Watching your diet is one of the most important ways to keep your blood cholesterol levels in check. Find out which foods you should eat more of, and which to avoid to help prevent or manage hyperlipidemia.
What is Cholesterol?
Cholesterol is a fatty substance found in the bodies of animals, including humans. It is essential for life and is found in every cell. Cholesterol helps keep every cell healthy, creates vitamin D and some hormones, and is even used to make the chemicals we need to digest our food properly.
As blood is water-based, fatty substances like cholesterol do not travel in them well, so cholesterol and certain proteins come together into tiny packages of protein and fats called lipoproteins. These lipoproteins are able to pass through the bloodstream and get to the parts of the body where they are needed.
While most of the cholesterol in our bodies is produced in the liver, some also come from our diet.
Although cholesterol is essential, there is more than one type of cholesterol – broadly speaking, there is ‘good’ cholesterol and ‘bad’ cholesterol, and many people have too much of the ‘bad’ kind.
‘Good’ and ‘Bad’ Cholesterol
As mentioned earlier, cholesterol travels through our bloodstream via proteins called lipoproteins. There are 2 types of lipoproteins that carry cholesterol throughout our body: low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL).
LDL cholesterol carries cholesterol to the tissues of the body, and HDL returns excess cholesterol to the liver to be filtered and recycled or removed from the body.
Having too much LDL means that there is more cholesterol in the bloodstream than the body needs. This unused cholesterol can form deposits on the walls of our blood vessels and other areas of the body. High levels of LDL cholesterol increase a person’s risk of cardiovascular diseases. This is why LDL is often referred to as the ‘bad’ cholesterol.
On the flip side, having high levels of HDL cholesterol means that the body is better at removing LDL cholesterol from the blood. In essence, the ‘good’ HDL cholesterol effectively cleans up any spare ‘bad’ LDL cholesterol and returns it to the liver to be broken down.
Why Does it Matter if I Have High Cholesterol?
When there is too much LDL or ‘bad’ cholesterol circulating in the blood, it begins to collect on the insides of the walls of our blood vessels. Having a fatty build-up or fatty plaque inside a blood vessel can reduce the blood flow through the vessel, which causes problems with circulation.
When the blood flow through a vessel is reduced, the blood cannot carry enough vital nutrients like oxygen around the body and those hard-to-reach parts can become damaged. If the part of the body experiencing reduced blood flow is a critical organ, it can cause serious problems. Reduced blood flow to the heart muscle is a heart attack; reduced blood flow to the brain can cause a stroke.
Cardiovascular disease – conditions affecting the heart and circulation – are responsible for around one-third of all deaths in Singapore, and having high cholesterol is a major contributing factor. The only way to know you have high cholesterol is to go for a blood test, which can be arranged as part of a regular general health check-up. People are at higher risk of cardiovascular disease as they get older, so attending routine health checks becomes more important.
What Raises Cholesterol?
There are three main reasons why someone might have high cholesterol:
This is a condition where someone has a genetic predisposition to develop high cholesterol. It runs in families, and can make it more difficult – but not impossible – to control blood cholesterol just by lifestyle changes – although following a healthy lifestyle still contributes to an overall lower risk of many serious diseases.
The more active we are, the better we are at using our bodies’ resources. Being overweight and inactive both increase LDL cholesterol and lower HDL cholesterol.
Certain fats in our diet can have a major impact on our LDL cholesterol levels. Watching our diet can also improve cholesterol levels by helping us gain or maintain a healthy weight. Some foods and drinks are actually beneficial and can have a significant positive influence on blood cholesterol levels.
High Cholesterol Foods to Avoid
Knowing which foods have a negative effect on good and bad cholesterol levels can help us make healthy choices for our own and our families’ diets. Foods to watch out for include:
1. Dietary Cholesterol
Only animals make cholesterol, so people who eat an entirely plant-based diet do not consume any cholesterol. However, it’s not just as simple as avoiding animal products altogether.
