Often mislabelled as 'bad for you' – fat is a vital macronutrient our bodies need for good health. It builds cell membranes, makes nerve tissue and hormones, and aids the absorption of fat-soluble nutrients, including vitamins A and D. Our bodies also convert it to energy and store it for future use.
Those following a low-fat diet may experience vitamin deficiencies, poor brain function, hormonal imbalance and issues with weight management.
Although eating too much fat can be unhealthy, there are certain types of fat we must get from our diet because they’re essential to our health.
What are the different types of fat?
There are three main types of fat – saturated, monounsaturated and polyunsaturated – and they all play different roles in the body.
Frequently vilified, having been associated with cardiovascular disease and high cholesterol, saturated fat is found in red meat, butter, cheese, burgers and sausages as well as ghee, coconut and palm oil.
A diet high in these fats has historically been associated with an increase in blood fats, including triglycerides, as well as an increased risk of obesity, heart disease, type 2 diabetes and stroke. More recent studies, however, are now suggesting that some fats such as those found in fermented dairy such as cheese, kefir and yogurt do not appear to be as harmful, and may in fact have a positive effect on heart health. This may be because other nutrients in dairy, like calcium, or the fermentation process itself, may modify the effects of saturated fats in the body.
To find out more, read our expert guide on saturated fat.
Monounsaturated fat, like that found in olive, groundnut and cold-pressed rapeseed oils, nuts (such as almonds, cashews, hazelnuts, peanuts and pistachios), olives and avocados are particularly good for heart health. These fats may help manage cholesterol levels.
Polyunsaturated fats are found in corn oil, sunflower oil, nuts and seeds (such as walnuts, pine nuts, sesame seeds and sunflower seeds). There are two main types of polyunsaturated fats: omega-3 and omega-6. These are termed 'essential fats' as they cannot be made in the body and need to be obtained through the foods we eat. Polyunsaturated fats may help to prevent your arteries becoming blocked and may lower blood pressure.
Typically, we obtain a high proportion of omega-6 fatty acids in our Western diet and low levels of omega-3. But, it is important that we eat adequate amounts of omega 3 – key foods are oily fish, such as salmon, herring and sardines, as well as nuts such as walnuts, and seeds such as chia and flaxseed. If the balance of these fats is in favour of omega-6 fatty acids, then it is likely to promote inflammatory conditions. Discover more sources of omega-3 fats.
Also known as hydrogenated fats, these are usually found in processed foods like pies, pastries and cakes and in takeaways. Trans fats have been linked to high cholesterol levels and an increased risk of heart disease and cancer.
Make sure you read labels on any foods you haven't cooked from scratch, and try to avoid those containing ‘hydrogenated’ oils. For more information on trans fats, visit the NHS website.
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