A high cholesterol level is dangerous, but with the right diet, an active lifestyle, and support from your doctor, you can get it under control
Most of us know cholesterol is linked to heart health. We’ve probably heard it comes in good and bad varieties.
We may have even been told to eat fewer eggs to keep our levels in check. But do we really understand what cholesterol is and why it’s essential to keep it under control? We turn to the experts for answers.
What is cholesterol?
“It’s a type of fat in our blood that is produced by the liver,” says Dr Angie Brown, a consultant cardiologist and medical director of The Irish Heart Foundation. “Some of it also comes from the food we eat.”
Vincent Maher is a clinical associate professor at Trinity College Dublin and a consultant cardiologist and director of chronic cardiovascular disease at Tallaght University Hospital. He explains what cholesterol does in the human body: “Cholesterol is vital for normal cell function, and you’ll find it in every membrane of every cell. It’s also required to produce certain hormones and vitamin D. We wouldn’t survive without it.”
Problems can arise, however, when cholesterol levels in our bloodstream get too high.
“When cholesterol is elevated, it can be deposited in our arteries,” says Dr Róisín Colleran, a consultant cardiologist with the Mater Private Network in Dublin.
“Over time, this can result in arteries narrowing and becoming blocked, which can lead to cardiovascular disease and heart attack or stroke.”
What is ‘good’ and ‘bad’ cholesterol?
Particles called lipoproteins carry cholesterol around the body because cholesterol isn’t soluble in the bloodstream.
“There are different types of lipoprotein,” says Maher. “There’s low-density lipoprotein (LDL). I tell my patients that L is for lousy, because that’s the one that sticks to artery walls and increases your risk of heart attack and stroke.”
There is also high-density lipoprotein (HDL). “I tell my patients that H is for healthy because HDL helps the liver re-absorb the cholesterol that was stuck in the artery walls back to the bloodstream to be cleared by the liver,” says Maher. “To avoid damage to the blood vessels, you want to keep HDL levels high to help keep LDL levels low.”
What are high HDL and low LDL levels?
Brown says that healthy individuals should aim for a total cholesterol level that’s under five.
“Your LDL should be lower than three millimoles per litre,” she says. “And your HDL should be higher than one millimole per litre.”
Colleran adds that individuals at higher risk are advised to adhere to stricter criteria. “If you’ve got high blood pressure, diabetes, or a family history of heart disease, you should keep your LDL below 2.6,” she says. “If an angiogram or CAT scan has found plaque in your arteries, it should be less than 1.8. And if you’ve had a heart attack or had a stent fitted, you should keep your LDL levels under 1.4.”
What are triglycerides?
Brown also points out that triglyceride levels are typically checked during cholesterol tests and that these should be below two millimoles per litre in healthy individuals.
“Triglycerides are the unused calories that are stored as fat under our skin and around our organs,” says Maher.
“High levels of triglycerides often signify the presence of more dangerous small LDL particles, which can also contribute to the narrowing of artery walls, putting us at increased risk of heart disease.”
How can you tell if your cholesterol levels are too high?
There are often no obvious signs or symptoms, says Maher.“You could be young, slim, physically fit, and eat healthily, and still have high cholesterol. The only way to tell is to have regular blood tests.”
How often should you have these blood tests?
If you have no pre-existing health conditions or family history of heart attack or stroke, Colleran recommends booking your first cholesterol test when you turn 40.
“If it meets all the healthy criteria, then you should get it checked every four to five years or so to ensure it stays that way,” she says.
You should also get your cholesterol checked in the aftermath of any changes in your health. Maher cites going through menopause and being diagnosed with diabetes as two major health changes that can impact cholesterol levels.
Can our genes also have an impact?
Brown explains that cholesterol levels are often genetically determined. If one or both of your parents have high cholesterol, the chances are that you will too. There are also genetic disorders such as familial hypercholesterolaemia. This affects approximately one in every 250 people in Ireland, causing extremely high levels of cholesterol from birth.
