The Truth About Fat

The Truth About Fat

Fat is one of the most misunderstood aspects of nutrition.

Many people try to avoid fat in their diet, even opting for “low-fat” or “fat-free” versions of their favorite foods. Many times, these very same people are the first to gain even more body fat.

Why is this?

Because they need fat to lose fat. We all do.

What is Fat?

Fat is your body’s secondary source of energy, after carbohydrates. Fat regulates your body temperature and acts as insulation for your vital organs. It allows vitamins A, D, E and K to absorb into your body. Healthy fats contain omega-3, omega-6, oleic acid, and linoleic acids, which are literally the food for your brain.

Healthy fats take longer to digest, they keep you feeling fuller, longer - helping you stick to a calorie deficit if you’re trying to lose weight.

If fats are so great for us, why do they have such a bad reputation?

Because there is a big difference between eating the healthy fats your body needs to function, and the bad fat that your body can’t break down - yet most people lump all fats into the same category - the bad one. It makes sense, when many people eat a poor diet filled with packaged convenience foods and take away.

Let’s take a look at what types of fats to indulge in and what types to avoid - but when it comes down to it, eating a well balanced diet full of fresh natural food, is a fool proof way to ensure you are choosing more healthy fats and less bad fats.

Types of Fats

The easiest way to differentiate healthy and unhealthy fats is their solidity. Imagine cooled bacon fat - now imagine that fat inside your bloodstream. Your body has a much harder time breaking down solid fat and removing it from your blood.

This is what causes high bad cholesterol and clogged arteries, increasing risk of heart attack and stroke. You want to limit the amount of solid fat stored in your body so your body can deal with it appropriately.

Fats that are liquid at room temperature are healthiest.
Fats that are solid at room temperature should be limited.

Scitec infographic of sources of healthy and unhealthy fats

Indulge: Unsaturated Fats

Unsaturated fats are liquid at room temperature, making them the healthiest of all the fats. There are two types of unsaturated fats, and both have different nutritional benefits:

Monounsaturated Fats

These unsaturated fats raise HDL (good cholesterol) and lower LDL (bad cholesterol). HDL carries excess solid fats in your bloodstream back to your liver to be disposed of. HDL is essential to maintaining a healthy balance of cholesterol.


  • Avocado
  • Extra Virgin Olive Oil
  • Canola Oil
Polyunsaturated Fats

In addition to improving cholesterol like their monounsaturated counterparts, polyunsaturated fats contain Omega 3 and 6 fatty acids - the two essential aminos you can only get from your diet. These acids have anti-inflammatory effects and can help prevent heart disease, diabetes and some cancers.


  • Nuts and seeds
  • Vegetable oils like corn and safflower oil
  • Fatty fish like salmon and tuna

Limit: Saturated Fats

Saturated fats are solid at room temperature and are mainly found in animal sources like meat and dairy. These fats can still be part of a healthy balanced diet, but should be eaten in moderation.


  • Whole milk dairy like cream, cheese, butter
  • Limit fattier cuts of meat like bacon, t-bone steak, chicken skin (choose lean meats like skinless chicken breast instead)
  • Processed meats like sausages, pepperoni, salami
  • Coconut oil and palm kernel oil

Avoid: Trans Fat

While technically an unsaturated fat, trans fat is solid at room temperature which means it gets a category all on it’s own. Although it can be found in some animal products in trace amounts, it is mainly created in a process called hydrogenation - where hydrogen is pumped into a vegetable oil to create a solid fat similar to a saturated fat.

Trans fat raises your bad cholesterol and lowers your good cholesterol, which leads to more solid fat in your blood.

Even if your food choice contains minimal amounts, every bit of trans fat adds up. In the UK, manufacturers are not required to list trans fat on their food label. What makes this fat so dangerous is the fact that much of the time you’re not aware of the ingredient.


Many, if not most, packaged foods contain trans fat. You can bet the muffins, cookies, cakes, icings, frozen pizzas, biscuits and other doughs in the grocery aisles all contain some amount of trans fat. Fried foods, whether frozen or take away, are another common source of trans fat.

Check the label for clues to hidden trans fat. If you see any of these words in the list of ingredients, it contains trans fat - even if the nutritional label shows none:

  • Hydrogenated
  • Partially hydrogenated
  • Shortening

How Much Fat?

