Butter and full fat margarine, even polyunsaturated margarines, have the same calorie content. Butter and margarines have a fat content of around 80%. That means that a 10g serving of butter or margarine, the amount that you spread on your toast, has the same 74 calories and 8.2g of fat. That is the same no matter if the spread is made from animal or vegetable fats.
There will be a difference, however, in the levels of saturated, monounsaturated and polyunsaturated fats – there is over 3 times the amount of artery-clogging saturated fat in butter than in a polyunsaturated margarine.
Increasing the proportion of mono- and polyunsaturated fats to saturated fats in our diets can improve heart health by lowering total cholesterol, decreasing ‘bad’ LDL cholesterol and increasing ‘good’ HDL cholesterol. Be careful however that the polyunsaturated fat you choose does not contain trans fats, which can be equally detrimental to your heart health.
Calorie content of margarines will only decrease as the fat content decreases. A serving of a 70% fat margarine will have 64 calories, a 60% margarine gives 57 calories in a serving, a 40% spread has 40 calories per serving, there are 25 calories in a serving of a 25% fat spread and only 10 calories in the same serving of a very low fat, 5% spread.
If you want to decrease your calories, you need to choose a low fat spread, preferably one rich in mono- or polyunsaturated vegetable fats.
Thanks to tescodiets.com who have provided this article.