CHOLESTEROL
Natural cholesterol-lowering products: focus on probiotics Punita Mistry
The University of Nottingham, The Royal Wolverhampton NHS Trust, Medicines Management Dietitian, Nutrition and Dietetic Department, New Cross Hospital, Wolverhampton Email: [email protected]
C
ardiovascular disease (CVD) is responsible for one third of deaths in England and Wales and was estimated to cost the NHS £7880 million in 2010 (National Institute for Health and Care Excellence (NICE), 2014). Death rates from CVD have been falling since the 1980s, and in the last 10 years have fallen by 44% for under 75 year olds in the UK (Townsend et al, 2012). This is thought to be largely due to a reduction in smoking, as well as an increase in the use of lipid-lowering medication (Unal et al, 2004). However, CVD is the second highest cause of death in the UK (the leading cause being cancer, only beating CVD by 1%) (Office for National Statistics, 2014); and therefore it is important that any risk factors that are modifiable, such as cholesterol, are controlled as best as possible. In fact, the risk of heart attack is thought to be three-times higher in those with raised cholesterol levels (World Health Organization (WHO), 2013). A healthy diet should be encouraged to the population to prevent cholesterol levels from being raised. However, there are also natural products that can help to actively lower cholesterol levels once raised. Although they have been available for many years, as more research is carried out in this area there are a growing number of widely available foods that have demonstrably lowered cholesterol. Probiotics
are commonly known for improving gut function by providing extra ‘good bacteria’ (Goldenberg et al, 2013), but there is growing evidence that has shown that they could also be involved in lowering cholesterol levels (DiRienzo, 2014). It needs to be decided whether they can play as significant a role in improving lipid profiles as cholesterol-lowering medication does.
What is cholesterol? Cholesterol is a type of fat which is involved in building new cells, insulating nerves, and has a key role in hormone production (Birtcher et al, 2004). Lipoproteins are molecules that carry cholesterol and other substances in the blood. Low-density lipoprotein (LDL), often known as ‘bad cholesterol’ carries cholesterol from the liver to where it is needed in the body. It can build up in arterial walls resulting in atherosclerosis and an increased risk of CVD. High–density lipoprotein (HDL), which is sometimes referred to as ‘good cholesterol’, carries cholesterol from the cells back to the liver where it is broken down or excreted (Birtcher et al, 2004). Updated NICE guidelines have recommended measuring non-HDL cholesterol (total cholesterol minus HDL cholesterol) instead of LDL cholesterol for a better evaluation of lipid profile (NICE, 2014).
Managing cholesterol levels
It is important to maintain healthy blood lipid profiles in order to reduce risk of cardiovascular disease. This article explores some of the evidence for natural cholesterol lowering products as a possible alternative to cholesterol lowering medication. Probiotics have been investigated for their effect on cholesterol levels and there is increasing evidence to support their use as a natural cholesterol lowering alternative.
KEY WORDS
w Cholesterol w Probiotics w Natural foods w Health
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Modifiable lifestyle factors Alongside any medication, a cardio-protective diet and healthy lifestyle should be encouraged. Recommendations include: Fat intake to be 30% or less of total energy intake Saturated fat intake to be 7% or less of total energy intake Dietary cholesterol to be less than 300 mg per day Saturated fats, where possible, should be replaced by monounsaturated or polyunsaturated fats At least 5 portions of fruit and vegetables per day
© 2014 MA Healthcare Ltd
ABSTRACT
There are many factors that affect cholesterol; some of these being non-modifiable (e.g. age, ethnic group) and modifiable lifestyle factors (e.g. smoking, excess alcohol intake, diet and exercise).
Nutrition, October 2014
Journal of Community Nursing. Downloaded from magonlinelibrary.com by 130.113.111.210 on September 28, 2015. For personal use only. No other uses without permission. . All rights re
CHOLESTEROL Two portions of fish per week, to include one portion of oily fish (omega-3 supplements are no longer recommended as studies have shown that they do not help to significantly lower CVD risk) Alcohol intake to be within recommended limits (no more than 3–4 units per day for men, 2–3 units for women) Regular exercise aiming for a minimum of 150 minutes of moderate intensity activity or 75 minutes of vigorous intensity activity per week Smoking cessation (NICE, 2014).
