For years, fat was a four-letter word. We were urged to banish it from our diets whenever possible. We switched to low-fat foods. But the shift didn’t make us healthier, probably because we cut back on healthy fats as well as harmful ones.
You may think fat is bad for you, but your body needs some fat from food. It’s a major source of energy. It helps you absorb some vitamins and minerals. Fat is needed to build cell membranes, the vital exterior of each cell, and the sheaths surrounding nerves. It is essential for blood clotting, muscle movement, and inflammation. For long-term health, some fats are better than others. Good fats include monounsaturated and polyunsaturated fats. Bad ones include industrial-made trans fats. Saturated fats fall somewhere in the middle.
All fats have a similar chemical structure: a chain of carbon atoms bonded to hydrogen atoms. What makes one fat different from another is the length and shape of the carbon chain and the number of hydrogen atoms connected to the carbon atoms. Seemingly slight differences in structure translate into crucial differences in form and function.
But not all fats are created equal. Some fats are better for you than others and may even help to promote good health. Knowing the difference can help you determine which fats to avoid and which to eat in moderation.
Research is continuing to evolve on dietary fat, but some facts are clear.
Dietary fat, also known as fatty acids, can be found in foods from both plants and animals. Certain fats have been linked to negative effects on heart health, but others have been found to offer significant health benefits.
Fat is as essential to your diet as protein and carbohydrates are in fueling your body with energy. Certain bodily functions also rely on the presence of fat. For example, some vitamins require fat in order to dissolve into your bloodstream and provide nutrients.However, the excess calories from eating too much fat of any type can lead to weight gain. Foods and oils contain a mixture of fatty acids, the predominant type of fat they contain is what makes them more healthy or less healthy.
What are the less healthy fats?
Two types of fats — saturated fat and trans fat — have been identified as potentially harmful to your health. Most of the foods that contain these types of fats are solid at room temperature, such as:
- beef or pork fat
Trans fat should be avoided while saturated fats should be eaten very sparingly.
Saturated fat: Use sparingly
Most saturated fats are animal fats. They’re found in high-fat meats and dairy products.
Saturated fat sources include:
- fatty cuts of beef, pork, and lamb
- dark chicken meat and poultry skin
- high-fat dairy foods (whole milk, butter, cheese, sour cream, ice cream)
- tropical oils (coconut oil, palm oil, cocoa butter)
Eating too much saturated fat can increase blood cholesterol levels and LDL (bad) cholesterol levels. Traditionally, doctors have linked higher saturated fat intake with increased heart disease risks. This idea has been called into question more recently. According to Harvard University, researchers now think saturated fat may not be as bad as once thought — but it still isn’t the best choice for fats.
A 2015 review of 15 randomized controlled trials looked at saturated fats and heart disease. The researchers concluded that replacing saturated fat in your diet with polyunsaturated fats can reduce your heart disease risk.While the risk reduction is low, these differences could make a difference to your health.
A 2017 journal article published in the British Journal of Sports Medicine reported that the risks of LDL (bad) cholesterol had previously been overstated, particularly when it comes to a negative effect on heart health. The article recommends comparing your total cholesterol level to your HDL (good) cholesterol level instead. Doctors associate a higher ratio with increased insulin resistance and heart problems.
Trans fat: Avoid when possible
Short for “trans fatty acids,” trans fat appears in foods that contain partially hydrogenated vegetable oils. These are the worst fats for you. You might find trans fat in:
- fried foods (French fries, doughnuts, deep-fried fast foods)
- margarine (stick and tub)
- vegetable shortening
- baked goods (cookies, cakes, pastries)
- processed snack foods (crackers, microwave popcorn)
Like saturated fat, trans fat can raise LDL (bad) cholesterol, also known as “bad” cholesterol. Trans fat can also suppress HDL (good) cholesterol levels or “good” cholesterol. Doctors have also linked trans fats to an increased risk of inflammation in the body. This inflammation can cause harmful health effects that may include heart disease, diabetes, and stroke.
Some margarines will contain trans fats if they’re made with hydrogenated ingredients, so make sure to always choose non-hydrogenated versions.
