Cholesterol – harmful or beneficial? How can nutrition and lifestyle support good cardiovascular health?
The impact of cholesterol is a controversial topic in the world of medicine. Earlier this month I had a number of questions from clients about whether or not they should consider a statin and join the eight million other people in the UK who take them.
I have read a number of papers on cholesterol over the years, often conflicting in nature, which means that today at least, there is not a clear cut answer. I’m a nutritionist who supports pharmaceuticals only where they are necessary and life changing, but generally my approach is to first adopt preventative strategies based on nutrition and lifestyle, as my aim is to help people lead healthier lives. However the topic of cholesterol transportation in the body is pretty complicated – we need cholesterol to build cell walls, make hormones, help make vitamin D, produce bile acids and more. And then there is the research that hypothesises that people with high cholesterol live longer. Who is right?
Widespread statin therapy is financially beneficial for the NHS as the cost of providing statins to a large population is relatively small, but so are the protective effects. This is called the ‘number needed to treat’ which is currently 4. What that means is that if 1000 people with a 10% chance of heart attack or stroke within a decade are put on statins, around four cases may be prevented. Good news for the 4 who needed it, but there are 996 who possibly didn’t need it.
A very brief science overview (skip this part if you just want to know what to do!)
Always ask for a copy of your blood work and always talk your results through with your doctor so you have an opportunity to ask questions. They will read them in conjunction with your own QRISK3 score. The QRISK3 algorithm calculates a person's risk of developing a heart attack or stroke over the next 10 years.
Whilst this is normally done by the doctor, there is no reason why you can’t do it yourself online.
Next, your HDL/triglyceride ratio is an important calculation and the one I look at closely in clinic.
HDL (high-density lipoprotein) cholesterol, sometimes called “good” cholesterol, absorbs cholesterol in the blood and carries it back to the liver. Triglycerides are a type of fat (lipid) found in your blood. When you eat, your body converts any calories it doesn't need to use right away into triglycerides.
To calculate your own HDL/triglyceride ratio, simply divide triglycerides by HDL. The closer you are to 1, the better. Under 2 likely puts you at low risk for heart disease. Anything over 3 needs attention because as triglycerides go up, fat and sugar is stored in the liver, making it difficult for the liver to produce HDL.
LDL (low-density lipoprotein) cholesterol, sometimes called “bad” cholesterol, makes up most of your body's cholesterol and a higher than normal reading theoretically raises your risk for heart attack and stroke.
Whilst eating certain types of fats does raise LDL (not all fats are bad!), it may depend on the size and density of the LDL particles and without a specialist particle size test, it is hard to know what the impact of LDL is having on your arteries. The alternative is more sophisticated screening. Whilst in the US the most common test you may have heard about is a calcium score test, these days in the UK, your cardiologist may have access to more up to date screening such as a cardiac CT scan.
Other measures. There is a growing body of research that ApoB (apoliproprotein B) - a protein that helps carry fat and cholesterol through your body, may be a much better predictor of heart disease risk than LDL alone. Then there is also the matter of homocysteine levels – a high level being a known risk factor for heart disease, dementia and stroke. Homocysteine is an amino acid. Vitamins B12, B6 and folate break down homocysteine to create other chemicals your body needs. This means that homocysteine can be managed through nutrition.
Where there is a hereditary risk factor for heart disease, elevated Lp(a) is something to check and look out for. It is often seen in people who have out of the blue heart attacks. Lp(a) is a member of the apoB family, but due to it’s structure it is more likely than a regular LDL particle to get stuck in the artery wall.
APOE (apoliproprotein E), is a protein that plays an important role in transporting lipids and cholesterol in the bloodstream, especially the brain. However the variant has a large influence on how lipids are metabolised. The APOE gene has three common variants, (alleles): e2, e3 and e4. The e2 allelle has been found to be protective against certain diseases, particularly cardiovascular and Alzheimer’s. Studies have shown that individuals who inherit two copies of the e2 allelle have a lower risk of developing cardiovascular issues compared to individuals with the e3 or e4 genotypes. Even one copy of e2 (and no e4), carry about a 30% chance of being more likely to achieve extreme old age - that’s late 90’s. Researchers have identified other cholesterol related genes - CETP and APOC3. APOE e2 is not to be confused with APOE e4 which appears to multiply one’s risk of developing Alzheimer’s.
Diet and Lifestyle as a preventative strategy
Regardless of whether you choose statin therapy, in my experience, you can make a sizeable change in ‘abnormal’ cholesterol readings within three to six months with a little self help and dedication:
Movement. Consistent exercise can really move the needle on cholesterol numbers. Increasing the length of the daily walk and walking more briskly is often enough. Put some effort into it so you become a little breathless each day.
Weight loss. Whilst it is true that slim people may also have cholesterol numbers that cause concern, if you are overweight, chances are that you can materially influence your data without having to resort to statin therapy if you shed some kilos. You will also reduce your diabetes and stroke risk too.
Nutrition. One misconception about ‘abnormal’ cholesterol is that saturated fat is to blame. This is not totally the case, it’s primarily sugar and high GI carbs. Reduce sugar and your triglyceride numbers go down, thus reducing your risk level. Too many carbs and alcohol raise triglycerides. It is true that if you follow a strict ketogenic diet, it can temporarily raise both HDL and LDL cholesterol, but there is no evidence that this may be harmful.
Choose foods which may be supportive of ‘good’ cholesterol function, eg dark leafy green vegetables, cruciferous vegetables, oats, green tea, ginger, beetroot, dark chocolate, oily fish (omega 3), olive oil and olives, avocado. Stick to low sugar fruits such as berries and apples. No juices. Purple foods (for the polyphenols), are your friends. Avoid inflammatory fats, eg sunflower or ‘vegetable’ oils which are high in omega 6 and highly processed. Try to eat a diet which contains minimally processed foods.
Supplementation. There are certain vitamins, minerals and probiotics that may support the management of cholesterol as well as support nutrient deficiencies which may have been created by statin therapy. These are very individual in nature and require personalised support depending upon health goals, medical conditions and pharmaceutical contraindications.
Don’t be afraid to ask your GP detailed questions about your data and your risk level.