The diagnosis can be worrying – but even slim, healthy people can have raised cholesterol. Here’s advice from a leading heart health expert
In a new column, we take a pressing health question and delve into the evidence with the help of leading experts.
More than half of people in the UK are thought to have raised levels of cholesterol. It can lead to inflammation and plaque building in the arteries, and in turn heart and circulatory disease – the cause of a quarter of deaths in the UK, according to the British Heart Foundation.
As there are no noticeable symptoms, it’s often only detected in check-ups, such as the NHS health check offered after the age of 40.
If your levels of total cholesterol are high – 5 mmol/L or higher – you’ll be offered lifestyle advice, or potentially statins, depending on your risk factor (calculated by your age, cholesterol reading, and other health conditions).
It can be concerning news, but cholesterol is more complex than you think, explains Dr Ali Khavandi, consultant interventional cardiologist at the Royal United Hospitals Foundation Trust at Bath.
The three causes of high cholesterol
People with high cholesterol can be split into three broad groups, he says. For one group, it’s down to their genetics, irrespective of their lifestyle. It affects about one in 250 people. “They may be thin, exercise regularly, but their cholesterol is very, very high. Often they will have family members that also have very high cholesterol and their diet is unlikely to make a significant contribution to lowering it.”
The second group, which Dr Khavandi notes is growing, will have high cholesterol alongside other metabolic symptoms: “these are patients, typically, that have too much visceral fat around their abdomen, and have associated conditions like pre-diabetes or type-two diabetes, high blood pressure, deranged cholesterol, obstructive sleep apnea, gout, and heart-rhythm disturbances called atrial fibrillation.”
Their high cholesterol, Dr Khavandi says, is a consequence of their diet and lifestyle. “If their diabetic control is very poor and their cholesterol is seven, then you would assume that there must be a significant metabolic contribution.”
But it’s also possible to have high cholesterol without an inherited tendency to it, or any other obvious lifestyle cause. This third group “are generally not significantly overweight and reasonably healthy although for many there can be opportunities to tweak.” As you age, your liver becomes less efficient at removing bad cholesterol. For women, the loss of oestrogen in menopause also can cause your cholesterol levels to rise.
How much you need to worry about cholesterol is in part determined by which of these groups you fall into.
For people with a genetic link, lifestyle changes will have little impact and so statins are required.
For people with metabolic causes, changes in diet and lifestyle can dramatically lower their levels and, if lifestyle doesn’t help then statins may also be recommended.
For everyone who is otherwise healthy but has raised cholesterol, there is a question over how much they should focus solely on their cholesterol levels. Some may need to make lifestyle changes, or may need medication, others may not. This depends on the other risk factors and whether lifestyle factors are something you can change. To get more clarity, you’d need to have your arteries analysed for inflammation – something that is not done by the NHS but can be done privately.
“Lifestyle changes are really, really important,” Dr Khavandi says, “but sometimes people get fixated on trying to lower their cholesterol through diet.”
How can I lower cholesterol – without statins?
If you want to try to lower it without going on medication, it’s worth remembering that eating foods that are high in cholesterol does not have an impact on your levels. So, contrary to what we once thought, foods like eggs (which are naturally high in cholesterol) won’t have an impact on your levels. In fact, many of the foods that are high in cholesterol are also very nutrient-dense (full-fat dairy, fish oil, shellfish, liver).
Instead, blood cholesterol levels are more influenced by saturated fats, trans fats, and refined carbohydrates as these can stimulate the liver to produce more LDL (low-density lipoprotein – also known as “bad” cholesterol).
Laura Wyness, registered nutritionist, explains that “we need some fats in the diet for energy, for absorbing fat soluble vitamins, for brain function and even for the immune system. But too much saturated fat in the diet, and any foods that are high in saturated fat, will raise your cholesterol.”
Nichola Ludlam-Raine, registered dietitian and author of How Not to Eat Ultraprocessed agrees: “While we don’t need to avoid all saturated fat, it’s wise to limit it — especially from processed meats, pastries, and fried foods — and instead prioritise unsaturated fats from sources like nuts, seeds, oily fish, and olive oil, which support heart health.”
Dr Khavandi says focusing solely on fat is misleading, even though products continue to emphasise this.
“I would certainly not advocate using special cholesterol-lowering supermarket margarines, yogurt drinks, or substituting your shopping for products that say ‘light’, ‘lighter’, ‘low fat’ or ‘low cal’,” he says. “These are generally low quality and highly processed products that will overall be bad for your health”.
Instead, he says it is also vital to look at sugar intake. A study by the Harvard School of Public Health found that drinking more than one can of sugary drink a day was linked to increased levels of unhealthy blood fats, including cholesterol, associated with a higher risk of cardiovascular disease.
Drinking alcohol and smoking are also known to affect your levels.
Addressing these issues can greatly improve cholesterol levels in many people, especially if they are in the metabolic group, he says. “When that metabolic group becomes insulin-sensitive again by cutting sugar, carbohydrates and alcohol in their diets, their visceral fat reduces and you see that the cholesterol typically improves profoundly.”
Exercise is also important – a review of the research in the journal of Heart and Circulatory Physiology shows regular physical exercise (such as following the NHS-recommended 150 minutes of cardio a week, plus two resistance training sessions) stimulates the body to move “bad” cholesterol to your liver so it can be removed from the body.
When to should I worry about cholesterol?
If your GP has told you that your cholesterol levels are too high, pay attention to their advice. But Dr Khavandi says that you should not worry unduly specifically about those cholesterol levels.
“The dietary opportunity is for metabolic patients. They can smash their cholesterol and reverse the underlying illness (root cause) by improving their diet and weight management: specifically, the consumption of excess sugar, refined starchy carbohydrates and alcohol if appropriate,” he said.
For the majority, the focus should be on general measures of health – managing weight and eating a wholefood diet that avoids processed foods. Increasing soluble fibres like oats, beans, lentils and fruits can also lower LDL cholesterol naturally with the added benefit of increasing fibre.
“If you think you are doing all these things and don’t have a strong family history,” Dr Khavandi says, “you probably don’t need to worry too much about your cholesterol if it’s ‘slightly high’.”