The key to losing weight is to adjust your energy balance so you take in fewer calories in the form of food and drink than you use up. When this happens, your body makes up the deficit by drawing on fat stores so you lose weight. Eating less fat is one way to reduce your calorie intake because fatty foods are very calorific with 9 calories per gram compared to only 4 calories per gram of carbohydrate rich foods like rice or pasta. Fatty foods like cream and nuts pack a lot of calories into a small volume so they are less filling and easier to over eat than bulkier foods like apples or potatoes.
However this does not mean eating no fat at all, as it would be hard eliminate all fats from the diet and it wouldn’t be good for your health. We all need some fat in our diet to stay healthy. It helps us absorb the fat soluble vitamins A, D, E and K and provides the essential fats the body can’t make that must be supplied by our diet.
WHICH FATTY FOODS DO WE NEED?
There are two types of fat to look for in foods – monounsaturated and polyunsaturated. You’ll know these terms from adverts for spreads and oils, as they are seen as the healthier fats.
Monounsaturated fats tend to come from vegetable sources (olive oil, avocados and nuts) and their oil is generally liquid at room temperature. In moderation, monounsaturates have beneficial effects on blood cholesterol levels.
There are two families of polyunsaturated fats: omega 3 and omega 6. The omega 3 family comes from oily fish like mackerel or fresh tuna and the omega 6 family comes from vegetables and nuts.
Both families are needed for growth, building cell membranes and brain development and to help regulate functions such as blood clotting, blood pressure and immunity. In moderation omega 6 can help to lower blood cholesterol levels and omega 3 fats can help maintain heart health.
However healthier fats are still fats, so weight wise, frying food in olive oil is just the same as frying in lard. Eating less generally and choosing healthier fats when you do eat fatty food is what you should be aiming for.
WHICH FATTY FOODS ARE LESS HEALTHY?
The fats that we should be eating less of are saturated fats. They are of animal origin (butter, lard, fat on meat) and are usually solid at room temperature. Your liver can make cholesterol from saturated fat, so eating too much can raise blood cholesterol levels, which in turn may increase your risk of heart disease.
The healthy recommended daily limits of saturated fat are 30g for men and 20g for women. When you consider that a single serving of chicken Korma could contain well over 20g of saturated fat, it’s not hard to see how you can over do it.
There are some fats that the body does not need, these fats are called Trans Fatty Acids or “Trans Fats” which are found in processed foods, especially cakes, biscuits, pastries and takeaways. Trans Fats are formed when liquid vegetable oils are turned into solid fats through a process called hydrogenation. They have similar effect on blood cholesterol as saturated fats raising levels of bad cholesterol and increasing the risk of heart disease. Gram for gram, Trans Fats appear to increase the risk of Coronary Heart Disease (“CHD”) more than saturated fats, and so may be worse for our health. Apart form the energy they contain Trans Fats have no nutrition benefits at all.
As you can see the idea that all fat in your diet is bad and needs to be eliminated for you to lose weight isn’t strictly true. Simply being conscious about your portion sizes and the types of fat you consume can ensure you maintain a healthy diet full of the good fats you need and none of the weight gain!