Some say cholesterol lowering drugs do more harm than good: real or rumour?

Statins, the famous cholesterol lowering drug, continues to fuel controversy. This medication - which is taken to prevent heart attacks and strokes - is among the most widely prescribed medication in the United States. But some experts, writing for the British Medical Journal, say it can do more harm than good. And others believe it causes problems in the bedroom.

Associate Professor Dirk Blom, who’s the division head of Lipidology at the University of Cape Town and Head of the Lipid Clinic at Groote Schuur Hospital gives the facts. Professor Blom’s personal research interests include genetic disorders of lipoprotein metabolism. He has published in multiple peer-reviewed journals including The Lancet, the New England Journal of Medicine and the Journal of Clinical Lipidology.  

What is cholesterol? Cholesterol is a soft fatty molecule made by all animals. It is a member of the sterol family. Although plants also produce sterols, they cannot make cholesterol. Cholesterol plays an important role in cell membranes and many hormones, so-called sterol hormones, are made from cholesterol. 

Why are high levels of cholesterol dangerous? Cholesterol and other fats are transported from the liver to the rest of the body in the bloodstream by transport proteins called lipoproteins. This often causes problems. Too much cholesterol which is transported from A to B could be dangerous if it is spilt along the way. The easiest way to explain it is probably to think of sand that must be moved from one point to another. Say for instance one moves ten bags of sand from A to B in various vehicles. These vehicles come in different shapes and sizes. One, a dilapidated bakkie (or a low density lipoprotein), carries the sand (cholesterol) but crashes and drops it all over. A second vehicle(refuse removal truck or high-density lipoprotein) , then removes the dropped sand. So, although both vehicles carry sand it is dangerous if one has 10 dilapidated bakkies and only one refuse removal truck. The number of bakkies and refuse removal trucks needs to be in balance. When people refer to good or bad cholesterol levels, they are actually referring to how much cholesterol is carried in each type of vehicle. To be healthy one wants less low-density lipoprotein cholesterol (sand carried in a bakkie) and more high-density lipoprotein cholesterol (sand carried in a municipal refuse removal truck). 

When is cholesterol too high? It all depends. Most inhabitants of the Western world probably have higher cholesterol than would be ideal, especially when considering the cholesterol levels found in populations untouched by Western civilisation. In an individual assessing whether the cholesterol level is too high requires a more detailed evaluation starting off by checking HDL and LDL cholesterol levels. As a rough guide, it is generally desirable to have a total cholesterol count of under 5. The next step is then to look at the presence or absence of other risk factors (for example smoking, high blood pressure, diabetes) and then decide whether intervention is required.  Always remember that the reason for lowering cholesterol is to reduce the risk of heart attack or stroke and not to simply bring down the numbers. From this it follows that the person with the highest risk of stroke or heart attack gains the most from treatment to lower cholesterol. If the risk of having a heart attack or stroke in the next 10 years is 1%, treatment would still be effective but may not be worth the effort as one would only decrease the risk 1% to 0.5 % for argument sake. In another individual with a 10-year risk of 20% treatment could halve the risk to 10%. 

Does high cholesterol cause heart attacks? Yes, it is a causal risk factor which means that having high LDL cholesterol increases one’s risk of a heart attack, but not everyone who has high cholesterol will have a heart attack and not everyone who has a heart attack has high cholesterol. The role played by cholesterol varies in importance from patient to patient . If we have a patient with an inherited high cholesterol that is massively elevated, say about 12, then a heart attack will almost always be exclusively mediated by the cholesterol. The cholesterol will be the big bad guy in the room. If someone has a cholesterol of 5.5 but also smokes, doesn’t exercise, has high blood pressure and eats badly then cholesterol will be a contributing factor and not necessarily the dominant factor.  

Will a high FAT diet increase one’s cholesterol? This is obviously a contested topic. What has been proven scientifically is that the LDL cholesterol levels of a group of people rose after they were given a diet high in saturated fat over a fixed period. There is little dispute about that. How much it will rise is variable. There seems to be quite a variability in dietary responsiveness. In some people there are more changes than in others. 

