Nutritional Advice - Fats Explained!
What Are Fats?
Fats are a macro nutrient, this means that without them your body will not be able to function properly. Aside from carbohydrates, fats are a source of energy for your body. When exercising after carbohydrate energy has been burnt off / used up, then the body will start transferring fat into glycogen, which consequently provides energy for the body. Some people think all fats are bad, but they are integral for the correct function of your body. Fats will keep your skin and hair looking healthy, help absorb vitamins and minerals which are fat-soluble (can be broken down by fat) and most crucially fat acts as insulation for your body to help you keep warm.
The fats your body gets from foods provide your body with essential fatty acids. The two main fatty acids required by the body are; linoleic and linolenic. (No spelling mistake, they are seriously different acids, just spelt one letter differently!) Your body needs these acids for many things including; controlling inflammation, blood clotting and brain development. Each cell in the body has some fat within it, this is stored within the cell membrane. Fats many many other uses around the body, hormones are also made from fats.
Each gram of fat contains 9 calories. This works out to be just over two times more than other key macro nutrients carbohydrates and protein, which both contain 4 calories per gram. So twice as many calories per gram! Amazing! No wonder they are called, 'fattening!'
All fats consist of saturated and unsaturated fatty acids. A fat will be determined as a saturate or unsaturate depending on the amount of each specific type of fatty acid they consist of. Fatty acids are produced when the fats are broken down inside us. The fatty acids are considered to be, 'good fats.' These acids are not greatly soluble in water and can be used for energy by the majority of cells within the body. They offer many healthy benefits to the body, however over consumption can lead to negative effects. It is important to realise that not all fats are bad for us, and that many fatty acids have positive effects. Remember fats are essential for our bodies to function in the correct manner.
Types of Fats?
Primarily there are three different types of fats, excluding trans-fats which we will explore later. The three fats consist of two unsaturated fats called polyunsaturated and monounsaturated, and the other types is saturated fats. Fats will influence your hormonal production levels. Roughly twenty percentage of your daily calories should come from good fats. If you have any less then this your hormonal production will go down. Any more than this, and you will start gaining weight through becoming fatter.There are huge differences between each of them, as will be explained.
The three fats vary because the molecular structure varies, without going into too many boring details, a type of type is determined by the number of double bonds that exist within its' molecular structure. A scientifically engineered fat will contain other variations of bonding, these are known as isomers. Such as trans-isomer. (commonly known as trans-fat)
Saturated fats - Saturated fats are usually found in large quantities in animal origin products. This type of fat is proven to increase you cholesterol level. Having a high cholesterol will put you at risk of serious medical issues, such as; heart attacks, stroke and atherosclerosis. Cholesterol, for those who do not know, is a soft waxy substance that can block and clog vital arteries around your body. Ideally you will want to limit the amount of saturated fats which you eat.
Here are some examples;
- Fatty Meats
- Dairy Products
- Coconut Oil
Ideally only ten percentage of your total calorie intake for one day should consist of saturated fats.
Polyunsaturated fats - This type of unsaturated fat has no affect on cholesterol. It is found in foods such as;
- Leafy Greens
Polyunsaturated fats usually have a higher level of good fatty acids, such as Omega-3 and Omega-6, which may reduce the risk of cardiovascular disease.
Monounsaturated fats - These fats are high on essential fatty acids. They have a positive effect on cholesterol by lowering the levels within the arteries. They can be found in mostly natural foods, such as;
- Red Meats
- Whole Milk Products
A great example of a monounsaturated fat is olive oil, which contains about 75% monounsaturated fat. Others examples include canola oil which is roughly 57%-60%. Although monounsaturated fats have been proven to have a positive link with breast cancer. It is recommended that 10-15% of your daily calories should come from monounsaturated fatty acids.
There is one fat style which everyone seems to be talking about avoiding... This is the infamous trans-fat! Trans-fat is a scientifically engineered fat which has been through a process called hydrogenation. This allows the fat is remain solid at room temperature. Trans-fats are used primarily to extent the shelf life of various food products, it is a much cheaper alternative when compared to other fats. There is minimal positive fatty acids within this kind of fat. It is proven to increase cholesterol dramatically. This is the kind which should be avoided at all costs. Foods which may contain a high level of trans-fat include;
- Processed Foods
- Fried Food
- Any Fast Food
However, trans-fat can be found naturally in milk and some body fat of ruminants, for example, cattle and sheep. The naturally occurring trans-fats has a higher nutritional value then the modified oil trans-fats, with acids such as conjugated linoleic acid (CLA) and vaccenic acid. However the National Academy of Sciences advises that, "trans fatty acids are not essential and provide no known benefit to human health." Any intake of trans trans-fats will increase your cholesterol and increase the risk of coronary heart disease at the same time.
There are numerous of health issues which have been related to trans-fats. Here is a list of the main ones;
- Alzheimer's Disease - A study from the Archives of Neurology published in February2003 found links between the consumption of trans-fat and the promotion of Alzheimer's disease. It has been found that trans-fats impaired memory and learning capabilities in middle aged rats. The rats showed an increase in inflammation around the hippocampus, this is the area of the brain which is responsible for learning and memory. The same inflammation which is found in adult people with Alzheimer's disease
- Diabetes - The risk of type 2 diabetes is increased with the more trans-fats you consume.
- Obesity - It is obvious too much consumption of any fat will make you obese, but trans-fats have a larger potential to allow you to gain weight rapidly. Obesity in itself comes with a great number of other unrelated health issues.
- Liver Dysfunction - Trans-fats are metabolized differently by the liver more so than other fats, this increase the risk of developing liver dysfunction.
- Infertility in Women - Consuming too many trans-fats will increase the risk of ovulatory infertility. A UK study in 2007 confirmed this.