Labeling laws allow food companies to round down to zero and claim “no trans fats” or “zero grams of trans fats” if the amount per serving is less than 0.5 g, despite still containing hydrogenated oils.
It’s important to ignore the front-of-package marketing and always read the ingredient list.
Foods with good fats
Doctors consider monounsaturated fat and polyunsaturated fat more “heart-healthy” fats. These fats are better choices for your diet.
Foods that primarily contain these healthier fats tend to be liquid when they’re at room temperature. An example is vegetable oil.
This type of helpful fat is present in a variety of foods and oils.
Research has consistently shown that eating foods that contain monounsaturated fat can improve your blood cholesterol level and decrease your risk for cardiovascular disease. These foods include:
- nuts (almonds, cashews, peanuts, pecans)
- vegetable oils (olive oil, peanut oil)
- peanut butter and almond butter
Polyunsaturated fats are known as “essential fats” because they cannot be made by the body and we must get them from foods. Plant-based foods and oils are the primary sources of this fat.
Like monounsaturated fat, polyunsaturated fat can decrease your risk for heart disease by lowering blood cholesterol levels, according to the American Heart Association.
A certain type of this fat, called omega-3 fatty acids, is particularly beneficial for your heart.
Omega-3s appear to not only decrease the risk of coronary artery disease but also help lower blood pressure levels and guard against irregular heart rates. The following types of foods contain omega-3 fatty acids:
- chia seeds
- canola oil
In addition to omega-3 fatty acids, you can find polyunsaturated fat in the following foods, which contain omega-6 fatty acids:
- roasted soybeans and soy nut butter
- seeds (sunflower seeds, pumpkin seeds, sesame seeds)
- vegetable oils (corn oil, safflower oil, sesame oil, sunflower oil)
- soft margarine (liquid or tub)
The avocado is different from most other fruits. Whereas most fruits primarily contain carbs, avocados are loaded with fats.
Avocados are about 77% fat, by calories, making them even higher in fat than most animal foods.
The main fatty acid is a monounsaturated fat called oleic acid. This is also the predominant fatty acid in olive oil, associated with various health benefits.
Avocados are among the best sources of potassium in the diet, even containing 40% more potassium than bananas, a typical high potassium food.
They’re also a great source of fiber, and studies have shown that they can lower LDL cholesterol and triglycerides while raising HDL (the “good”) cholesterol.
Even though they are high in fat and calories, one study shows that people who eat avocados tend to weigh less and have less belly fat than those who don’t.
Cheese is incredibly nutritious. This makes sense, given that an entire cup of milk is used to produce a single thick slice of cheese. It is a great source of calcium, vitamin B12, phosphorus and selenium, and contains all sorts of other nutrients. It is also very rich in protein, with a single thick slice of cheese containing 6.7 grams of protein, the same as a glass of milk.
Cheese, like other high-fat dairy products, also contains powerful fatty acids that have been linked to all sorts of benefits, including reduced risk of type 2 diabetes.
Dark chocolate is one of those rare health foods that taste incredible. It is very high in fat, with fat at around 65% of calories. Dark chocolate is 11% fiber and contains over 50% of the RDA for iron, magnesium, copper, and manganese.
It is also loaded with antioxidants, so much that it is one of the highest-scoring foods tested, even outranking blueberries.
Some of the antioxidants in it have potent biological activity and can lower blood pressure and protect LDL cholesterol in the blood from becoming oxidized.
Studies also show that people who eat dark chocolate 5 or more times per week are less than half as likely to die from heart disease, compared to people who don’t eat dark chocolate.
Some studies show that dark chocolate can improve brain function and protect your skin from damage when exposed to the sun.
Just make sure to choose quality dark chocolate, with at least 70% cocoa.
Whole eggs used to be considered unhealthy because the yolks are high in cholesterol and fat. A single egg contains 212 mg of cholesterol, which is 71% of the recommended daily intake. Plus, 62% of the calories in whole eggs are from fat.
However, new studies have shown that cholesterol in eggs doesn’t affect the cholesterol in the blood, at least not in the majority of people. What we’re left with is one of the most nutrient-dense foods on the planet.