How much fat can one eat? Again, the answer varies. Some populations whose original diets or primordial diets are rich in carbohydrates, can stay healthy and lean as long as they stick to unprocessed and complex carbohydrates and remain active. In comparison other populations, such as the Inuit, can stay healthy and lean despite mainly eating foods high in saturated fat. So, the human body can cope with varying fat intakes. In the past one was told all fat is bad and one must avoid it at all costs. Today we accept that this is wrong. What is crucial is what one replaces the high fat diet with when changing to a low-fat one. If it’s white bread or coke, one will be worse off. Replacing it with poly unsaturated fat or unrefined grains etc. is a much better option. The fat debate is probably more complex than one thinks. What experts agree on is that highly processed foods are unhealthy. If one can’t recognise where something comes from or if it doesn’t resemble the chicken or vegetable in its natural state it is probably not good. Rather than bash one another’s heads about how much fat is good, we should focus on getting more fruit and vegetables and less processed foods. My reservation about the Banting diet, which proposes an extremely low carbohydrate and very high fat intake, is that there is no reliable data of populations which have eaten such extreme low carb diets over a lengthy period. If one goes full Banting and eats less than 20g of carbohydrates per day, one is in unchartered territory. Doing this is extreme and problems may arise at some point. The Banting lifestyle is also problematic from an ecological point of view. If everyone eats meat products mainly and other high-fat products, where do we get enough butter and cheeses for everyone? To produce one kilogram of butter one needs more resources than to produce an equivalent amount of fruit and veg. So, one also has to think of the planet. 

Is Salmon fish which is high in fat, a healthy alternative to red meat? Salmon fish and most fish types contain mainly polyunsaturated fat and dietary guidelines recommend a regular intake of fish.

How do South Africa’s cholesterol figures compare to the rest of the world? We have a higher frequency of inherited or genetic hypercholesterolemia. The white Afrikaans population and some Indian communities have a higher frequency of inherited high cholesterol. Cholesterol levels in the South African white population without inherited high cholesterol are similar to those seen in Western Europe and the Americas. In African populations cholesterol is increasing rapidly as a result of urbanisation and changing lifestyles.

Does one’s gender or age affect one’s cholesterol levels? Cholesterol tends to rise in females after menopause. Pre-menopausal men usually have higher cholesterol than females. Although one’s diet can influence cholesterol levels, genetics or choosing your parents well, does play an important role. 

There are many different opinions on whether the side effects of medication outweigh the benefits? There is no law forcing anybody to take medication but what one needs to do is to chat to one’s GP and make an informed decision. If one’s risk is high the need to take medication is stronger than when it’s low. 

How accurate are reports that it lowers one’s libido? The effects on libido doesn’t show up in double blind randomised controlled trials. Such a trial involves giving one group of men the real medication and another a placebo, you get the same number of reports of erectile dysfunction. So it’s not higher in the group on the medication. Erectile dysfunction is often related to the reasons why a doctor prescribes the drug. Someone who has had a heart attack or who has diabetes and high blood pressure, usually also has clogged arteries. In such cases the vessels that take blood to the penis are not in great shape either. A doctor may then prescribe cholesterol lowering medication. If things in the bedroom are not as good as they should be after three months, then the cholesterol tablet is blamed when in fact it’s the blood vessels that aren’t functioning properly. One always has to be careful of what is called reverse causality, where one thing is identified as the cause, when in fact it’s something else. 

Are Are there natural substitutes? Using an analogy between a car and a statin. If one has a car, one would generally wear a SABS approved safety belt rather than a home-made one. There are natural products that do lower cholesterol, for instance a Chinese product called red yeast rice that does contain some statin. The effect is variable and one is not sure how much of the active ingredient it contains. Generally, the natural products are not powerful enough. I advise patients to go for products that have passed quality control and strict regulation. 

Finally, are genetics the most important factor that determine one’s cholesterol levels? Yes, it is largely genetic, but that doesn’t mean one should give up on a healthy lifestyle because there are many other health benefits that go along with a healthy lifestyle besides the numbers.

 Has medication made it possible for those born with a predisposition to high cholesterol to have normal life expectancy? Yes, the availability of cholesterol lowering medication has been a revolution for large numbers of people who have a severe cholesterol problem. If one looks at UK data of the sixties before the medication was available these patients died at the age of 42. Now with early treatment they can have normal life expectancy. It has really made a massive impact .