Cholesterol-lowering medication Statins are a class of medication that are most commonly used to help significantly lower cholesterol levels. Studies have shown that they are able to reduce the risk of ischaemic heart disease by 60% and stroke by 17% (Law et al, 2003). Updated NICE guidelines recommend lowering the threshold as to when these are initiated, starting from when a patient is at 10% risk of developing CVD in the next 10 years, instead of the previous advice to initiate when at 20% risk (NICE, 2014). Statins work by inhibiting an enzyme involved in cholesterol synthesis in the liver. They will also cause a higher expression of LDL receptors in the liver so there will be less LDL circulating in the blood plasma (Vaughan et al, 1996). However, there are reported side effects of statins, the most common being myopathy (ranging from muscle weakness to severe muscular pain), which affects 0.1–0.2 % of people taking statins, and more serious side effects, such as rhabdomyolysis. However, fatal rhabdomyolysis is thought to affect less than one death per one million prescriptions for all statins, excluding cerivastatin (Bellosta et al, 2004). Although this suggests that side effects are not very common, compliance with statins has been shown to decrease over time and a study has shown a 26% rate of non-compliance in patients with CVD, which was associated with an 85% increase in mortality (Ho et al, 2008). There is no guarantee that patient compliance with natural cholesterol-lowering substances would be better, but having a natural alternative product may be preferred by some people.
Natural cholesterollowering products
© 2014 MA Healthcare Ltd
Phytostanols and phytosterols If individuals feel that they cannot manage their cholesterol levels with healthy eating alone, plant sterols or stanols (or phytosterols and phytostanols) could be tried. These are a class of functional foods; which have beneficial health effects outside their basic nutritional properties (Hasler, 2000). As their names suggest, they are of plant origin so are found naturally in fruits, vegetables, vegetable oils, seeds and nuts. In these whole foods they are only found in very small quantities, particularly the phytostanols, with daily intake estimated to be between 150–400 mg (Kidambi and Patel, 2008). However, it has been recommended that in order for any beneficial
Nutrition, October 2014
Bio-Kult is a scientifically developed, advanced multi-strain formula containing 14 live bacterial cultures, proven to survive the high acidity of the stomach. Bio-Kult is suitable for vegetarians and it’s gluten free. It can be swallowed whole, sprinkled over food or mixed in a drink and it doesn’t need to be refrigerated.
Ask your wholesaler for more information, or contact Bio-Kult.
S15
Journal of Community Nursing. Downloaded from magonlinelibrary.com by 130.113.111.210 on September 28, 2015. For personal use only. No other uses without permission. . All rights re
CHOLESTEROL
KEY POINTS
w It is important to maintain healthy levels of cholesterol to reduce risk of cardiovascular disease
w A healthy diet and lifestyle can help to manage lipid profiles w Plant phytosterols and stanols have been shown to reduce levels of cholesterol if taken in sufficient quantity as part of a balanced diet
w There is potential for probiotics to influence levels although the mechanism by which this works in not yet well understood
w More research is needed in this area as current literature is conflicting
S16
intervention in reducing cardiovascular events (NICE, 2014). However, these products are widely available and it is important that the public have a full understanding of their potential role in managing lipid profiles.
