We know fats make up a large part of our diet, but which ones should we be eating – and which should we avoid? Dr Ali Hasan, Vitality clinical operations director, cuts through the myths to bring you the essential facts you need to know.
Fats are essential for our wellbeing: they’re a key source of energy; they’re needed to absorb vitamins and maintain healthy tissues in our body; and certain fats improve our cardiovascular health and help to thin out our blood. Fat has an important role in the experience of eating too – it can make us feel fuller and helps us to enjoy the feel of food in our mouth.
The basic fats
Fats can be divided into two main forms – saturated and unsaturated. Most fatty foods contain a mixture of both. The term ‘saturated’ refers to the chemical structure of the fats – saturated fats are typically solid at room temperature, and include lard, butter, coconut oil, ghee and the fats found on meat. Saturated fat is linked with raised cholesterol and an increased risk of cardiovascular disease and, in general, we eat more of this than we should – nobody needs to actively try to include more saturated fat in their diet.
The average woman should have no more than 20g a day, while the average man should have no more than 30g. Measuring out these amounts is fiddly, so the best approach is to avoid nutrient-poor fast food, cakes and biscuits, and instead have small amounts of nutrient-rich fatty foods such as cheese, yogurt and meat.
Trans fats are a type of processed fat that are well known to be unhealthy. They’re in foods like pastries, pies and biscuits – look out for ‘partially hydrogenated vegetable fats/oil’ on labels. These fats are harmful and can worsen cardiovascular health, including reducing ‘good’ cholesterol levels, so you should have no more than 5g daily. Fortunately, many manufacturers have removed trans fats from products.
Polyunsaturated and monounsaturated fats, found in plant foods and oils, are both healthy. Monounsaturated fats can help maintain levels of HDL cholesterol, the healthy form that removes dangerous LDL cholesterol from the body. Polyunsaturated fats are needed for essential body functions including blood clotting, and help to make cell membranes and nerve coverings. Try to choose unsaturated fats instead of saturated – for example, dipping bread in olive oil instead of buttering it.
As a general rule, fat should make up about one-third of your daily energy intake from food. Fat is high in calories, which can be bad news for both your weight and your waistline. Just 1 tbsp oil contains 135 calories. So, while some fats do have benefits, they should all be consumed in moderation.
The fat we need more of
Omega-6 fat is found in cooking oils, nuts and avocados, while omega-3 fat is found in oily fish such as mackerel, salmon and fresh tuna, plus some plant foods, including walnuts and linseeds. Omega-3 fat has been linked with a range of health benefits, including a reduced risk of heart disease, Alzheimer’s and rheumatoid arthritis.
Most of us consume plenty of omega-6 fat, but very little omega-3. Omega-6 isn’t detrimental to your health, but having too much compared to omega-3 can raise the risk of internal inflammation, which is connected with health problems including heart disease and type 2 diabetes. To correct the balance, make sure you have sufficient omega-3 in your diet – you should eat at least two portions of fish every week, one of which should be oily fish. Pregnant women or those trying to conceive shouldn’t eat more than two portions per week of oily fish, as they may contain low levels of pollutants that can be harmful to a developing baby’s central nervous system. All other adults can have up to four portions of most oily fish every week.
Reading labels is an important way to help control your fat intake. Try to mainly choose foods low in total fat and saturated fat, although be aware that some low-fat or fat-free foods can have more sugar added to compensate. You’ll also need to take into account any food you eat that isn’t pre-packaged – for example, meat from the butcher, takeaways and restaurant meals.
The latest thinking
In recent years, the established link between fat, obesity and cardiovascular disease has been challenged. High-fat diets (such as the Atkins diet) have helped some people lose weight. And recent reports have questioned whether saturated fat really raises the risk of cardiovascular disease – some experts believe high cholesterol may be less important as a marker of heart risk than was once thought. Other research has suggested that full-fat dairy may actually be cardioprotective – instead, some scientists suggest, it’s high-carbohydrate foods that are behind the rise in obesity, type 2 diabetes and heart disease, with our sugar intake a particular culprit.
While excess sugar is certainly harmful, the weight of evidence clearly suggests we should also limit our intake of processed and saturated fat, which most studies have shown push up cholesterol and the risk of cardiovascular disease. Ultimately, it’s not a question of fat versus sugar – too much of either can have a negative effect on your health.
7 ways to reduce fat
- Prepare meals from scratch
- Measure out oil for cooking
- Use a non-stick pan to reduce the amount of oil you need
- Swap cream for low-fat fromage frais or crème fraîche in recipes
- Grill, steam or bake rather than roast or fry
- Remove visible fat or skin from meat
- Grate cheese rather than slicing – you’ll use much less
Concerned about fat? Know your key health numbers with a Vitality Healthcheck.