It’s been Cholesterol Awareness Month throughout October, and after having a number of conversations with clients about cholesterol I thought I’d do a blog post about it for everyone to read.
What is cholesterol?
Cholesterol is a fatty substance found in the blood which plays a vital role in the proper functioning of our cells. It is produced naturally in the liver and everyone has cholesterol – in fact we all need cholesterol to stay healthy and to maintain the structural integrity and fluidity of our cell membranes (amongst many other things).
Having too much cholesterol however can clog up our arteries and lead to health problems in the future with an increased risk of heart attack, stroke and vascular dementia. Like any other fat cholesterol can also be damaged by oxidation.
Cholesterol is found in some foods, with all animal-based foods containing cholesterol in varying amount.
There is a link between saturated fat intake and cholesterol levels but most of the circulating level of cholesterol in the blood is of endogenous origin (ie produced by the liver rather than dietary intake) via a complex 37-step process. The biosynthesis of cholesterol is directly regulated by the cholesterol levels present, with our body able to increase or decrease the production of it.
Different types of cholesterol
Cholesterol is a blood fat, and as it cannot circulate loosely in the blood it is carried around our body by proteins in the blood. When cholesterol and proteins combine they form lipoproteins, and there are two main types – one which is “good” for our health whilst the other one is “bad” (this is where the confusion of cholesterol being bad for us arises from):
- Non-HDL (Non-High Density Lipoproteins): these take cholesterol from the liver to the cells that need it. Too much creates a build up of fatty deposits (atheroma) which narrows the arteries. This makes it harder for blood to flow through, therefore limiting the circulation of blood and oxygen and leading to an increased risk of heart attack or stroke – this is why this is referred to as the “bad cholesterol”.
- HDL (High-Density Lipoproteins): these remove excess cholesterol from the cells and return it to the liver, where it is broken down and removed from the body – this is the “good cholesterol”.
Ideally we need a low level of Non-HDL, and a high level of HDL, allowing the “good” lipoproteins to get rid of and help excrete the “bad” ones!
You may have heard “bad” cholesterol being called “LDL” (Low-Density Lipoproteins) cholesterol – this used to be the main measure of “bad” cholesterol but it has been established that other forms of non-HDL cholesterol are also harmful, hence referring to it as non-HDL rather than LDL cholesterol these days. Chylomicrons or ultra-low-density lipoproteins (ULDL), very-low-density lipoprotein (VLDL) and intermediate-density lipoprotein (IDL) are furthertypes of lipoproteins in the blood.
Functions & benefits
We all need cholesterol for many functions in the body and to stay healthy, it’s only when it gets too high that it can be a problem for our health.
Cholesterol is also a precursor molecule for a number of hormones.
We need cholesterol for a number of things including:
- the proper functioning of our cells – cholesterol maintains membrane structural integrity and fluidity
- the synthesis of hormones – including the adrenal gland hormones cortisol and aldosterone, and the sex hormones progesterone, oestrogen and testosterone
- the production of bile acids, which are derivatives of cholesterol synthesised by liver cells, making it essential for the digestion of fats
- the production of vitamin D – cholesterol is needed in our skin cells as a first step to make vitamin D from sunlight
High cholesterol
High cholesterol is very common, but a lot of people don’t know they have it because they don’t usually experience any symptoms.
Too much non-HDL cholesterol in the blood can lead to heart and circulatory diseases if it is not managed, as explained above.
High cholesterol can be caused by lifestyle but it can also be inherited, and typically people don’t know they have it or are aware it could apply to them – especially when they are young, slim and otherwise healthy!
The only way to establish your cholesterol level is to get a cholesterol test. It’s also worth asking your GP for the exact cholesterol levels – some people are told that their cholesterol levels are “fine” when in fact they are right on the borderline. (NOTE: This applies to all test results, including blood tests!)
You might also see a triglyceride level on your cholesterol test results, and your GP can advise if these are too high too – triglycerides are a type of fat stored in the body’s fat cells. High triglyceride levels can be due to being very overweight, eating a lot of fatty and sugary foods or drinking too much alcohol, and this can also contribute to the narrowing of the artery walls. You can have a normal level of HDL and non-HDL cholesterol but still have a high triglyceride level, so this is worth monitoring.
Without going into details about medication for cholesterol I just want to make one important point about statins, which is the current main medical treatment. Statins do block the enzyme that makes cholesterol, but it’s that same enzyme that also makes Co-enzyme Q10 (CoQ10) which is vital for the health and functioning of the heart. More info on CoQ10 in a future blog post!
