide us with insulation
Line every cell in the body, providing a barrier that keeps our cell membranes strong
Reduce inflammation
Support the nervous system and brain health
Are a part of bile, which helps with digestion
Balance blood sugar and regulate insulin
Help us make sex hormones
Help us absorb Vitamins A, D, E and K
Nourish skin, hair and nails
Taste really good!

As you can see, these are a lot of important functions. And when you eliminate fats from the diet, you can probably imagine the chaos that might ensue.

Types of Fats

Fats are classified by their size and chemical structure. They come in different sizes (small-chain, medium-chain and long-chain) and have different types of bonds that make up the fat molecules.

Fatty acids are made of the elements carbon and hydrogen, with oxygen at the end of the molecule. When all of the carbon atoms are attached to a hydrogen atom with a single bond, that fat is saturated. When there are one or more double bonds, the fat is unsaturated. Saturated fats look straight, while the chemical structure of unsaturated fats is kinky.

Toasted Coconut Almond Butter --> Get the recipe

Saturated Fats

Saturated fats are very strong and stable. They're solid when chilled or at room temperature, then liquefy when heated. Since they're so strong, they're great for high-heat cooking. Saturated fats include:

Butter
Lard
Tallow
Ghee
Cheese
Coconut oil

Monounsatured Fats (MUFAS)

Understanding Fats: The Myths and Realities | Food Bloggers of Canada — Simple Avocado Toast --> Get the recipe

Monounsatured fats have a single double bond in the fat chain. They're well-suited to medium-heat cooking and are liquid at room temperature. Some foods that contain MUFAs are:

Olive oil
Sesame oil
Nuts and seeds
Avocado
Sunflower oil
Safflower oil
Canola oil
Avocado oil

Polyunsaturated Fats (PUFAs)

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Polyunsaturated fats have multiple double bonds that make them delicate and more susceptible to heat, light and air. They're liquid at room temperature and when chilled. Many PUFAs should not be heated, as they will create free radicals that can damage the body. Other PUFAs will lose nutrient value the longer they're cooked. Some foods that contain PUFAs are:

Egg yolks
Flaxseeds
Pumpkin seeds
Chia seeds
Fish oil
Fish
Walnuts and walnut oil
Sunflower seeds
Hemp seeds

Two types of polyunsatured fats you may have heard of are omega 3 and omega 6. These fats, omega 3s in particular, are very anti-inflammatory and support brain health, balance blood sugar levels, aid with healthy skin, hair and nails and benefit our hearts. If you'd like to learn more, you can read my column about What To Do With Hemp and Chia.

Trans Fats

When liquid unsaturated oils are converted to a solid form, they undergo a process called hydrogenation. Processors stuff hydrogen into these oils to make them solid and shelf-stable so they can be used in a variety of foods without going rancid. Unfortunately, this chemical process creates trans-fatty acids, or trans fats, which are an unnatural type of fat our bodies can't recognize or use.

Trans fats are linked to a variety of negative health issues, including high cholesterol, cardiovascular disease, obesity, allergies, asthma, diabetes and pre-eclampsia. They've been banned by the U.S. FDA in processed foods, but are still permitted here in Canada.

For more information about the best fats and how to use them, check out this Guide to Choosing Healthy Cooking Oils.

Now that we've got the scoop on fats, let's dive into the common misconceptions about them.

Myth: Fats Are Bad for Us

Too many of us have been inculcated with the notion that fats are bad for us and lead to obesity, heart disease and death. As I mentioned at the top of this post, we're learning that much of the advice we were given about fat wasn't supported by scientific evidence.

In 1977, the United States released new dietary advice that recommended reducing dietary fat intake. These guidelines were then adopted by the United Kingdom in 1983. This meta-analysis looked at registered clinical trials that were published before 1983 to determine whether this low-fat advice was warranted. Researchers found that the clinical trials at the time did not show a link between dietary fat and high cholesterol, cardiovascular disease, or mortality, and the U.S. introduced the low-fat guidelines without any actual evidence or testing that they would help.

In this study of nearly 30,000 people that examined fat intake and early mortality, "those who consumed more than 30% of their total daily energy from fat and more than 10% from saturated fat, did not have increased mortality."

So how did the low-fat diet medical advice become entrenched in our culture? For an in-depth look at the politics of science, you might be interested in reading Big Fat Surprise by Nina Teicholz.

