Dietary fats: understanding 'good' and 'bad' fats

Libby Limon BSc NT mBANT / Jul 25, 2016

You might have heard on the nutrition grapevine that ‘sugar is bad and fat is good’. It’s true (mostly) but, like many things, it’s not as simple as that.


Ok, so there are ‘good’ fats, fats that are ‘fine in moderation’ and ‘bad’ fats... then there are fats that can be used for cooking and others that you should only eat cold. Here's our guide on how to get it right. 

Definitely, fat in alone doesn’t make you fat, in fact, often the opposite is true, as they are very satiating. They have many health benefits too, in terms of supporting hormone production, helping mood, focus, and mental wellbeing, supporting the immune system and protecting the heart.

It is important to understand your fats to incorporate them healthily into your diet, so let’s get back to the basics

There are 3 main types of fats;

1. Polyunsaturated

2. Saturated

3. Trans

These refer to how full the fat molecule is with hydrogen ions. A saturated fat is ‘saturated’ or full with hydrogen ions, so no more can be added, this makes it inflexible and likely to be a solid at room temperature. A polyunsaturated fat means that it has number of spaces that hydrogen ions could be added onto, it is more flexible and fluid.

A trans fat is a polyunsaturated fat, which through a heat process has been made more saturated. This is achieved by drawing hydrogen ions from the atmosphere to make an artificially saturated fat. These artificially saturated ‘trans fats’, also called ‘hydrogenated fats’, are slightly different from their natural counterparts such as animal, coconut and dairy fats, therefore the body struggles to recognise or process them. They are the most damaging to health.

Polyunsaturated fats such as seed oils, including sunflower, flax, chia, sesame and walnut, are very beneficial for health, but they need to be produced via a heat-free process to avoid trans fats being formed. Always look for ‘cold pressed and unfiltered’. Due to their instability when heated (if you cook with them) you can create these damaging trans fats. 

Therefore, it's better to cook with:

  • Saturated fats e.g. coconut oil or organic ghee; 
  • More stable vegetable monosaturated oils such as olive, avocado or macadamia.

Polyunsaturated oils from seeds should always be used cold in dressings to confer the health benefits.

There are also some special classes of fat that we know the body likes to use in supportive pathways...


Medium Chain Triglycerides (MCT or MCFA for short). MCTs are a healthy form of saturated fatty acid that has numerous health benefits, related to heart health, obesity prevention, and brain health. MCTs are found in things like coconut oil, organic butter or ghee from grass-fed beef and are easier to digest than long-chain triglycerides (LCTs). They are a preferred energy source for the body and brain after carbohydrates. MCTs are thus a good choice for anyone who has increased energy needs, including those recovering from illness, surgery or fatigue, to enhance athletic performance and to counteract the decreased energy production that results from ageing.

Essemtial Fatty Acids

Essential fatty acids, especially omega 3 and omega 6, are key to a number of areas of the body’s wellbeing. They help regulate the immune system especially your inflammatory response. They also help the fluidity of cell membranes, and so the ability of neurotransmitters to bind effectively, so have been shown to help with mood health, anxiety, and depression. They are an anti-coagulant and increase ‘good’ HDLs and are therefore protective of heart health.

Anthropologically we probably evolved on a 1:1 ratio of omega 3:6 in our diets. Post-agricultural and industrial revolutions, this has dramatically switched in favour of omega-6 and is now closer to 16:1. It is, therefore, important to increase your amount of dietary omega 3. The most effective form to consume is from fish or krill, as these are already part way converted into the form need by the body. For vegetarians and vegans, however, these are unavailable. Plant forms of omega such as chia and flax seed are sources of omega 3, however, the inefficient conversion makes them a much less effective source. For vegans, the most effective way to achieve optimal levels of usable omega 3 is via algae-based supplement.  VITL is proud to offer both sorts of omega 3 supplements for both our vegan and non-vegan customers.

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