There seems to have been a lot of conflicting advice recently about the role cholesterol plays in the risk of heart disease and stroke, as well as the role diet plays in our cholesterol levels. Cholesterol-lowering medication can be a source of confusion too – when is it recommended and what other proven measures can we take to ensure healthy cholesterol levels? Here we cover some cholesterol basics and discuss some simple tips for keeping it in the healthy zone (including how to lower your cholesterol by eating more…)
What exactly is cholesterol?
Cholesterol is a waxy, fat-like substance made in the liver that our bodies need for essential things like building cell walls, making certain vitamins such as vitamin D, and hormones such as oestrogen and testosterone. Around 80% of the cholesterol in our bodies is made by the liver, with about 20% coming from what we eat.
What do we mean by “good” cholesterol and “bad” cholesterol?
Cholesterol can’t travel around the body by itself, so the liver packages it up in proteins, known as lipoproteins, which can move the cholesterol through the bloodstream and deliver it to where it’s needed. These are known as low density lipoproteins (LDL) and high density lipoproteins (HDL). These are what is measured when you have a cholesterol test.
LDL particles move the cholesterol from our blood into our tissues, including the cells of our artery walls. Too much of this type of cholesterol can be associated with the formation of plaques in the artery walls, also known as “hardening of the arteries”. These plaques can narrow the artery, reducing the blood flow to essential organs such as the heart or the brain, as well as throw off clots that can lead to a sudden blockage of the blood flow – leading to a heart attack or stroke. Easy to see why LDL is known as the “bad” cholesterol.
HDL particles tend to “mop up” excess cholesterol in the tissues and blood stream and return it to the liver to be cleared as waste. No wonder they’re the good guys! High levels of this form of cholesterol are very protective against heart disease and stroke, whilst low levels can increase risk.
The other types of fat we measure in a cholesterol test are known as triglycerides. Triglycerides are the most common type of fat in our bodies and their job is to convert any excess calories we eat into fat to be stored away for a rainy day (the famine that we are unlikely to ever encounter!). High levels of triglycerides can also contribute to plaques in the arteries; another potential bad guy to keep an eye on.
When should I get my cholesterol levels checked?
The Australian Heart Foundation recommends all adults should have their cholesterol checked regularly from the age of 45. This age may be lower in the presence of other risk factors such as a family history of high cholesterol or heart disease, being Aboriginal or Torres Strait Islander, type 2 diabetes, smoking or being overweight and so on. Your GP can help you decide when you should have a cholesterol test.
What can I do to improve my cholesterol?
There are some causes of unhealthy cholesterol levels that we can’t change such as age and family history. But there are a number of lifestyle factors we can control which not only help our cholesterol levels, but also reduce the other risk factors for heart attacks and strokes:
- Increase your level of physical activity. 30-40 minutes of moderate exercise (such as walking) most days of the week can increase your HDL levels.
- Eat more (yes more!) of certain foods: more fibre such as wholegrains, beans, fruit and vegetables and more healthy fats such as those found in olive oil, avocados, seafood, eggs, nuts and seeds.
- Eat less unhealthy fats such as saturated fats and trans fats found in many processed foods such as pastries and baked goods, fried foods, fatty red meat and processed or cured meat.
- Eat and drink less sugar – excess sugar, including in things like white bread or soft drinks and fruit juice, can increase triglyceride levels.
- Maintain a healthy weight – if you are overweight, even a modest weight loss of 5-10% can significantly improve your cholesterol profile.
- Quit smoking. Smoking (and vaping) lowers HDL levels.
- Drink in moderation. A little red wine may (studies are mixed) be good for your HDL but too much alcohol can lower it and raise triglycerides.
What about medication?
With lifestyle changes, many people can improve their cholesterol levels by about 20%. Sometimes this isn’t enough to get a very risky profile into the healthy zone and cholesterol-lowering medications may be recommended; the presence of other risk factors also goes into the decision-making process.
These medications are effective at lowering LDL, raising HDL and significantly reduce the risk of heart attack and stroke. They’ve been around for decades now and are safe and usually well-tolerated. They work best when combined with the other lifestyle measures outlined above – starting medication does not mean you can go crazy with the deep-fried Mars bars and hot chips!
If you’ve never had your cholesterol checked, or it’s been a while, now is a good time to see your GP for a chat about your heart health.
Photo by Brooke Lark on Unsplash
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