They are essential when you consume them ... in balance!
Fats and cholesterol are essential nutrients that perform a number of important functions in our body.
These include giving our cells their structure, being a source of energy, and transporting vitamins throughout the body.
The foods we eat contain different types of fats. The healthiest fats include monounsaturated fats and polyunsaturated fats (omega-3 and omega-6). The least healthy fats are saturated fats and trans fats.
Cholesterol is an important type of fat that is carried in the blood. Approximately 75% of the cholesterol in our body is produced by our liver. The rest, about a quarter, comes from the food we eat.
Fats, cholesterol and our health
Both saturated fat and trans fat are linked to an increased risk of heart disease and high blood cholesterol (or more specifically, an increase in 'bad' cholesterol - see below).
On the other hand, unsaturated fats - polyunsaturated and monounsaturated - are an important part of a healthy diet. They lower the risk of heart disease and lower cholesterol levels.
What types of cholesterol are there?
There are two types of cholesterol found in our bodies: HDL cholesterol (the "good" cholesterol) and LDL cholesterol (the "bad" cholesterol).
HDL cholesterol helps prevent cholesterol build-up in the arteries.
LDL cholesterol, on the other hand, is the main cause of cholesterol accumulation in the arteries.
Eating too many foods containing cholesterol was once believed to be the main cause of high blood cholesterol. However, today, we know that eating too many foods that contain higher amounts of unhealthy fats (saturated fats and trans fats) is a bigger problem and has a much greater effect on unhealthy cholesterol (saturated and trans fats).
Polyunsaturated fats3 (Omega-3 and Omega-6)
Almonds, peanuts and walnuts
Vegetable cooking oils (canola, peanuts, sesame olive oil, or sunflower)
Sesame seed spread (tahini)
Flaxseed and Chia
Canola, sunflower, soybean oil.
Pine nuts, walnuts and Brazil nuts
Processed foods such as cookies, cakes, pastries, and takeout
Fat in red meat and chicken
Baked foods such as cookies, cakes, pastries, and muffins
Small amounts are naturally found in dairy products, beef, veal, lamb, and mutton.
Offal (liver, pate, kidney)
* In terms of blood cholesterol levels, cholesterol in food is much less important than eating less unhealthy fats (saturated and trans fats) and more healthy fats (monounsaturated and polyunsaturated fats)
High Blood Cholesterol: Who is at Risk?
High blood cholesterol is a major risk factor for heart disease. Therefore, it is highly recommended that you visit your doctor so that he can discuss ways to reduce the risk of developing high blood cholesterol (or start treatment as soon as possible if necessary).
As we mentioned earlier, eating a diet high in unhealthy fats (saturated and trans fats) is a risk factor for high blood cholesterol.
Other lifestyle factors that are known to increase your chance of developing high blood cholesterol include:
- Obesity: Having a body mass index (BMI) greater than 30
- Large waist circumference: If you are a man with a waist circumference of at least 102 cm or a woman with a waist circumference of at least 89 cm
- Lack of physical activity - Exercise helps increase your good cholesterol levels
- Smoking: cigarette smoking damages the walls of the blood vessels, increasing the accumulation of fat deposits
- Diabetes: High blood sugar can contribute to more 'bad' cholesterol and less 'good' cholesterol
High Blood Cholesterol: Prevention Tips
So what can you do to lower your risk of developing high blood cholesterol (and at the same time lower your risk of developing heart disease and other lifestyle habits?
- Diet: Switch to eating healthier fats instead of less healthy fats. Moderate your total fat intake.
- Exercise: Get at least 30 minutes of moderate intensity exercise every day (or at least most days)
- Stop smoking.
- Set a weight goal: Set a waist circumference (men less than 94cm and women less than 80cm) and a BMI goal (less than 25)
- Limit your salt intake: Aim for less than 4g of salt per day
- Limit your alcohol intake
If you have multiple risk factors or already have high blood cholesterol levels, your doctor may recommend starting lipid-lowering medications (which can lower blood fat and cholesterol levels).
As with all medications, the benefits and risks must be carefully considered.
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Heart Foundation (online). Cholesterol in blood [accessed January 31, 2019].
Mayo Clinic (online). High cholesterol [accessed February 4, 2019].
The Royal Australian College of General Practitioners. Guidelines for preventive activities in general practice. 9th edn, updated. East Melbourne, Vic: RACGP, 2018.