Our bodies make our own cholesterol, and a plant-based diet that is high in saturated fat and low in nutritious foods can still give us elevated blood cholesterol levels. There are also some animal products that can be an important part of a healthy diet and can help to reduce overall blood cholesterol levels.
2. Saturated Fat
Saturated fats are usually fats that are solid at room temperature, like butter, cream, and the fat in fatty meat. There are a few vegetable sources of saturated fat too, such as coconut oil and cream.
3. Trans Fats
Trans fats are the kind of fat found in heavily processed foods. Hydrogenated vegetable oil is a vegetable oil that has been treated to make them act more like saturated fats. This makes them a useful and inexpensive ingredient for food manufacturers looking to add a creamy texture and rich flavour to processed foods.
However, trans fats have a serious negative impact on health. Besides being high in calories, trans fats are almost devoid of any nutritional value and cause high LDL cholesterol and low HDL cholesterol.
Sugary foods are high in calories and low in nutrients, contributing to an unhealthy diet and being overweight. Having a high sugar diet increases cholesterol levels in two ways: firstly, it increases our body fat and secondly, has a direct effect on the lipid (fat) profile of our blood.
Sugar has no real value beyond simple calories and comes with significant health drawbacks. Not all sugars are equal, however. While fruits may be high in natural sugars, it generally has a better overall effect on the body, blood lipids and blood sugar spikes as compared to the same amount of sugars in a simpler form, like those found in soft drinks. This is because fruits contain healthy amounts of fibre, which reduces the speed at which sugar is absorbed by the body. Furthermore, fruits are rich in a range of other nutrients, which is beneficial for overall health.
Can I still eat eggs?
Eggs are high in dietary cholesterol. However, they are also packed with protein and other essential nutrients, and the cholesterol they contain does not appear to raise blood cholesterol levels as much as it might be expected to. Studies into whether or not eggs have a specific negative effect on cholesterol levels have to account for the way people commonly cook and eat eggs – alongside lots of fried and fatty foods. Eggs can certainly be incorporated into a healthy diet, but can also be a feature of many unhealthy diets.
9 Foods that Help Reduce Blood Cholesterol Levels
Reducing the harmful fats and empty calories in your diet is a great start when you are trying to improve your cholesterol levels and overall health. However, there are also lots of good foods you can focus on as part of a healthy diet and lifestyle. There are even some foods that can directly improve your cholesterol.
1. Oats and Barley
These two grains are particularly high in a substance called beta-glucan. Beta-glucan is a form of dietary fibre that actively reduces LDL cholesterol levels, and also has a positive effect on obesity and metabolism.
2. Vegetable Oils
Mono- and poly-unsaturated fats can have a positive effect on cholesterol and cardiovascular health. Rich sources of good fats include avocados, nuts, seeds, olives, and healthy vegetable oils like olive or flaxseed oil. Fat is essential in the diet, and switching unhealthy fat for these healthier options can improve cholesterol and overall health. However, it is still important to watch your overall fat intake, especially if you are overweight.
Different types of nuts contain different nutrients and healthy fats, including the heart-healthy omega fatty acids. Eating different types of nuts will add a wide range of nutrients to your diet. Nuts are also a rich source of protein and contain lots of healthy fibre.
4. Oily Fish
Oily fish like sardines and mackerel are well-known for their heart-healthy properties. The reason they are so good for the cardiovascular system is the high levels of healthy fats, in particular omega 3 fatty acid, which improves cholesterol levels and cardiovascular risk. Fish is also a good source of protein.
Eating a wide range of vegetables is good for your cholesterol levels, heart health, and all-round wellbeing. The healthy impact of a diet with lots of fresh, frozen, tinned or dried plant produce cannot be overstated, and the benefits are as varied as the vegetables themselves.
Vegetables are full of fibre which is essential for healthy cholesterol levels. Complex carbohydrates improve our metabolism, the way we digest food and use energy, the way we store and use the fat in our body, and our blood sugar and cholesterol levels. Eating a variety of vegetables means you’ll easily get a wide range of essential nutrients in your diet.
Adding more fruit to your diet, or even better, swapping a high fat pudding for a piece of fruit or a fruit salad, has a huge range of beneficial effects on your health.
