The Science Behind Good & Bad Fats

Good fat

In the health and fitness world, fats often seem to be demonized or misunderstood, yet they form an essential part of your daily diet – or at least, they should! This article gives you the truth about fats, looking at the science behind good and bad fats as well as exactly how they affect your body. You’ll also find details of exactly how much to consume per day for optimal health and performance.

What are fats and where do we get them?

Fats are one of our three macronutrients (the others being carbohydrates and protein). The scientific name for them is triglycerides. Each gram of fat contains 9kcal of energy.

Fats can be obtained from a variety of sources, including animal products, certain vegetables, and nuts.

Different types of fat

There are three major types of fat; saturated, monounsaturated, and polyunsaturated. These terms refer to the number of hydrogen atoms attached to the main molecule; saturated fat has more hydrogen atoms, unsaturated has fewer. This means that saturated fats are more likely to be solid at room temperature.

As a general rule, animal fats tend to be more saturated, as do tropical fats such as coconut oil and palm oil. Vegetable oils tend to be more mono- and polyunsaturated.

What are fats used for?

As you probably already know, humans have a tendency to store fat within our bodies. This is because fat is a great source of energy. Our bodies always want to have some energy reserves in case of starvation.

Fat is also used to protect vital organs, essentially through cushioning, as well as to insulate the body from extremely cold temperatures.

We also need to eat fats in order to obtain essential fatty acids, which cannot be made within our bodies but which are necessary for a huge array of functions, such as supporting our immune system, forming cell membranes, and maintaining various hormonal functions.

How much fat per day?

Since you’re probably reading this article with training in mind, the amount of fat you need to eat per day will largely be determined by the number of calories left over after the other macronutrients have been taken care of.

Let’s look at an example.

Brendan weighs 180lb and is currently training in the gym 3 times per week. He is trying to gain weight, and is currently eating around 3000kcal per day in order to achieve this.

He should be aiming to consume 1g of protein per pound of bodyweight. This means that he’ll be eating 180g of protein per day. Since 1g of protein contains 4kcal, this means that Brendan will eat 720kcal of protein per day.

From our article on carbohydrates, we also know that Brendan needs to eat between 1g and 3g of carbs per pound of bodyweight. Since he trains 3 times per week and is moderately active at work as well, we’re going to say that he needs 2g of carbs per pound of bodyweight. This means that he needs 360g of carbohydrates per day. Like protein, 1g of carbohydrates contains 4kcal, so Brendan will eat 1440kcal of carbohydrates per day.

Now, we take Brendan’s total daily kcal allowance and remove the calories taken by protein and carbs. 3000kcal − 720kcal − 1440kcal = 840kcal. This means that Brendan has 840kcal left to spend on fats.

Since we know from this article that 1g of fat contains 9kcal, we can divide 840kcal by 9 to work out exactly how many grams of fat Brendan should aim for each day. 840kcal ÷ 9 = 93g. So Brendan should aim to eat 93 grams of fat per day.

I know this is quite a bit of math, but if you want to optimize your progress in the gym, it’s 100% worth it!

Bad fats – the fats to avoid

I don’t like thinking about foods as either “good” or “bad,” as nutrition tends to be a little more complex. However, when it comes to fats, the science is very clear. Hydrogenated fats and their offshoot, trans fats, are definitely bad for your health.

These fats are made by artificially adding hydrogen atoms to unsaturated fats in order to make saturated fats, which have a longer shelf life. This process is known as hydrogenation.

Hydrogenated fats have been linked to long-term heart issues and strokes, as well as to increasing levels of low-density lipoprotein (LDL, or “bad” cholesterol, if you will). Not only that, but trans fats have been linked to increased bodily inflammation.

Your best bet is to avoid any products that have the word “hydrogenated” anywhere on them. Mass-produced baked goods and fast food often contain hydrogenated fats. Luckily, an FDA ban will come into effect in the United States in 2018, preventing the use of these oils in foods.

We’ve finished chewing the fat

Alright! That’s pretty much all I’ve got to say about fats for now. If you’ve stuck with me through the entire article, then you’ll know all about what fats are and which foods contain them. You’ll also know the difference between good and bad fats, as well as how much fat to include in your daily diet to maximize your health and performance.

Have you worked out how much fat you need each day yet?