Probiotics Another natural product that could have a role in lowering cholesterol levels are probiotics. These are live microorganisms that provide a health benefit to the host when taken in sufficient quantities (Food and Agriculture Organization of the United Nations (FAO)-WHO, 2001) and are commonly described as ‘good bacteria’. They are usually found in yoghurts (or yoghurt drinks e.g. Yakult and Actimel Plus), but are also available in other forms (capsule or powder). Although probiotics have been shown to provide various health benefits, they are probably most well known for preventing antibiotic related diarrhoea, by helping to restore gut bacteria which are often destroyed when taking antibiotics. They have been shown to reduce the risk of developing Clostridium difficile infection when taken alongside antibiotics (Goldenberg et al, 2013). There have been various clinical trials that have identified specific strains of probiotics which lower LDL cholesterol. Examples include: L. reuteri NCIMB 30242 which has been shown to reduce LDL cholesterol by 8.9–11.6%, and is believed to have a similar effect as phytosterols/stanols (Jones et al, 2012). A review concluded that this strain of probiotic has the most evidence to support its use in lowering cholesterol levels (DiRienzo, 2014) E. faecium has shown that it can reduce LDL cholesterol by 5%. However, there is a safety concern regarding its use as a food ingredient (Bertolami et al, 1999). L. acidophilus showed a 2.4% decline in plasma cholesterol levels (Anderson et al, 1999). This indicates that there is variation in the effect, depending on the strain of probiotic used. A meta-analysis concluded that a diet rich in probiotics can significantly reduce total cholesterol by 6.4 mg/dl (0.16 mmol/L) and LDL cholesterol by 4.9 mg/dl (0.13 mmol/L) (Zhuang et al, 2012). However, other research indicates minimal or nil effect on blood lipid profiles (Hatakka et al, 2008). Similarly, prebiotics (which are non-digestible food ingredients that stimulate the growth of beneficial microorganisms in the gut) have also been shown to lower cholesterol, which is likely to be due to their role in promoting the growth of probiotics, as well as decreasing cholesterol absorption. The use of both prebiotics and probiotics together (synbiotics) has also been investigated and some research has demonstrated a significant lowering of LDL cholesterol or increases in HDL cholesterol (Kießling et al, 2002). Again, there is other research which shows insignificant effects on cholesterol levels. It is thought that different combinations of different strains of bacteria all have different effects and so before recommendations are made of their beneficial effects, further understanding of dosage and combination is required.
© 2014 MA Healthcare Ltd
effects to be seen, 1.3 g per day of sterols or 1.7 g per day of stanols is needed (Hasler et al, 2004). Therefore, fortified foods are available which offer adequate levels of sterols and stanols that are more likely to result in any beneficial effects occurring. The most commonly known fortified products include Benecol, Flora proactiv or Danone Danacol yoghurt drinks. They are also available as margarine spreads (Benecol or Flora proactiv). These products can be consumed alongside the use of cholesterol-lowering drugs, such as statins. The mechanisms by which each of these methods works to lower cholesterol are different, and so the use of both could optimise the reduction in LDL levels (Webb, 2006). As previously mentioned, statins lower LDL cholesterol by inhibiting an enzyme which is involved in the synthesis of cholesterol in the liver. In comparison, phytosterols are poorly absorbed in the gut and phytostanols even more so. However, this results in them being able to inhibit the absorption of dietary cholesterol by 30-50% (Webb, 2006). Moreover, it has been suggested that the re-absorption of biliary cholesterol is also reduced (Webb 2006). Both of these processes will decrease absorption and result in more cholesterol being lost in faeces. The effect of reduced absorption is only on LDL cholesterol, but HDL levels are kept at the same level (Jones et al, 2000). A metaanalysis performed from 41 clinical trials suggested that LDL cholesterol could be reduced by 10% if 2 g of either stanols or sterols are eaten every day (Katan et al, 2003). However, it is important to note that this reduction is not as significant when compared to consuming statins. The beneficial effects resulting from plant sterols and stanols are only seen when an individual has high levels of LDL cholesterol. It is recommended that these products will only have optimum health benefits when used as part of a healthy diet and lifestyle (Jones et al, 2000). Additionally, they need to be consumed in the doses recommended (e.g. one bottle of yoghurt drink per day) and taken consistently for these beneficial effects to occur. The main disadvantage of these products is that they are expensive compared to non-fortified alternatives and statins. Note that NICE guidelines cannot recommend for patients to take these products for the primary or secondary prevention of CVD, as there is minimal evidence regarding the effectiveness of
Nutrition, October 2014
Journal of Community Nursing. Downloaded from magonlinelibrary.com by 130.113.111.210 on September 28, 2015. For personal use only. No other uses without permission. . All rights re
CHOLESTEROL individual would need to take probiotics for and also which strains of bacteria have any beneficial effects (DiRienzo, 2014). Therefore, further clinical evidence is needed in this area before recommendations can be made. In addition, there have been reported incidences of probiotics causing systemic infection in immunocompromised individuals (Ooi et al, 2010). Moreover, certain strains of probiotics have shown antibiotic resistance and so the safety and dosage needs to be considered before widespread use is recommended.
