Managing High Cholesterol and Type 2 Diabetes Together

Written by Madeline Blackburn

In 2023, 4.4 million people in the UK were living with diabetes, with another estimated 1.2 million people yet to be diagnosed. Approximately 90% of these cases were type 2 diabetes (1). Diabetes costs the NHS around £10 billion per year (1). 

As of 2023, health research project ‘Our Future Health’ found that in volunteers tested at that stage, which was around a quarter of a million people, 54% had high cholesterol (2). For many, this may be genetic, with familial hypercholesterolaemia affecting approximately 1 in 250 people in the UK (3), however for lots of people lifestyle and diet can play a key role. 

Type 2 diabetes and high cholesterol are closely linked and can be aided by dietary and lifestyle adjustments. In this article, we will discuss the relationship between these two conditions, how you can tailor your diet to help prevent or manage them, lifestyle factors that can contribute and the importance of checking in with your blood glucose and cholesterol.

What is their relationship?

These two health conditions are closely interlinked and can both significantly increase the risk of cardiovascular diseases on their own, and especially together (4). 

When blood glucose is elevated, the glucose molecules stick to your red blood cells causing glycated haemoglobin (HbA1c). These sticky blood cells can gather against blood vessel walls and cause deterioration of the cell walls (5). This can encourage the build-up of cholesterol molecules in the blood vessels too (5). Altogether, this affects the way the blood flows through your blood vessels which could have a negative impact on your heart health. 

Some of the shared risk factors for type 2 diabetes and high cholesterol include being obese or overweight, having an inactive lifestyle, smoking, excessive alcohol intake, increasing age, genetics and insulin resistance (whereby your body is unable to react to glucose in the blood effectively with insulin, meaning higher blood glucose and higher circulating insulin). Many people also have high blood glucose without being diabetic: prediabetes affects approximately 1 in 9 adults in England (6). 

What is interesting to note is that both high cholesterol and high blood glucose can be reversed, or ‘put into remission’. This can primarily be achieved by making appropriate lifestyle and diet changes that we are going to talk about. Please note, if you are looking to make significant changes, consult with a health professional before doing so.

What can you do in your diet to help? 

Diet plays a crucial role in managing both type 2 diabetes and high cholesterol by directly influencing blood glucose levels, lipid profiles, and body weight. Managing these is essential for preventing complications associated with these conditions as they can be protective for your heart health. Here are some ideas for foods beneficial to managing these conditions: 

Functional foods such as probiotics

Functional foods are foods that are produced with added ingredients that provide specific health benefits. Some branding may make you think a food is functional, but is just a health claim; whereas a functional food will have a scientifically proven benefit (7). An example of this is probiotics: live ‘friendly’ bacteria found in things like kimchi, sauerkraut, miso, tempeh, kombucha and kefir. It can help in cholesterol management by working in the gut, breaking down bile, stopping it being reabsorbed, as well as breaking down fibre into short-chain fatty acids which can reduce cholesterol production in the liver (8). In terms of type 2 diabetes, probiotics can help by diversifying gut microbiota, which can help with glucose metabolism and insulin sensitivity meaning HbA1c and fasting blood glucose levels can be improved (9). 

Plant stanols and sterols 

Plant stanols and sterols are natural compounds found in nuts, seeds, wholegrains and legumes, as well as being in fortified products such as Benecol. The structure of the compounds are similar to cholesterol, meaning they can interfere with cholesterol absorption, so more is lost in waste (10). It is suggested that 2g per day can help reach a level that provides the benefit of lowering LDL ‘bad’ cholesterol, without influencing HDL ‘good’ cholesterol (10). In terms of diabetes management, their direct effect is less well established, however the improvement of your blood lipids will naturally lower the risk of cardiovascular disease which is higher for those with type 2 diabetes. 

Limiting ultra-processed foods and consuming real, whole food 

In a world saturated with ultra-processed foods (UPF), there is more and more emphasis on eating real, whole foods wherever possible. This optimises the nutritional quality of what you’re eating as the real, whole foods are minimally processed so do not have added fats, sugars, salt and trans fats. This can in turn benefit heart health and increase satiety (11).