Myth: Well, Then Animal Fats Are Bad for Us

Many people understand that plant-based fats like avocados, olive oil, nuts and seeds are nutritious. However, they may assume that animal-based saturated fats are the worst — this is actually incorrect. Consider:

This study concluded that saturated fats do not increase cardiovascular disease (CVD) risk. You know what did? Carbohydrates. Replacing fats with carbs, researchers found, led to inflammation, insulin resistance and a higher CVD risk.
This meta-analysis found that saturated fats didn't increase mortality, cardiovascular disease risk, stroke risk or the risk of developing Type 2 diabetes.
This review suggests that saturated fat isn't the issue, but rather when saturated fats are replaced with sugar this leads to higher cholesterol and risk of CVD.
Ghee, or clarified butter, can reduce the risk of heart disease, support digestion, and prevent weight gain.
Gelatin and collagen, found in animal foods such as bone broth, can support bones and joints, reduce osteoarthritic pain, reduce the signs of aging, and aid with digestion.
Fish, particularly salmon, sardines, anchovies, trout and herring, are low in saturated fat and extremely high in omega 3 fats. Omega 3s are anti-inflammatory and reduce the risk of cardiovascular disease and nourish the nervous system.
Eggs contain a wide spectrum of nutrients, including B-vitamins, protein, omega 3s, the carotenoids lutein and zeaxanthin (important for retinal health), and Vitamin D. They're also a good source of lecithin and the B vitamin choline, which are beneficial to brain health. Research shows that eggs do not raise cholesterol levels or increase the risk of heart disease or stroke.

As I mentioned in my Guide to Animal Products, quality is important. The way an animal is fed and treated affects its nutrient content, so I encourage you to purchase animal products from farmers you trust.

Myth: Fat Makes You Gain Weight

Fat doesn't make you gain weight. It's nutrient-dense, which means you'll stay full for longer after you eat it. Consider:

Coconut oil is used immediately for energy rather than being stored as fat. Studies show that coconut oil reduces waist size in men and abdominal obesity in women.
The ketogenic diet (very low carb, high fat) is effective for weight loss.
In this study that compared low-fat to low-carb diets, both groups lost weight successfully, but the low-carb group experienced a greater reduction in cholesterol and blood pressure than the low-fat group.
Conjugated linoleic acid, a fat found in animal products, boosts our metabolism and helps us burn fat.

Another thing to keep in mind is when companies remove fat from a product, they typically replace it with sugar, artificial sweeteners and chemicals. Emerging research indicates that these diet products could be contributing to weight gain, plus we already know that sugar is linked to metabolic diseases such as diabetes and obesity.

Myth: Fat Causes Cardiovascular Disease

As I mentioned in the above paragraph about animal fats, fat doesn't increase our risk of cardiovascular disease and can actually help to prevent it.

In this interesting study of cardiovascular disease and Mediterranean diets, researchers divided participants into three groups. One group followed a Mediterranean diet with extra olive oil, one group followed a Mediterranean diet with extra walnuts and almonds, while a third group followed a separate low-fat diet. After five years, the two Mediterranean diet groups had a much lower risk of cardiovascular disease and stroke, as well as suffered fewer cardiac events, than the low-fat group. In fact, the study period was actually stopped early because the benefits of the Mediterranean diet were so obvious.

Countless other studies and meta-analyses have concluded that dietary fat isn't associated with cardiovascular disease risk, stroke risk or high cholesterol.

Myth: Plant Fats Are Loaded with Cholesterol

Plant fats like nuts, seeds, oils and avocado do not contain cholesterol — that is something that's only found in animals. Plants do, however, have their own version of "cholesterol" called plant sterols, which actually help us lower our cholesterol levels.

More Fat Facts

Fats Are Anti-Inflammatory

Fats, especially the omega 3s, inhibit inflammation and can be helpful in a number of inflammatory health conditions including rheumatoid arthritis, inflammatory bowel disease, asthma and cardiovascular disease. They've also been shown to be as effective as NSAIDs.

Fats Are Good for the Brain

Our brains are about 60 percent fat, so it stands to reason that eating fat can help our noggins. Fats can improve our memory and cognition, reduce the risk of dementia, lift our mood, and even help our brains work "less hard." DHA, a specific omega 3, has been shown to support brain and eye development, especially in babies and children.

Fats Are Great for Skin, Hair and Nails

Fats, particularly omega 3s, can boost hair growth, improve your skin's moisture and even reduce skin aging.

Fats Can Help Us Balance Blood Sugar

Research indicates that fats, from fish to avocados to nuts and seeds, can benefit blood glucose levels. Also, since many fat sources tend to be rich in protein (fish, nuts, seeds, eggs, etc.), this further helps to keep blood sugar levels even.

How Much Fat Should I Eat?

The amount of fat you eat will depend on your unique health status, activity levels and needs. Standard recommended daily allowances don't take this into account. What I want to emphasize here is fat is not something to be feared and plays an important role in a nutritious diet. Whether you eat plant-based fats only, or a mix of plant and animal fats, I hope you're able to remove the entrenched guilt and simply enjoy and appreciate fats for all they can do for us.