Following a low fat diet makes sense - this is the part of our food that packs in the most calories - 9 calories per gram compared to 4 per gram in carbs and protein. Low fat diets are also recommended by doctors and nutritionists for health reasons - many people benefit from following an eating plan of this type, particularly if they are at risk of heart disease.

Focussing on good sources for this essential nutrient, such as oily fish, nuts, seeds and oils, will ensure that you stay healthy while still losing weight.