Nutraceuticals for lowering cholesterol

Cholesterol is an important sterol involved in many body functions, however when cholesterol levels are elevated it can increase the risk for cardiovascular diseases. There are nutrients which, when combined with a healthy diet and exercise, can be used to help the body maintain healthy cholesterol levels.

Elevated cholesterol is implicated in cardiovascular disease – specifically atherosclerosis. Atherosclerosis is a chronic inflammatory condition which begins with deposits of cholesterol and fibrous tissues in the arterial walls. These plaques can build up and eventually cause narrowing and thickening of the artery, restricting blood flow. If they completely block the artery, heart attack or stroke can result.

What is cholesterol?

Cholesterol is a type of lipid/sterol (a waxy, fat-like substance) produced in the liver and provided by some foods. It is needed in the body for many functions important ones include as a precursor for the synthesis of steroid hormones, bile acids, and vitamin D; and the maintenance and integrity of cell membranes.

Cholesterol, triglycerides and fats are transported through blood (which is mainly water) by lipoproteins which are water repellent spherical structures with surface proteins needed for lipid metabolism.

There are several types of cholesterol, each containing varying degrees of cholesterol, proteins fats (triglycerides);  high-density lipoproteins, low-density lipoproteins, and very low-density lipoproteins.

High-density lipoproteins (HDL) is considered “good” cholesterol”. HDL's carry cholesterol from body tissues back to the liver where it can be removed from the body. High HDL cholesterol helps the body to regulate (and reduce) the cholesterol content of body tissues.

Low-density lipoproteins (LDL) move cholesterol from the liver to other areas of the body and is considered “bad” cholesterol. High LDL cholesterol can deposit in blood vessels, clog arteries and lead to stroke or heart attack.

Very low-density lipoproteins (VLDL). This cholesterol is released by the liver to provide body tissue with a type of fat (triglycerides). High levels of VLDL cholesterol have been implicated in plaque development on artery walls which narrow the passage and restrict blood flow. Note VLDL is hard to measure which is why it is not mentioned in regular regular screening tests for cholesterol. 

Triglycerides are made by the body and found in some foods you eat. They provide energy for metabolic processes. Food is converted to triglycerides for energy and any extra is stored in fat cells for release when energy from food is in low supply. A high dietary intake of fats, carbohydrates and alcohol can lead to high blood triglycerides [1].

Supporting healthy cholesterol levels

Diet and regular exercise, avoiding or reducing high sugar foods and alcohol, are the best ways of lowering triglycerides, and ultimately high levels of VLDL cholesterol. However, there are also some nutraceuticals which have been shown to help.

What is a nutraceutical?

A nutraceutical is defined as any substance that is a food or part of a food and provides medical or health benefits, including the prevention and treatment of disease.

Natural supplements target removal of cholesterol through reducing absorption, inhibiting production of cholesterol in the liver, and/or increasing good cholesterol [2,3,5].

Nutraceuticals for cholesterol reduction

• Beta glucan
• Plant sterols
• Soluble fibres
• Probiotics
• Bergamot (Citrus aurantium)
• Garlic (Allium sativum)
• Globe artichoke (Cynara scolymus) leaf extract
• Berberine
• Green tea extracts
• Turmeric
• Fish oil

Reduce absorption

Plant sterols – as the name implies, are a group of substancesfound in some plants. Plant sterols and cholesterol are similar in structure so they compete for absorption in the small intestine. Plant sterols reduce the absorption of cholesterol from dietary sources. They are found in high amount in vegetable oils, nuts, seeds and cereals; and as a supplement to lower cholesterol [5].

Beta glucans are polysaccharides found in various natural sources, such as mushrooms, oats and as a dietary supplement. They perform as dietary fibres in the digestive tract. β-glucans come in both insoluble and soluble fibre forms, and are able to combine with lipids and biliary salts in the bowel, resulting in a reduction of cholesterol levels [6].

Soluble fibres

• Oat bran
• Psyllium husks
• Glucomannan (konjac plant)

Probiotics are microorganisms which offer health benefits when taken in adequate amounts. One way in which probiotics are thought to reduce cholesterol is by binding or incorporating intestinal cholesterol into the bacterial cell membrane. In studies the best result was obtained from Lactobacillus strains in particular Lactobacillus acidophilus and Lactobacillus planetarium [2].