Now that you know what kind of fats you should be eating - let’s take a look at how much fat to eat.

Understanding calories helps you choose the right servings sizes to stick to your goals.

There are three types of calories, which simply put, are your body’s only sources of energy. These are also known as the three macronutrients.

Carbohydrates, Protein, Fats

Carbohydrates are your first source of energy, metabolising into sugars in your blood and used as fuel. Once you’ve depleted your carbs stores, your body uses fat as it’s secondary source of energy. Protein is mainly used to repair and rebuild your physical body - cells, muscles, skin and bone.

A common misconception about fat is that all calories are equal. Because fats are more dense, they account for more than double the calories per gram than carbs or protein - fats are worth 9 calories per gram, where protein and carbs are worth 4 calories.

Let’s say you’re eating a piece of cake with 20g of fat per serving - that is a whopping 180 calories just from fats - or 30% of your daily value. The same size serving of protein would be 84 calories, or 15% of your daily value.

Watching your fat intake is important - you want to keep your ratio of fat in check, since the calories from fat can quickly add up.

For a standard balanced diet based on 2,000 calories, approximately 30% of your calories should come from fats:

Scitec graphic showing macronutrient split based on a 2,000 calorie diet

Your ratio of fats you should have in your diet may need to change depending on your goals and your body type. For some people, eating a higher ratio of healthy fats can actually help you lose fat.

Check out our article on body types to figure out which category you fall into. Each body type has a different metabolism which dictates your ability to process carbohydrates. When you have a harder time processing carbs, your body has an easier time metabolising fats.

If you’re prone to weight gain and find it hard to lose fat, you will likely benefit from more fat in your diet - and less carbs. Knowing how to feed your body based on your individual metabolism is a game changer to your nutrition and makes a huge difference to reaching your goals - and for your overall health.

Fat for Your Body Type

Scitec graphic showing amount of fat per body type


Ectomorphs have a very high metabolism and they process carbs very quickly. A high carb tolerance means they should eat more carbs for energy, and only 20% of calories from fat.

Ectomorphs find it hard to gain weight, have naturally lean muscle and a thinner bone structure.


Mesomorphs have a moderate metabolism and carb tolerance. This is why the mesomorph should  eat a balanced diet, with 30% of calories from fats.

Mesomorphs gain weight and muscle easily - and can lose fat and muscle just as easily. They usually have a stockier build with broad shoulders - most bodybuilders fall into the mesomorph category.


Endomorphs have a slower metabolism and a low carb tolerance. Because they have a hard time metabolising carbs, the blood sugar is not used as energy and ends up being stored - this is what causes weight gain. Due to your low carb tolerance, you should eat around 40% of calories from healthy fats and limit carbs.

Endomorphs gain weight and find it harder to lose weight. They usually are shorter, and have a rounder body shape with weight carried on the stomach, thighs and butt.

Best Times to Eat your fats

The rule of thumb is to eat your fats earlier in the day because fats take longer to digest. Your metabolism slows the later it gets, and it’s the slowest during sleep. If you eat high fat foods at night, you’re not going to have time to metabolise the calories and instead they are stored.

Eat healthy fats like avocado with breakfast, and keep fats to minimum at dinner. Avoid late nights snacks like chips and pastries.

You Need Fat

Everyone needs fat in their diet - it’s just a question of what type of fat and how much. Fats that are liquid at room temperature are the healthiest fats.

The biggest part of your daily fat intake should come from unsaturated fats. Include lots of nuts, seeds, fatty fish, olive or other vegetable oils, and avocado in your diet.

Limit solid saturated fats. Choose leaner cuts of meat and remove skins. Avoid processed meats like sausages and deli meats.

Your body has a very difficult time processing trans fat and they are best avoided completely. Pay attention to the labels on packaged and frozen foods and avoid hydrogenated ingredients.

Find your body type to determine the best ratio to eat in your diet. If you have a hard time gaining weight, eat less fat and more carbs. If you gain weight easily and have a hard time losing weight, eat more fat and less carbs. If you want to maintain your weight, eat a balanced diet.

For a full understanding of calories, check out the rest of our articles in the Macronutrients Series: Carbohydrates and Protein.