High cholesterol often has no symptoms, but it significantly increases the risk of heart disease and stroke. Photo / 123RF
High cholesterol often has no symptoms, but it significantly increases the risk of heart disease and stroke. Photo / 123RF
We all know that high cholesterol is not a good thing, but why is it unhealthy for you - and what’s the difference between “good” and “bad”?
If you have high cholesterol, you are not alone. A recent study from Our Future Health found 54% of us havehref="https://www.nzherald.co.nz/lifestyle/how-can-i-lower-my-cholesterol-do-supplements-work-how-about-psyllium-or-probiotics/64P6CJTHURCXTCO6WHTBWUJRKU/" target="_blank"> high total cholesterol levels. “The good news is that once you become aware of it, high cholesterol is preventable and treatable,” says Dr Dermot Neely, a former lipid specialist and trustee with Heart UK, the cholesterol charity. “Cholesterol is a type of blood fat that is made in the liver, found in some foods too. We all need some cholesterol in our bodies to keep us functioning, but having high cholesterol can clog up your arteries.”
What are the symptoms of high cholesterol?
High cholesterol is symptomless, which is a major concern because if left untreated, it can lead to heart attack and stroke,” says Ruth Goss, a senior cardiac nurse at the British Heart Foundation.
Overt symptoms of high cholesterol may manifest in people with familial hypercholesterolaemia (FH), a hereditary disorder in which the liver is unable to adequately handle cholesterol, where you may suffer from:
Tendon xanthoma - swellings made from cholesterol on the knuckles of your hands, your knees or the Achilles tendon at the back of your ankle.
Xanthelasma - small, yellow lumps of cholesterol near the inner corner of your eye and eyelids.
Corneal arcus - a pale white ring around the coloured part of your eye, the iris.
High cholesterol is often symptomless, making regular checks crucial. Photo / 123RF
Causes of high cholesterol
High cholesterol doesn’t have one cause but is affected by many factors, says Goss.
Your diet: Eating too much saturated fats - this reduces the liver’s ability to remove cholesterol, so it builds up in the blood.
Lack of exercise: Being physically inactive - being active raises the level of “good” cholesterol and reduces the level of “bad” cholesterol.
Smoking: Smoking can lead to high cholesterol levels and causes tar to build up in your arteries, making it easier for cholesterol to stick to your artery walls.
Age: You are also more likely to have high cholesterol as you get older, if you’re male and if you have a South Asian background, or if you have the genetic condition familial hypercholesterolemia (FH).
High cholesterol can be caused by factors like diet, lack of exercise, smoking, and age. Photo / 123RF
Other things that might increase your risk of high cholesterol
Kidney disease: When your kidneys aren’t working well, that also changes the way your body handles cholesterol.
Liver problems: The liver both produces cholesterol and clears it from the body, but if the liver isn’t working well the body struggles to do this.
Other considerations: Excess weight (especially around your middle), type two diabetes, underactive thyroid (hypothyroidism – when your body doesn’t make enough thyroid hormone) or growth hormone deficiency (when not enough of the growth hormone is made).
Kidney disease and liver problems can also increase the risk of high cholesterol. Photo / 123RF
Diagnosing high cholesterol
Ask your GP to check your cholesterol levels, which are measured using a simple blood test, sometimes referred to as a “lipid profile”. Your GP or practice nurse will take a blood sample to check for the following:
“If there is too much non-HDL in the blood, cholesterol can fur up the blood vessel walls, clogging them up - that’s why it’s called ‘bad cholesterol’,” says Neely.
HDL (high-density lipoprotein) cholesterol contains lots of protein and very little cholesterol. It carries cholesterol away from the cells and back to the liver, removing the cholesterol from the body in the process, which is why it’s called “good cholesterol”.
There is another kind of fat in our blood called triglycerides, which are found in fat cells. These can also make arteries shrink. Triglyceride amounts can be high if:
You are overweight.
