Unravelling the Relationship Between the Keto Diet and Cholesterol

January 21, 2025

ESTIMATED READING TIME 6 MINUTES

Have you had a New Year health check to discover your cholesterol is on the high side? Or maybe you’ve heard about the health benefits of the keto diet and you’re thinking of trying it, but you’re worried how it may affect your cholesterol levels?

The relationship between the keto diet and cholesterol has become a subject of discussion, with conflicting viewpoints. In this article, we aim to cut through the confusion so you can make healthful choices.

First, it’s time for a little recap about cholesterol.

Understanding Cholesterol

It’s fair to say there’s been a lot of confusion and misinformation about cholesterol over the years. This is inevitable as science progresses and we learn things about the amazing human body that weren’t known before. Here at Embracing Nutrition we like to keep up to date with the latest scientific research, so we can make evidence-based healthful recommendation for our clients.

Cholesterol is a waxy substance found in your cells. For years, many people believed it was dangerous, because it can collect on the inside walls of arteries, causing blockages and cardiovascular issues. This has led to drugs like statins being developed, designed to drive down blood cholesterol, as well as medical advice – now discontinued – to avoid foods containing cholesterol.

However, as we began to discover more about cholesterol, a few things emerged. First, it’s made in your body, and it’s necessary for a whole host of essential processes in the body, from forming brain cells and hormones to vitamin D.

The second major discovery is that cholesterol can exist in several different forms. It travels through your bloodstream attached to two major types of lipoproteins:

High-density lipoprotein (HDL). Often known as ‘good’ cholesterol. Higher levels of HDL seem to be protective against heart disease.

Low-density lipoprotein (LDL). This is often known as ‘bad’ cholesterol. Elevated levels of LDL cholesterol are associated with the buildup of plaque in arteries, increasing the risk of heart disease. However, all LDL is not the same, because LDL particles vary in size, with smaller, denser particles (VLDL) being more likely to cause a build-up of plaque than larger ones.

The third aspect to bear in mind is that lipoproteins can be unoxidised or oxidised. If they’re oxidised this basically means they’ve been damaged by free radicals, unstable molecules created in your body when you produce energy. Oxidised lipoproteins can stick more readily to the inside of your arteries. Meanwhile, oxidative damage caused by inflammation can cause the linings of your arteries to become less smooth than they should be. This means cholesterol deposits accumulate more easily.

The Keto Diet Explained

Ketogenic eating has increased in popularity in recent years. The main principle of keto is to reduce the amount of carbohydrates in the diet, while eating plenty of fat and moderate amounts of protein.

Typically, the breakdown of macronutrients in the diet is around 70-80% fat, 10-25% protein, and 5-10% carbohydrates.

Practically speaking, this means consuming only around 20-50g carbohydrates per day.

Eating this way causes the body to enter a state called ketosis. This occurs when it burns fat for fuel rather than carbs. Substances called ketone bodies are produced by the liver and used for energy.

Ketosis has various metabolic effects on the body, and people eating a keto diet typically report weight loss, improved mental clarity and increased energy.

A combination of factors is likely contributing to this. Removing refined carbohydrates is known to improve blood sugar control and nourish the microbiome. Both of these have wide-ranging positive effects on health. At the same time, many people don’t realise they’re sensitive to grains, so avoiding them can mean they feel better.

However, because of the amount of fat eaten when on a keto diet, the question of how it could impact cholesterol levels is an important one.

The Effects of Keto Eating on Cholesterol

The keto diet is a great help in reducing excess weight. This on its own is connected with many health benefits, including reduced risk of cardiovascular disease. However, the diet’s effects on blood fats are not solely down to its impact on weight loss.

Research following people adopting a keto diet has found that in the initial stages of their new way of eating, cholesterol can increase. This applies particularly to LDL, which ideally should be low. It’s possibly due to triglycerides being metabolised for fuel, impacting cholesterol levels in the short term ¹

This has led to some criticism of the keto diet. However, looking at the research overall, after a while the raised total cholesterol and LDL levels seem to reduce again ². And don’t forget, it’s the small dense LDL which is correlated with cardiovascular issues. A keto diet appears to reduce these VLDL levels while increasing the LDL with larger particle sizes ³. Meanwhile, the diet seems to generally raise HDL levels, which is positive.

The other aspect to consider is triglyceride levels. These are fats the body can use for energy or store for later. Elevated levels of triglycerides are linked to an increased risk of heart disease. The keto diet has been seen to reduce blood triglycerides ⁴.

Finally, the ketogenic diet can reduce uncontrolled inflammation and insulin resistance ⁵, both linked with poor cardiovascular health.

Healthy Keto Eating

As with any way of eating, there are healthy keto diets and there are unhealthy ones. You need to be sure you are consuming plenty of plant foods to provide vital fibre for your gut bacteria, along with the plant polyphenols so important for health.

The other important choice surrounds fats. Fats from animal sources contain a high percentage of saturated fats. Certain saturated fats are known to increase cholesterol levels. Much better to consume monounsaturated and polyunsaturated fats, known to have beneficial effects on cholesterol levels and cardiovascular health in general ⁶.

The varying quality of the keto diets used in research has probably contributed towards the confusing scientific findings.

If you are interested in trying keto eating, bear these points in mind:

Incorporating healthy fats is key. Choose fats from oily fish, avocados, fresh nuts, seeds, coconut, and extra virgin olive oil. Limit those saturated fats found in meat, dairy and fried foods.
Keep fibre intake high. This means consuming plenty of low-carb veggies such as tomatoes, asparagus, broccoli and spinach, kale, cauliflower, peppers, and courgette, and fruit such as berries.
Emphasise healthy proteins like eggs, oily fish, poultry, and grass-fed meats.

This type of eating combines the ketogenic diet with aspects of the Mediterranean diet.

If you would like to explore keto eating for yourself, we have a fabulous range of delicious recipes in our FREE Keto Cookbook (requires free account to access E-books)

Do speak to your practitioner if you suffer from any health condition such as diabetes; familial hypercholesterolaemia, an inherited high cholesterol picture; or you’re on any medical drugs, before embarking on the keto diet.

Of course, diet is not the only piece of the jigsaw when it comes to cholesterol management and overall good health. Genetics, physical activity, stress, and sleep all play significant roles. Functional testing can be used to determine whether your blood fats are in a healthy ratio, or if other aspects are hindering your cardiovascular health.

If you’re concerned about cholesterol and would like to explore some natural ways to support your health, why not book a free discovery call today?