Fat is often seen as the enemy - from sabotaging our weight loss efforts to blocking our arteries and causing heart attacks. While too much of a certain type of fat may contribute to the risk of heart disease, not all fats should be avoided as they are vital for optimal health. Rather than cut fat out of our diet altogether, we should endeavour to replace unhealthy fats with healthy fats wherever possible.
Types of fat
Fat can be split into three categories, namely saturated, unsaturated and trans fats. Of these, unsaturated fats are the healthy type. Foods high in trans fats should be avoided as much as possible since they are known to raise cholesterol levels.
Foods high in saturated fats include:
pastries, cakes, pies, puddings, biscuits
ready meals, red meat, sausages, burgers, bacon, kebabs, lamb
coconut and palm oils, coconut cream
dairy produce (cream, ghee, butter, cheese, crème fraiche).
Fortunately, trans fats in the UK have been removed from most products but may still be found in some shelf stable products such as cakes and biscuits. Note that trans fats in red meat are naturally occurring.
Whereas saturated fats are solid at room temperature, unsaturated fats remain in liquid form or soft, making this an easy way of identifying them. Healthy unsaturated fats include monounsaturated fats which are derived from plant oils and polyunsaturated fats, also known as essential fatty acids (EFAs).
Polyunsaturated fats are further categorised into two types of fats called omega-3 found in fish oils and omega 6 which is found in vegetable oils. Since EFAs cannot be manufactured by the body, we must obtain them through our food.
The importance of healthy fats
Healthy fats play an important part of our overall health. Certain vitamins such as A, D and E are fat-soluble, meaning they need fat in order to be adequately absorbed by the body. Healthy fats, as well as providing us with energy, can also help protect against heart disease by lowering high levels of LDL (bad) cholesterol. Omega-3 and 6 fatty acids are important for helping to regulate blood pressure, growth, cell structure and a healthy immune system.
How much fat is healthy?
The government recommends men consume a maximum of 90g of fat per day and women 70g, while adults should consume no more than 5g of trans fats per day. Of this, the NHS advises men consume no more than 30g of saturated fat and women no more than 20g of saturated fat per day and children less than this.
Ideally try including at least 500mg of omega 3 (EPA and DHA) which can be found in a 140g portion of oily fish a week.
Note that calorie wise, all fats are roughly equal with around 100 calories per tablespoon.
Foods with healthy fats
All foods with fat in them contain a mixture of saturated, mono and polyunsaturated fats so choose those with higher levels of healthy fats. When looking for polyunsaturated fats, the richest sources of omega 3 fatty acids are found in oily fish such as salmon, mackerel, sardines, fresh tuna and herring. For those who don't like fish, vegan omega 3 supplements provide an alternative.
Plant-based sources of omega 3 include chia seeds, flax seeds, walnuts and hemp seeds. However, the body needs to convert this source of fat into EPA and DHA and not everyone can do this efficiently. According to the Vegan Society, to obtain enough omega 3 from plants, you'd need to eat 1 tbsp chia seeds or ground flax seeds, 2 tbsp of hemp seeds or 3 walnuts on a daily basis. Good sources of omega 6 can be found in walnuts, flax seeds, pumpkin seeds and vegetable oils such as sunflower, soybean and corn oil.