You eat a lot of sugary and fatty foods.
You drink too much alcohol.
“Your GP should not make any decision on the results of a cholesterol test alone. You need to look at all the potential risk factors for heart disease at the same time. We have very sophisticated computer algorithms these days which look at body weight, height, cholesterol results, blood pressure, blood sugar and will give you a risk estimate for the next 10 years,” says Neely.
What is a healthy cholesterol level?
Heart UK recommends the following:
Total (serum) cholesterol: Below 5.0 mmol/L.
Non-HDL cholesterol: Below 4.0 mmol/L.
LDL cholesterol: Below 3.0 mmol/L.
HDL cholesterol: Above 1.0 mmol/L for a man above and 1.2 mmol/L for a woman (ideally around 1.4. Very high levels may not give extra protection).
Effects of high cholesterol on health
“High cholesterol can significantly increase the risk of several health conditions,” says Goss.
Elevated LDL cholesterol is a major risk factor for coronary artery disease and stroke.
High cholesterol levels in midlife are associated with an increased risk of dementia and Alzheimer’s disease later in life.
Studies also show high cholesterol can lead to peripheral artery disease (PAD). “PAD is often caused by a build-up of fats, cholesterol and other substances in and on the artery walls, a condition called atherosclerosis, which furs up your arteries with plaque. Plaque can cause arteries to narrow, blocking blood flow. In PAD, plaque collects in the arteries of the arms or legs,” says Neely.
Prevention and management strategies
There is a lot you can do to help lower your cholesterol.
Eat healthy foods and recipes that are good for your heart and cut down on saturated fats - the kind of fat found in butter, lard, ghee, fatty meats and cheese.
Get more active: Being active raises the level of “good” cholesterol and reduces the level of “bad” cholesterol.
Stop smoking: Smoking causes tar to build up in your arteries, making it easier for cholesterol to stick to your artery walls. If lifestyle changes are not enough to lower your high cholesterol, your doctor may prescribe statins. Around 7-8 million adults in the UK take them and they can reduce your LDL cholesterol by around 30%, sometimes even 50% with high doses.
Latest research and guidelines
Some people find it difficult to tolerate statins. New cholesterol-lowering medications called PCSK9 inhibitors lower non-HDL levels in high-risk patients. Researchers found when compared with placebos, cholesterol dropped 59% and cardiovascular events dropped 15%.
Dietary recommendations have also changed. A recent study suggests instead of trying to cut out cholesterol-rich foods such as butter, we should simply focus on healthy dietary patterns. For example, Mediterranean-style and Dietary Approaches to Stop Hypertension (Dash) diets that encourage us to eat fruits, vegetables, whole grains, low-fat or fat-free dairy products, lean protein sources, nuts, seeds and liquid vegetable oil.
A growing body of research suggests young people should be aware of their cholesterol levels earlier in order to take statins. Rather than attempting to undo damage, Neely recommends that statins could be offered at a younger age to keep arteries healthy.
Statins, prescribed widely, are linked to lower cardiovascular death rates in high-risk patients. Photo / 123RF
Considerations for high-risk groups
Certain people may require special consideration:
If you have diabetes, more aggressive cholesterol-lowering strategies are often recommended such as high-intensity statins like atorvastatin or rosuvastatin. These medications can reduce LDL cholesterol by 50% or more.
Ezetimibe can be added to statins in an approach referred to as “combination therapy” to further lower LDL cholesterol. It works by reducing the absorption of cholesterol in the intestines.
Cholesterol management should consider the impact on overall health and potential side effects of certain medications.
Genetic counselling and early intervention are crucial for those diagnosed with familial hypercholesterolaemia. FH is prompted by a gene change caused by a doubling of LDL-C levels from birth in otherwise healthy individuals, causing early heart attacks that can be entirely prevented if treatment is started at a young age, ideally by the age of 10. Testing should begin at 2 years for children with a history of FH in the family. All that’s needed is a straightforward blood test.