Risk factors for high cholesterol
As mentioned above anyone can have high cholesterol levels, no matter what the age, weight or fitness levels, and this can be inherited.
There are however some additional risk factors that play a big role in having high cholesterol levels:
- Genes & family history – some people are born with familial hypercholesterolaemia (FH), a genetic condition where the liver is unable to remove excess LDL cholesterol, resulting in exceptionally high levels of cholesterol in the blood
- Smoking – this is a big risk factor. The build-up of tar caused by smoking in the arteries makes it easier for cholesterol to stick to the artery walls, resulting in a build up of fatty deposits which affects the circulation of blood and oxygen. Cigarette smoking also increases the oxidation of fats, and damaged cholesterol becomes more difficult to clear.
- Eating a lot of foods high in saturated fats
- Being overweight
- Lack of exercise / movement & sedentary lifestyle
- An underactive thyroid gland
- Ethnic backgrounds – research shows that people from South Asians, Africas and African Caribbeans in the UK have an increased risk of developing heart and circulatory diseases than white Europeans
Managing high cholesterol levels
There are lots of things we can do to manage our cholesterol levels, and high cholesterol levels can be addressed by making some positive lifestyle and dietary changes.
All animal foods contain cholesterol, with major dietary sources including cheese, egg yolks, beef, pork, poultry and fish, but that doesn’t mean that we should cut all these foods out. Human breast milk also contains significant quantities of cholesterol. Not all foods that are high in cholesterol are automatically high in saturated fats though.
In the past the general advice was to eat a low-fat diet, but this has evolved as we realise the importance of the “good” fats for our health and wellbeing, especially essential fatty acids like omega-3. I did a separate blog about why essential fatty acids are so good for us a while ago which is worth reading in relation to this.
There are a number of nutritional approaches to support healthy cholesterol levels and metabolism.
5 top tips for cholesterol management include:
1. Consume sufficient dietary fibre. This helps ensure regular bowel movements and the elimination of excess cholesterol from the bowel. Fibre food sources include whole grains, whole vegetables & fruit, legumes & beans, nuts & seeds. Further details about fibre and some tips for increasing your fibre intake are here on my blog.
2. Reduce saturated fats in your diet – this is the type of fat that raises blood cholesterol with food sources including cakes, biscuits, milk and white chocolate, pastries, pies, fatty meats, processed meats like sausages, burgers and bacon, palm oil, butter, margarine, cream, cheese. Also avoid foods containing trans fats, which are particularly found in processed foods.
3. Incorporate healthy fats into your diet, including omega-3 (nuts, seeds, olive oil, oily fish). These have a positive effect on cholesterol levels and contribute to by raised HDL and lowered LDL levels.
4. Reduce foods high in sugar and starchy carbohydrates – these alter blood fat profiles by stimulating the production of insulin, which in turn increases the liver’s production of triglycerides and cholesterol. Research has found that diets high insugar raise make LDL and triglycerides levels whilst lowering the “good” HDL cholesterol.
5. Consume plenty of vegetables in a variety of colours (and a couple of portions of fruit) – vegetables always get a shout out, no matter which health condition! When talking about cholesterol specifically, the antioxidants in the vegetables protect the cholesterol from being oxidised and causing damage.
I also want to mention garlic and green tea in relation to cholesterol (and because I love both of these!). Garlic has been shown to have cholesterol-lowering effects, and its antioxidant properties may protect cholesterol from oxidation (oxidised cholesterol is the most damaging, hence also the importance of the antioxidants in the vegetables). Green tea also has antioxidant properties, and it has been found to contain cholesterol-lowering compounds.
When it comes to lifestyle, stress management is an important factor to address as chronic stress increases demand for steroid hormones, meaning the liver needs to produce more cholesterol to meet that demand – which results in higher cholesterol levels in the blood. Smoking can be another huge contributing factor to cholesterol build up in the arteries as explained above.
High cholesterol can be caused by many different things, not all of which we can control – but taking care of the things we CAN control certainly helps lower the risk.
—————————
Remember that a healthy, balanced and nutrient-dense diet low in saturated fats is key (and to “eat the rainbow”!) for general health, and that nutrition and lifestyle can make a huge difference to both your physical and mental wellbeing.
As always, if you have any questions or comments regarding this post then please feel free to get in touch or check out my 1:1 consultation package if you interested in a personalised programme.
Thank you for reading and keep well x