Conclusion Randomised trials have found that if LDL cholesterol is reduced by 1.6 mmol/L, then after 2 years this can halve the risk of ischaemic heart disease (IHD) events (Law et al, 2003). This same study has found that statins can lower LDL cholesterol by 1.8 mmol/L, demonstrating they are an effective treatment. We need to understand how much phytostanols, sterols and probiotics can reduce LDL cholesterol by, in order to measure up their effectiveness compared to current medication as a natural alternative. Current literature is conflicting and does not suggest that these natural products have as significant an effect on lipid profiles, but could be used in addition to cholesterol-lowering medication, or for those who do not tolerate the medication or prefer to choose a more natural treatment. Further research in this area is required before probiotics can be suggested as a treatment as we do not know which specific strains and dosage
© 2014 MA Healthcare Ltd
© Lucie Carlier
The mechanism by which probiotics affect cholesterol is not well understood, although several theories have been suggested. A review suggested that the accepted theory is that probiotics inhibit intestinal cholesterol absorption and that it suppresses bile acid reabsorption (Zhuang et al, 2012). The theory of bile acid reabsorption having an effect has further been supported by DiRienzo (2014). There has been recent evidence that carnitine (a quaternary ammonium compound, derived from amino acids), found in red meat and dairy products, is also responsible for raising LDL cholesterol levels (Koeth et al, 2013). This is thought to be a hidden contributor to raising cholesterol levels, as for many decades it has been understood that it is the saturated fat in red meat that affects LDL. Early work in rodents by Koeth et al (2013) has shown that the breakdown of carnitine results in increased colonisation of bacteria in the gut and formation of trimethylamine N-oxide (TMAO) metabolite, which promotes cholesterol deposition (Koeth et al, 2013). This is possibly a method in which probiotics might help lower cholesterol levels as they could help to balance the gut flora and counter the actions of carnitine. Further evidence of this is needed in human studies and it is a growing area of interest. The evidence for the use of probiotics in lowering LDL cholesterol is conflicting, with some studies showing an improvement in lipid profiles and others showing insignificant effects. There is minimal evidence to show what dosage is required for any effect, the duration an
A healthy diet and lifestyle can help to manage lipid profiles
Nutrition, October 2014
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CHOLESTEROL of probiotics is required. Another factor to consider is cost. These natural products could be purchased by the individual, rather than having a cholesterollowering medication prescribed, saving the NHS money at a time when medicines management savings projects are growing. Alongside any intervention, it is key that healthy eating recommendations and lifestyle changes are also implemented to help manage cholesterol levels. BJCN Anderson J, Gilliland S (1999) Effect of fermented milk (yoghurt) containing Lactobacillus acidophilus L1 on serum cholesterol in hypercholesterolemic humans. J Am Coll Nutr 18(1): 43–50 Bellosta S, Paoletti R, Corsini A (2004) Safety of statins focus on clinical pharmacokinetics and drug interactions. Circulation 109(23 Suppl 1): III50–7 Bertolami M, Faludi A, Batlouni M (1999) Evaluation of the effects of a new fermented milk product (Gaio) on primary hypercholesterolemia. Eur J Clin Nutr 53(2): 97–101 Birtcher K, Ballantyne C (2004) Measurement of cholesterol: a patient perspective. Circulation 110: 296–7 DiRienzo D (2014) Effect of probiotics on biomarkers of cardiovascular