“If you have a family history of this disorder or of heart disease, you shouldn’t be waiting until your 40s to get your cholesterol checked,” says Maher. “The sooner it’s checked, the better, as this genetic defect should be treated from a young age.”
What can you do to reduce your cholesterol levels?
If you have a genetic disorder, you will need medication to keep your cholesterol levels under control. However, if there are no obvious genetic factors, lifestyle changes can still make a significant difference.
“Your doctor will start by assessing your risk,” says Maher. “They will check your blood pressure to make sure it’s not high, advise you to lose weight if you’re overweight, stop smoking if you’re a smoker, and increase your activity levels if you lead a sedentary life.”
Your doctor is also likely to suggest dietary changes. “Dietary changes can result in a 10% to 15% reduction in cholesterol,” says Maher.
“The first step is to cut down on saturated fat. This is the fat that’s hard at room temperature, such as the fat in meat, dairy products, and many processed foods. So you’ll have to minimise the fry-ups and take butter in moderation.”
Colleran advises switching to a Mediterranean diet. “It’s low in red meat, dairy products, saturated fats, and processed foods, and high in fresh fruit and vegetables, and fish, especially oily fish. It’s also high in wholegrain carbohydrates. It’s the ideal diet to lower cholesterol.”
Brown adds that it’s worth using healthier cooking methods, such as grilling or oven baking, instead of frying. “And eating foods that are high in plant stanols or sterols every day can help reduce LDL levels too,” she says. “These can be found in vegetable oils, nuts, seeds, legumes, fruit, vegetables, and wholegrains.”
What if this doesn’t reduce your cholesterol to the desired level?
If cholesterol levels remain high after trying lifestyle changes for several months, then doctors are likely to prescribe statins.
Maher explains that statins work by reducing the liver’s ability to produce cholesterol, which then prompts the liver to remove more cholesterol from the bloodstream. “This means there is less of it to deposit in our arteries,” he says.
Do statins have side effects?
There can be side effects, but they are not common, says Colleran.
“The one people complain of most is inflammation causing aches and pains in the muscles and joints,” she says. “If someone experiences this or any other side effect, we try them on another statin at a lower dose. If they get side effects from that, we try them on a third statin. It’s only when three different statins fail that we try an alternative medication.”
The reason doctors are keen to prescribe statins is due to the extensive research that has been conducted on them. Take a 2019 study published in The Lancet, for example. It looked at data from 187,000 people and found that statin therapy reduces major vascular events, such as heart attacks and strokes, in people of all ages.
Maher believes some people are under the misapprehension that statins aren’t safe.
“No drug is 100% safe,” he says. “We know that 10% of people taking statins get muscle aches for example. But statins have a bad rap. They reduce cholesterol significantly, leading to marked reductions in heart disease. If you’ve got high cholesterol and you can’t bring it down with lifestyle measures alone, your doctor is right to prescribe a statin.”
Are eggs bad for cholesterol?
Maher wants to debunk the myth about eggs. “Eggs may contain cholesterol, but our bodies only absorb a small amount of dietary cholesterol,” he says. “What’s far more important is the fat you consume. It’s the bacon you have with your eggs that you need to worry about.”
What else can we do to manage our heart health?
“The good news is that 80% of premature cardiovascular disease is preventable,” says Brown. “In addition to managing cholesterol, we can monitor and control blood pressure and blood sugar levels, stop smoking, and modify our diets. Physical activity is one of the greatest preventative tools, and we should all try for a minimum of 150 minutes of moderate intensity activity every week.”
It’s also critical to manage stress. “Stress can have a negative impact, making us more likely to drink, smoke, and eat unhealthily,” says Brown.
“This, coupled with the release of cortisol, which raises blood glucose and adrenaline, raises the heart rate and blood pressure and can increase cardiovascular risk. Exercise can help deal with stress, and so can staying connected to family and friends.”
Any final words?
“Everyone has cholesterol,” says Maher. “Higher levels of it are associated with an increased rate of heart disease, which is one of the leading causes of death in Ireland, killing some 9,000 people every year. We should all be aware of our cholesterol, check it regularly and take steps to control it if it becomes elevated.”
Irishexaminer.com