In comparison to other macronutrients, fats contain double the amount of calories per gram and therefore double the energy. A single gram of fat contains 9 calories, as opposed to the 4 calories contained in a gram of carbohydrates
Fats cannot provide energy for intense or prolonged activity, they are generally used for low-level exercise like walking or jogging and hence many fitness instructors recommend a training zone where the heart rate stays between 50% and 60% of the Maximum heart rate. At this point the body will utilise around 60% fat and 45% carbohydrate as a source of fuel. This training zone is often referred to as the FAT ‘BURNING ZONE’. Research has shown however that sustained periods of working out in this zone does not improve health or cardio vascular system and is not recommended even for weight loss. Calorific deficit is the best way to lose weight and improve fitness, by burning more calories than consumed. This is why any good instructor will recommend a training zone where the heart rate is between 70% to 80% and 80% to 90%, these are often referred to as the ENDURANCE ZONE and PEAK PERFORMANCE ZONE respectively. Fats are there to provide insulation and protection for vital organs such as the heart, liver and kidneys. It also helps to carry vitamins throughout the body.
Not all dietary fats are the same, as with carbohydrates, there are several different types.
Saturated fats are a major contributory factor in coronary disease, some forms of cancer, diabetes, and other degenerative diseases. They are contained in egg yolk, red meat, butter. Lard cheese and commercially prepares cakes and pastries .A traditional western diet consists of 40% fat on average. The recommended allowance is less than 10%, this along with other factors has lead to an increase in obesity and heart disease in western society.
There are two types of unsaturated fats, Monounsaturated and Polyunsaturated. Monounsaturated fats actually reduce the risk of coronary illnesses and are present in things like olive oil, canola oil, avocados, almonds and pecans but even these in excessive quantities are unhealthy. Polyunsaturated fats, although not as harmful as saturated fats don’t offer the same protection as monounsaturated.
Essential fatty acids:
In recent years, essential fatty acids have received a great deal of media attention. Everywhere we look we’re being told about all the Omega oils 3, 6, and 9. These oils are thought to prevent a range of illnesses and are cardio-protective. Of the three different types, omega 3 and 6 need to be consumed within a healthy diet, but the body produces omega 9. Also known as oleic acid, omega 9 is not technically an essential fatty acid as the body can produce a limited amount, but only when omega3 and 6 are present. If the diet is low in these, then omega 9 becomes an essential fatty acid and needs to be consumed.
Health benefits of omega oils:
Lowers cholesterol levels, thereby reduces the risk of cardiovascular disease
Reduces atherosclerosis (hardening of the arteries)
Reduces insulin resistance, thereby improves glucose (blood sugar) maintenance
Improves immune function
Provides protection against certain types of cancer
Food sources of omega 9 fatty acid:
Olive oil - the best source of omega 9
Omega 3 and 6 can be found in most of the above and also in dark green leafy vegetable, oily fish, pumpkin seeds and walnuts.
Despite being demonised in recent years, cholesterol is required in many bodily functions. There are two main types of cholesterol, LDL and HDL. LDL or Low Density Lipoprotein is referred to as” BAD” cholesterol as it carries and deposits the cholesterol around the artery walls, increasing the risk of heart disease. HDL on the other had, also known as High Density Lipoprotein or “GOOD” cholesterol, acts as a scavenger collecting the bad cholesterol deposits from around the body and transporting it to the liver to be excreted. Many foods contain cholesterol, but it’s the high intake of saturated fats that cause the body to synthesise too much bad cholesterol.