Whole eggs are loaded with vitamins and minerals. They contain a little bit of almost every single nutrient we need. They even contain powerful antioxidants that protect the eyes, and lots of choline, a brain nutrient that 90% of people don’t get enough of.
Eggs are also a weight loss friendly food. They are very fulfilling and high in protein, the most important nutrient for weight loss. Despite being high in fat, people who replace a grain-based breakfast with eggs end up eating fewer calories and losing weight.
The best eggs are omega-3 enriched or pastured. Just don’t throw away the yolk, that’s where almost all the nutrients are found.
One of the few animal products that most people agree is healthy, is fatty fish. This includes fish like salmon, trout, mackerel, sardines, and herring.
These fish are loaded with heart-healthy omega-3 fatty acids, high-quality proteins, and all sorts of important nutrients.
Studies show that people who eat fish tend to be much healthier, with a lower risk of heart disease, depression, dementia, and all sorts of common diseases.
If you can’t (or won’t) eat fish, then taking a fish oil supplement can be useful. Cod liver oil is best, it contains all the omega-3s that you need, as well as plenty of vitamin D.
Nuts are incredibly healthy. They are high in healthy fats and fiber and are a good plant-based source of protein.
Nuts are also high in vitamin E and loaded with magnesium, a mineral that most people don’t get enough of.
Studies show that people who eat nuts tend to be healthier and have a lower risk of various diseases. This includes obesity, heart disease, and type 2 diabetes.
Healthy nuts include almonds, walnuts, macadamia nuts, and numerous others.
Chia seeds are generally not perceived as a “fatty” food. However, an ounce (28 grams) of chia seeds contains 9 grams of fat.
Considering that almost all the carbs in chia seeds are fiber, the majority of calories in them come from fat. In fact, by calories, chia seeds are around 80% fat. This makes them an excellent source of high-fat plant food.
These aren’t just any fats either, the majority of the fats in chia seeds consist of the heart-healthy omega-3 fatty acid called ALA.
Chia seeds may also have numerous health benefits, such as lowering blood pressure and having anti-inflammatory effects. They are also incredibly nutritious. In addition to being loaded with fiber and omega-3s, chia seeds are also packed with minerals.
Extra Virgin Olive Oil
Another fatty food that almost everyone agrees is healthy, is extra virgin olive oil. This fat is an essential component of the Mediterranean diet, which has been shown to have numerous health benefits.
Extra virgin olive oil contains vitamins E and K, and is loaded with powerful antioxidants. Some of these antioxidants can fight inflammation and help protect the LDL particles in the blood from becoming oxidized.
It has also been shown to lower blood pressure, improve cholesterol markers, and have all sorts of benefits related to heart disease risk.
Out of all the healthy fats and oils in the diet, extra virgin olive oil is the king.
Coconuts and Coconut Oil
Coconuts and coconut oil are the richest sources of saturated fat on the planet. About 90% of the fatty acids in them are saturated.
Even so, populations that consume large amounts of coconut do not have high levels of heart disease and are in excellent health.
Coconut fats are different from most other fats and consist largely of medium-chain fatty acids. These fatty acids are metabolized differently, going straight to the liver where they may be turned into ketone bodies.
Studies show that medium-chain fats suppress appetite, helping people eat fewer calories, and can boost metabolism by up to 120 calories per day.
Many studies show that these types of fats can have benefits for people with Alzheimer’s, and they have also been shown to help you lose belly fat.
Real, full-fat yogurt is incredibly healthy. It has all the same important nutrients as other high-fat dairy products.
But it’s also loaded with healthy, probiotic bacteria that can have powerful effects on your health.
Studies show that yogurt can lead to major improvements in digestive health, and may even help fight heart disease and obesity.
Just make sure to choose real, full-fat yogurt and read the label.
Unfortunately, many of the yogurts found on store shelves are low in fat but loaded with added sugar instead. It is best to avoid those like the plague.
The ketogenic diet is primarily made up of high-fat foods. Fat typically accounts for upwards of 65% of calories on Keto.
What Are the Best Fats for Keto?
When you’re looking to consume healthy, Keto-friendly fats, there are three main types to consider:
- Saturated fats
- Monounsaturated fats
- Polyunsaturated fats
Healthy Saturated Fats for Keto
Saturated fat gets a bad rap. Early animal studies lead to the widespread belief that saturated fats are harmful, and this gave rise to the low-fat craze in the ’70s and ’80s.