When building your meals, try and incorporate lean proteins, healthy fats and plenty of fibre. Protein increases satiety as well as being an important energy source. It helps you maintain and build muscle which is important for improving insulin sensitivity and thus management of blood glucose (12). Healthy fats such as extra-virgin olive oil, avocados, nuts, seeds and oily fish have beneficial effects for cholesterol by promoting the production of HDL cholesterol and help lower triglyceride levels (13). Wholegrains, fruits and vegetables are also important to add in as they provide fibre, of which we require at least 30g per day (14). This can be done by swapping white pasta, bread and rice to wholegrain versions, as well as including at least 5 fruit and vegetable portions per day. 

The Mediterranean diet is a good example of a diet made up of healthy fats like olive oil and oily fish, wholegrains, fruits and vegetables and limits highly processed foods such as processed meats and sugary soft drinks. This makes it a friendly approach to managing type 2 diabetes and high cholesterol (15). 

Lifestyle

There are plenty of lifestyle factors beyond nutrition that can contribute to high cholesterol and high blood glucose. For instance, stress, smoking, alcohol and limited physical exercise can all have negative impacts. 

Stress causes the release of cortisol and adrenaline which increase glucose production and in the long term can lead to increased HbA1c (16) as well as increasing LDL cholesterol and triglycerides and reducing HDL (17). Stress reduction techniques could include meditation, prioritising sleep, walking outside and creating a calming home environment by decluttering, but suffering with stress could lead to a reliance on smoking and alcohol which have a further undesirable impact. 

Smoking can have an adverse effect because nicotine can make cells less responsive to insulin, so blood glucose levels can increase (18). Studies have found that LDL cholesterol tends to be higher, and HDL cholesterol tends to be lower in smokers than non-smokers, which increases cardiovascular disease risk (19).

Long-term heavy consumption of alcohol can lead to insulin resistance by affecting the way the pancreas produces insulin (20). It can also affect the way the liver metabolises fats when consumed in excess, meaning LDL and triglycerides could be high and HDL could be low (21). 

Exercise improves insulin sensitivity (22) and manages cholesterol by increasing HDL and reducing HDL, as well as helping you manage weight which is important for heart health (23). So, when exercise is not done effectively, adverse effects can creep in. 

By tailoring your lifestyle to prioritise your blood glucose and cholesterol, you are setting yourself up to prevent cardiovascular diseases.

Importance of monitoring blood glucose and cholesterol

Regular monitoring of blood glucose and cholesterol helps screen for complications as well as identifying any changes. If you are making positive lifestyle changes to help manage your blood glucose and cholesterol, then this can be a rewarding way of seeing that the changes are working. But also, it allows you to understand what’s going on in your body better and seek further medical advice if required.

Some people will choose to use a continuous blood glucose monitor, or CGM, to track their blood glucose. You do not need to be diabetic to use one of these and can be a very enlightening way to see the rise and fall of your blood glucose. 

Many people use statins as a preventative medicine for high cholesterol: they are widely accepted and have considerable benefits in managing blood cholesterol (24), however, this does not mean that diet and lifestyle should not also be considered and adjusted, because if you were to come off the statins, their effect would not last (25).

Conclusion

Managing type 2 diabetes and high cholesterol can feel overwhelming, but small, consistent changes in your diet and lifestyle can lead to significant long-term improvements. Incorporating heart-healthy foods like lean proteins, wholegrains, fruit and vegetables and healthy fats, while reducing ultra-processed foods, can have a positive effect on both blood glucose and cholesterol levels. Additionally, regular physical activity, stress management, limiting alcohol and avoiding smoking are key factors in creating a healthy lifestyle.

By making gradual adjustments, you can improve your overall well-being and reduce the risk of cardiovascular complications. Regularly monitoring your cholesterol and blood glucose provides valuable insight and motivation as you continue to make these changes. 

If you have any more questions or would like personalised support, you can speak to an evidence-based registered nutritionist here:  Contact Us | Cirencester Nutrition   

References

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