Some fruits are particularly high in pectin – the substance that makes fruit jams (jellies) set – which has been shown to reduce cholesterol levels. Some fruit pectins have stronger cholesterol-lowering properties than others, however, and apples and citrus fruits are particularly good.
Different fruits have different levels of vitamins and minerals, and other nutrients, so eating a wide range is recommended for good health. A recent study found that blueberries do raise levels of ‘good’ HDL cholesterol even though they have little direct impact on LDL cholesterol.
7. Low-fat Dairy
Dairy products like milk and yoghurt are a good source of protein, calcium, and other vitamins and minerals. Some dairy products can be high in saturated fat, however, so low-fat options are a good choice.
8. Dairy Alternatives
Dairy alternatives are often based on plant milks made from oats, soy, nuts or rice. Some of these products in themselves can have a slight positive impact on LDL cholesterol levels. However, soy milks, soy yoghurts and other alternatives can have an even greater impact when used as a replacement for dairy products, offering a cholesterol-free option for those looking to reduce their cholesterol intake without missing out on taste. Choosing fortified products with added vitamins and minerals can help add to a healthy diet.
9. Plant Sterols and Stanols
Plants produce substances called sterols which act to block excess cholesterol absorption in the body. Eating a diet which is rich in fruit and vegetables means that we have a natural intake of these substances, but there are also some products specifically designed to get high levels of plant sterols and stanols into our diet. These are usually in the form of low-fat dairy products which are advertised as cholesterol-lowering foods.
A Diet for High Cholesterol
When planning a diet to improve heart health and cholesterol levels, it is important to focus on food that you should eat more of and know the foods are likely to be harmful.
It is also crucial that any dietary changes you are making are practical and practicable. For example, some may find it easier or have more time to cook fresh meals than others. However, a diet rich in fruit, vegetables, nuts and seeds, legumes, wholegrain carbohydrates and lean proteins can be cheap and easy for anyone to achieve.
Making sudden big changes in your diet can be difficult for anyone, and suddenly starting a diet that you find restrictive or unpleasant can feel almost like a punishment and impossible to stick to. Every little healthy change can help, and some people find it easiest to start small by swapping unhealthy food for a healthy alternative. For example, you may decide to swap fatty meat for lean meat, try using olive oil instead of butter, have a handful of nuts instead of a bag of chips. Having an idea of your regular diet and a few ways to improve it can help the next time you go grocery shopping. Make a few healthy changes and see how you feel.
If you are serious about changing your diet to a heart-healthy, cholesterol-improving one, try keeping a diary of the meals and snacks you eat over a period of time and then see where you can make the changes. Identify high-fat foods and think about better alternatives. You may be surprised to find out how much healthier your diet can be!
Other Ways to Reduce Cholesterol
Having a healthy diet can have a fantastic impact on your blood cholesterol levels, but it works best if you also follow a healthy lifestyle in other ways. Being more active and maintaining a healthy weight are also essential ways to stay heart-healthy.
Smoking also raises LDL cholesterol and lowers HDL cholesterol. Chemicals in cigarette smoke affect the composition of lipids in our bodies, as well as the way our body uses and reacts to those lipid particles. Stopping smoking directly reduces LDL cholesterol levels and raises HDL cholesterol levels, and is, for a huge number of reasons, one of the most important things you can do to improve your health.
A high alcohol intake can also cause levels of bad cholesterol to rise. Excessive alcohol intake also damages the liver, which is the organ we rely on for regulating our cholesterol levels. Drinking alcohol is also commonly linked to making unhealthy choices in our diet.
Although there is a lot we can do to improve our cholesterol levels and cardiovascular risk, there are some limitations. Some people are just more prone to high cholesterol due to their genetic makeup. People who are at particularly high risk should work closely with their doctor to have their levels monitored more frequently and may be prescribed medications to take alongside healthy lifestyle changes.
If you are concerned about your risk of hypercholesterolaemia or related conditions, a GP can help you understand what your risks are and what you can do about them.
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