However, the good news is that a more recent, in-depth meta-analysis found no link between dietary saturated fat intake and an increased risk of cardiovascular disease or type 2 diabetes
It seems there may be some benefits to moderate saturated fat consumption:
- Saturated fat may reduce levels of lipoprotein-a (Lp(a)), a substance that strongly correlates with heart disease risk
- It may also raise HDL – levels of heart-healthy ‘good cholesterol’
- MCT oil, a type of saturated fat extracted from coconut oil, has been linked with weight loss, improved neurological health, and may even support healthy blood sugar levels.
Sources of Saturated Fat:
Saturated fats are abundant in animal products, but can also be found in a handful of plant-based foods. Common sources include:
- Red Meat
- Full Fat Dairy
- Coconut Oil
- Coconut Milk
- MCT Oil
- Cocoa Butter
Pro tip: Saturated fats are typically more stable at a high heat when compared to other fats, making them perfect for cooking with!
Healthy Polyunsaturated Fats for Keto
Polyunsaturated fats are important for a whole host of reasons, and can be split into two major classes:
- Omega-3 Fats
- Omega-6 Fats
Both are essential fatty acids, meaning your body cannot produce them and they need to be sourced from your diet.
While both types of fat are needed, it’s important to maintain a healthy balance between the two. Consuming an excess of Omega-6s compared to Omega-3s may promote inflammation and poor health outcomes.
Ideally, we’re aiming for a 1:1 ratio, but in the standard western diet, the ratio is often more than 16:1 Omega-6:Omega-3.
Omega-3 Benefits & Sources:
Omega-3 fatty acids have been linked to several potential health benefits, including:
- Improved cognitive function and decreased rate of cognitive decline.
- Reduced risk of cardiovascular disease mortality.
- Improved outcomes with mental health challenges like depression.
On your Keto diet, there are a few types of Omega-3s. Aim to consume a mix of both regularly:
- DHA & EPA. These are long-chain Omega-3s found in fatty fish like salmon and mackerel, fish oil, and certain algae. They are important for heart health and brain function.
- This short-chain Omega-3s are converted to DHA and EPA in the body, but the conversion process is not always that efficient – just 2–10% of the ALA you consume is converted [*]. Good sources include flax, hemp seeds, chia, and walnuts.
Healthy Omega-6 Polyunsaturated Fats:
It’s best to prioritize Omega-3 sources of Omega-6s, but there are still some healthy foods that contain the latter:
- Extra Virgin Olive Oil
- Sesame Oil
- Pine Nuts
- Sunflower Seeds
Keep in mind:
Polyunsaturated fats tend to spoil faster than other fats due to their chemical structure, so are best stored in cool dark places, and should be refrigerated once opened.
And whereas saturated fats are typically heat-stable, polyunsaturated are more volatile and can lead to free radical production and inflammation if heated. So reserve your poly fats for salad dressings!
Healthy Monounsaturated Fats for Keto
Monounsaturated fats are the superstars of the heart-healthy Mediterranean diet, and come with an array of potential benefits:
- Unsaturated fats may aid with weight loss – more so than a low-fat diet.
- They have also been linked with reduced inflammation.
- They support heart health by lowering cholesterol and blood pressure.
Healthy Monounsaturated Fat Sources:
- Avocado Oil
- Extra Virgin Olive Oil
- Pumpkin Seeds
Healthy Keto Fats: Swap This For That
- Margarine for Coconut Oil
- Vegetable Oil for Extra Virgin Olive Oil
- French Fries for Butternut Fries
- Pizza for Keto Cauliflower Pizza
- Cookies for Keto Cookies
- Boxed Cakes for Vanilla Keto Cake
Because Keto is a diet that relies so heavily on fats, it’s super important to ensure you’re getting the highest quality sources possible.
That means a good balance between animal and plant-based saturated, monounsaturated and polyunsaturated fats, and minimizing or avoiding artificial trans fats where you can.
The key takeaway is to do your best and aim for a wide range of healthy high-fat foods that set you up for long-term success!