Inhibit the production of cholesterol in the liver

Bergamot is an oily substance extracted from the rind of the fruit of a dwarf variety of the Seville orange tree. It is high in antioxidant polyphenols, bruteridin and melitidin, which protect the body against free radical damage – including the vascular endothelium. The endothelium is the thin layer of cells lining blood vessels which is important in the constriction and dilation of the circulatory system (veins and arteries). Bergamot supports healthy cholesterol, healthy blood lipids, blood circulation and cardiovascular health [7}.

Allicin, found in garlic (Allium sativum), is responsible for the lipid-lowering effects. It is also thought it may promote bile acid secretion [2].

Berberine is a compound found in many plants, including European barberry (Berberis vulgaris), phellodendron (Phellodendron amurense), oregon grape (Mahonia aquifolium), goldenseal (Hydrastis canadensis), and goldthread. Their validated pharmacological effects include antimicrobial, anti-inflammatory, antioxidation, regulation of neurotransmitters and enzymes, and offers cholesterol-lowering effects [8,9].

Globe artichoke extract, obtained from the leaves of Cynara scolymus, offers strong antioxidant activity preventing oxidation of low-density lipoproteins (LDL’s), may inhibit the production of cholesterol, and has been shown to significantly reduce both total and LDL cholesterol and triglycerides [10].

Green tea extracts are rich in polyphenol antioxidants. The major fraction is catechins - including epigallocatechin-3-gallate (EGCG).

Green tea may lower LDL cholesterol, improve endothelial function and reduce arterial stiffness [2].

Other nutrients to consider

Curcuminoid - is a yellow pigment found in the root of turmeric (Curcuma longa). Several studies have demonstrated the protective effects of curcumin against many chronic diseases including CVD, and may improve serum lipid levels[11].

Fish oil (omega-3 fatty acids) may significantly reduce blood triglycerides levels and improve HDL however, it may also increase LDL cholesterol. Fish oil improves other cardiovascular risk factors [12].

Dietary guidelines

Dietary guidelines recommend eating as little as possible of dietary cholesterol and following a regular eating pattern. Interestingly, research has reported that increased intake of dietary cholesterol (exogenous) is associated with decreased synthesis of endogenous de novo cholesterol, possibly as a compensatory mechanism that keeps cholesterol homeostasis constant. In other words, the liver changes the amount of cholesterol it makes depending on how much your body absorbs from the diet. The more it absorbs the less it makes.

However, there is an abundance of evidence which implicates saturated fatty acids and trans-fats in an increase in the risk of cardiovascular disease. Dietary cholesterol is common in foods that are high in saturated fatty acids [13].

The information provided is not intended to be used for diagnosis or treatment. If you are experiencing any health concerns, please consult your doctor for advice.

References

1. VLDL cholesterol: Is it harmful? - Mayo Clinic
2. Nutraceuticals in the Management of Dyslipidemia: Which, When, and for Whom? Could Nutraceuticals Help Low-Risk Individuals with Non-optimal Lipid Levels? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8332568/
3. Preventing cardiovascular heart disease: Promising nutraceutical and non-nutraceutical treatments for cholesterol management https://www.sciencedirect.com/science/article/pii/S104366181631430X?via%3Dihub
4. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/nutraceutical
5. Phytosterols, Cholesterol Control, and cardiovascular disease  https://www.mdpi.com/2072-6643/13/8/2810
6.  β-glucans and cholesterol (Review) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5810204/
7. Clinical application of bergamot (Citrus bergamia) for reducing high cholesterol and cardiovascular disease markers https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6497409/#:~:text=Bergamot%20was%20observed%20to%20decrease,bergamot%20from%2050%20to%2054.
8. Effects of Berberine on Atherosclerosis https://www.frontiersin.org/articles/10.3389/fphar.2021.764175/full
9. Efficacy of Berberine Alone and in Combination for the Treatment of Hyperlipidemia: A Systematic Review https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5871262/
10. Lipid-lowering activity of artichoke extracts: A systematic review and meta-analysis https://pubmed.ncbi.nlm.nih.gov/28609140/
11. Efficacy and safety of turmeric and curcumin in lowering blood lipid levels in patients with cardiovascular risk factors: a meta-analysis of randomized controlled trials https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5637251/
12. An Improvement of Cardiovascular Risk Factors by Omega-3 Polyunsaturated Fatty Acids https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5827911/
13. Dietary Cholesterol and the Lack of Evidence in Cardiovascular Disease https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6024687/