This Nutrition Nibble on Lipids encompasses both Fats and Cholesterol which have a bit of a bad name in today’s society. People are always on the lookout for low-fat, no-fat, reduced- fat, fat free, cholesterol free foods. Many people are under the asumption that cutting fats and cholesterol from our diets completely could be the way to optimum health. This, however, is not the case.
The biochemical basis behind lipids can be quite complicated so I’ve tried to keep it simple and stick to a basic overview to help you weigh up the options when choosing your own foods.
Fats are visible and invisible in the foods that we eat, and even though there are many positives to lipids there are still good and bad fats. On the whole though, lipids are important for our nervous system and brain function. Fats are one of our primary forms of energy and can be burned to make energy. They assist vitamins to enter our cells and help in the formation of steroids and cholesterol as well as being an essential component in our cell membranes. Fats are one of the means of transportation for the cells around our body and protect our internal organs from damage.
Fats are insoluble in water so our bodies take special care to break them down and then transport them to our cells. If our body is working well though, this isn’t a problem.
There are a couple of types of fats/lipids that we need to be aware of:
Saturated Fats / Trans fatty acids – the “bad fats”
Saturated fats are found in animal products such as beef, butter, whole milk and cheeses. Think of the fat on the side of a rump steak. Saturated fats aren’t found in many plant products with the exception of palm and coconut oil which are very high in saturated fats.
Saturated fats are the ones that aren’t particularly good for us. In chemical terms they have molecules that stack closely together making them solid at room temperature. Too many saturated fats in the diet can lead to heart disease and high blood pressure. Some studies have shown that breast, colon and prostate concer are all linked to diets high in saturated fats. Saturated fats will be found in many of your takeaway foods including thai dishes that use coconut cream or oil. Saturated fat though, like all fats, do play a part in cell membrane structure and energy production.
Trans fatty acids are the ones to definitely stay away from as they are definitely no good for our system and come mostly from take away foods (like fast foods and hot chips) and other processed foods (like margarine). Trans fatty acids have been shown to raise your bad cholesterol whilst lowering your good cholesterol which makes them destructive whatever way you look at it.
Monounsaturated and Polyunsaturated Fats – the “good fats”
These are what are commonly known as the “good fats”. In chemical terms, these fats contain molecules that cannot pack closely together due to their structure making most of them liquid at room temperature.
These fats include vegetable oils (avocado, olive and peanut), cashews, almonds, peanuts and avocados.
Polyunsaturated fats are found in vegetable oils and fish. Due to their structure, these fats are susceptable to oxidation – much more than saturated fats. I’m sure you’ve all had the experience of eating a nut that is terrble tasting and is one that you just have to spit out! This is because the nut has oxidised. Oxidised foods/oils aren’t good for our insides as they will increase the oxidants and free radicals in our bodies which isn’t a good thing.
On the upside, mono/polyunsatruated fats will:
• Enhance good cholesterol • Lowers blood pressure • Reduce blood clotting • Resuce the risk of gallstone formation when replacing saturated fat
The KING of unsaturated fats is OLIVE OIL. It has been shown to lower your bad cholesterol and raise your good cholesterol at the same time. To reap the full benefits of olive oil it should be used straight from the bottle on your salads and vegetables. Like all unsaturated fats it will quickly oxidise upon heating so it should not be heated to a high temperature.
As unsaturated fats oxidise with heat and light it is a good idea to keep your vegetable oils and nuts in dark coloured jars in the fridge to extend their life.
Cholesterol is vital to the overall health of our system. We get cholesterol from the foods in our diet such as eggs, meats and animal fats. Cholesterol is also made in our bodies by the liver. Even if you are a vegan who doesn’t get cholesterol from the diet, your liver will still make enough to support your bodily functions.
Cholesterol is required to:
• Build and maintain cell membranes • Aids in the manufacture of bile which helps digest fats • Important for the metabolism of fat soluble vitamins inc Vitamins A, D, E and K. • Is a precurser to the production in the body of Vitamin D • Involced in the production of various steroid hormones in our body including the male and female sex hormones • Important role in the immune systems Most people are aware of “good” and “bad” cholesterol. Good cholesterol, known as HDL, is responsible for transportation of cholesterol to and from the liver. Having a high level of HDL is shown to be beneficial to our overall health.
Bad cholesterol, known as LDL, is responsible for the clogging of arteries and gallstones, which are 100% pure cholesterol.
The important point with cholesterol is to know your levels of HDL and LDL levels because this is what’s important. Some people can have quite high cholesterol levels but actually have low LDL levels which means that there over all health is probably ok.
So that is lipids and fats in a nutshell. Instead of getting stressed about eating fats and cholesterol try and think about the “type” of fats and cholesterol that you are eating because this is the most important point.
Remember that everyone falls off the wagon once in a while so a week of eating hot chips and mayonnaise can be rectified by a week of being careful about what you put into your system.
Your body is your most important asset Take care of it!