Fats and Oils
Fats and oils make an important contribution to adequate nutrition, they are a source of energy for the body, they insulate and protect the body’s vital organs, they are a source of essential fatty acids and they are required for the absorption of the fat soluble vitamins A, D, E and K.
The most obvious and defining difference between fats and oils is that fats are typically solid at room temperature whereas oils are liquid at room temperature.
Fats and oils enter our diet through a variety of sources; dairy products, and meat, fish, poultry and seafood are all sources of fats, and some vegetable and plant foods are sources of oils.
Fats and oils also enter our diet through many of the products we add to our foods to aid cooking or to simply make them more ‘palatable’. Such additions include; butter, margarine, lard, mayonnaise, ghee and cooking oils.
Dietary fats and oils are a concentrated source of energy when compared to carbohydrate and protein, having over twice the amount of calories per gram. So because fats and oils so energy dense we don’t have to consume much of them to tip the energy balance scales into the positive and gain weight.
Did you know that 80% of diabetes is attributed to having a higher than normal Body Mass Index (BMI) which indicates simply that the energy balance scales are tipped excessively towards weight gain – i.e. too many calories are being consumed and not enough are being burnt off through activity?
This is a major reason why most national nutritional guidelines recommend increasing physical activity and reducing fat intake as their studies simply show that we are eating too many calories, especially fat calories, and not exercising enough (if at all) and consequently gaining excess weight (often rapidly).
All fats and oils are a mixture of saturated and unsaturated fatty acids. The differences in physical properties between one fat and another are due to the fatty acids they contain. The structure of the fat molecule determines whether a fat is classed as saturated or unsaturated. Unsaturated fats (fatty acids) are further divided into mono-unsaturated and poly-unsaturated fatty acids.
Saturated fats are predominantly found in animal products namely meat and dairy foods, while unsaturated fats are predominantly found in plant based foods.
In relation to understanding fatty acids we also need to understand cholesterol and lipoproteins.
Cholesterol is found in many foods of animal origin and is rarely found in plant foods. Thus cholesterol is highly associated with the saturated fatty acids found in meat and dairy foods. If there is a surplus of cholesterol in the blood it can be deposited as ‘plaque’ on the walls of our arteries which can lead to a narrowing of the arteries, angina, heart attack and stroke.
In fact high total blood cholesterol which reflects a high saturated fat intake is attributed to over 70% of the premature deaths from stroke and heart disease. So helping your personal training clients to reduce their saturated fat intakes will not only help them reduce their caloric intake but also improve their longevity and quality of life!
In our bloodstream fats are transported by lipoproteins. Two key lipoproteins are high density lipoproteins (HDL), and low density lipoproteins (LDL). LDL’s contain large amounts of cholesterol and carry it through the blood to deposit it in the cells. HDL’s pick up the cholesterol and carry it back to the liver for processing and excretion.
So to help improve your clients (and your own) cholesterol situation we can encourage clients to reduce their LDL intakes by altering the types of fats and oils they consume. Encourage your clients to choose low fat in the dairy isle, to pick lean meat, to remove the visible fat around meat, and to avoid cakes and pastries made from butter.
As well as encouraging clients to make these changes we should also ensure they increase, or at least sustain their intake of HDL’s so that cholesterol is transported to the liver and excreted rather than forming plaques on arterial walls.
One way of doing this is encouraging clients to eat foods that are higher in unsaturated fats as opposed to foods high in saturated fats. This is one reason many countries recommend eating more oily fish as well as more plant and vegetable foods which are higher in unsaturated fats and HDL’s.
Takeaway food is typically high fat food (often saturated) and it seems we are eating more and more of it. Just check out how many fast food outlets there are in your town now as opposed to 10, 20 or even 30 years ago. The growth in the fast food industry is phenomenal (and terrifying from a health perspective)
So another meaningful change we should encourage in our personal training clients is the reduction of high fat takeaway food, especially burgers, pizza, fried chicken and ‘fish n chips’.
Interestingly a study in New Zealand showed that the discretionary additions of fat to food contributed 22.5 % of the total fat intake of New Zealanders. This statistic will likely be very similar in all western countries. So in many cases changing a client’s fat in take from unhealthy to healthy can be as simple as helping them focus on reducing and/or eliminating the unnecessary additions of butter, margarine and mayonnaise to food.