High fat intakes can lead to distortion of the energy balance equation such that if calorie intake exceeds expenditure then the risk of obesity increases. It is well established that obesity is a risk factor for cardiovascular disease, type II diabetes, hypertension, cancer and stroke. However, beyond energy intake, the quality of fat seems to be far more important in terms of determining risk of disease, than quantity.
A large body of research exists to help explain the health effects of particular fatty acids. Saturates, the ones to watch, have been identified as those fats which carry the biggest health risk. Diets high in saturated fatty acids have been found to increase LDL ("bad") cholesterol, which forms plaque and collects in the artery walls, restricting blood flow, raising blood pressure and increasing the chance of developing coronary heart disease.
Recent evidence has found replacing saturated fatty acids with monounsaturated fatty acids and polyunsaturated fatty acids in the diet can be effective in reducing cholesterol levels and hence helping to reduce the risk of heart disease. Recent analysis of published research has indicated benefits of diets high in monounsaturated fatty acids that go beyond heart disease.
Health effects associated with a Low Fat Intake
Some fat in the diet is important - it is an essential nutrient afterall. Fat is also important for palatability. Extremely low fat diets would likely limit the amount of fat-soluble vitamins and essential fats in diets and would result in a diet so bulky that overall nutrient intake might be compromised. Extremely low fat diets might compromise essential fatty acid status too although this is very rare.
