Ask the Dietitian: Fat

Fat is possibly one of the most emotive macronutrients. Compared to its friends, protein and carbohydrate, fat tends to come off as the bad guy. When we think of something that is high in fat there can often be guilt attached. Do we actually need fat, or is it just there to tempt us?

As with most things in life, there is more than one side to the story…

The good side to fat

Some vitamins are only soluble in fat such as vitamins A, D, E and K. Without fat we would not be able to access them and we would become deficient. These vitamins have a wide range of functions within the body from strengthening our immune system, to keeping our skin healthy and maintaining our bones. We do not need to have set amounts of certain foods each day to get enough fat, but including sources of dairy, vegetable oils, nuts and seeds overall in the diet will help us get what we need.

Through eating fat our bodies are also able to obtain essential fatty acids that are needed to help keep our hearts healthy. These are often called omega-3 and omega-6 fatty acids. Good sources of these fatty acids include walnuts (and walnut oil), vegetable oil (rapeseed oil), and flaxseeds. It can also be helpful to look out for products that are fortified with omega-3; for example, some eggs, breads and dairy products will have it added.

Perhaps obviously, fat is also a great source of energy. It has more calories per gramme than protein and carbohydrate. This energy helps to fuel our bodies throughout the day. The negative side of this only comes if, overall, we are having too much energy (from fat, carbohydrate or protein) in our diet as this will then be stored as fat in the body.

The darker side of fat

When we think of the negative side to fat, it is often linked to ‘saturated fat’, where the more positive effects are often from ‘unsaturated fats’. Saturated fat is found in many processed foods such as cakes, biscuits, pastries, as well as in dairy products like cheese and some vegetable oils such as palm oil.

Diets high in saturated fat are linked to higher cholesterol levels and higher rates of heart disease. Most of us would benefit from reducing our intake of saturated fat and so here are some top tips for how to do this:

• Use a rapeseed oil (vegetable oil) or olive oil when cooking rather than butter.
• Grill, steam or roast food rather than frying, with a small amount of oil.
• Reduce processed high fat snacks in the diet. Replace these with wholefoods such as nuts and seeds for some unsaturated fat, or some fruit and vegetables.
• When using cheese in cooking, consider using a smaller amount of a stronger cheese e.g. extra mature or a reduced fat version.

In summary, fat is certainly not evil and we need it in our diets. However, most of us need to be careful with the amount of saturated fat we eat.