disease: implications for heart-healthy diets. Nutr Rev 72(1): 18–29. doi: 10.1111/nure.12084 Food and Agriculture Organization of the United Nations and World Health Organization (2001) Report on Joint FAO/ WHO expert consultation on evaluation of health and nutritional properties of probiotics in food including powder milk with live lactic acid bacteria. http://tinyurl.com/8bccc3r (accessed 24 September 2014) Goldenberg J, Ma S, Saxton J et al (2013) Probiotics for the prevention of Clostridium difficile-associated diarrhoea in adults and children. Cochrane Database Syst Rev 5: CD006095. doi: 10.1002/14651858.CD006095.pub3 Hasler C (2000) The changing face of functional foods. J Am Coll Nutr 19(5 Suppl): 499S–506S Hasler C, Bloch A, Thomson C, Enrione E, Manning C (2004) Position of the American Dietetic Association: Functional foods. J Am Diet Assoc, 104, 814-26 Hatakka K, Mutanen, M., Holma R, Saxelin M, Korpela R (2008) Lactobacillus rhamnosus LC705 together with Propionibacterium freudenreichii ssp shermanii JS Administered in capsules is ineffective in lowering serum lipids. J Am Coll Nutr 27(4): 441–7 Jones P, Raeini-Sarjaz M, Ntanios F, Vanstone C, Feng J, Parsons W (2000) Modulation of plasma lipid levels and cholesterol kinetics by phytosterol
versus phytostanol esters. J Lipid Res 41(5):697–705 Jones M, Martoni C, Parent M (2012) Cholesterol-lowering efficacy of a microencapsulated bile salt hydrolase-active Lactobacillus reuteri NCIMB 30242 yoghurt formulation in hypercholesterolaemic adults. Br J Nutr 107(10): 1505–13. doi: 10.1017/S0007114511004703 Katan M., Grundy S, Jones P et al (2003) Efficacy and safety of plant stanols and sterols in the management of blood cholesterol levels. Mayo Clin Proc 78(8): 965–78 KeiBling G, Schneider J, Jahreis G (2002) Long-term consumption of Fermented Dairy Products over 6 months increases HDL Cholesterol. Eur J Clin Nutr 56(9): 843–9 Kidambi S, Patel S (2008) Sitosterolaemia: pathophysiology, clinical presentation and laboratory diagnosis. J Clin Pathol 61(5): 588–94. doi: 10.1136/ jcp.2007.049775 Koeth R, Wang Z, Levison B (2013) Intestinal microbiota metabolism of l-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med 19(5): 576–85. doi: 10.1038/nm.3145 Law M., Wald N, Rudnicka A (2003) Quantifying effect of statins on low density lipoprotein cholesterol, ischaemic heart disease, and stroke: systemic review and meta-analysis. BMJ 326(7404): 1423 National Institute for Health and Care Excellence (2014) Lipid Modification: cardiovascular risk assessment and the modification of blood lipids for the primary and secondary prevention of cardiovascular disease. Guideline CG181. http://tinyurl.com/l8t9nez (accessed 24 September 2014) Office of National Statisitcs (2014) Cancer. http://tinyurl.com/k3tyexn (accessed 24 September 2014) Ooi L, Liong M. (2010) Cholesterol lowering effects of Probiotics and Prebiotics: A Review of in Vivo and in Vitro Findings. Int J Mol Sci 11(6): 2499–522. doi: 10.3390/ijms11062499 Townsend N, Wickramasinghe K, Bhatnagar P, Smolina (2012) Coronary heart disease statistics: A compendium of health statistics - 2012 edition. http:// tinyurl.com/mzdd56t (accessed 24 September 2014) Unal B, Critchley J, Capewell S (2004) Explaining the Decline in Coronary Heart Disease Mortality between 1981 and 2000. Circulation 109(9): 1101–7 Vaughan C, Murphy M and Buckley B (1996) Statins do more than just lower cholesterol. Lancet 348(9034):1079–82 Webb G (2006) Dietary Supplements and Functional Foods. 1st edn. Blackwell Publishing, Oxford: 207–11 World Health Organization (2013) Cardiovascular disease; Fact sheet No 317, http://tinyurl.com/br89ujf (accessed 24 September 2014) Zhuang G, Liu X, Zhang Q, Tian F et al (2012) Research advances with regards to clinical outcomes and potential mechanisms of the cholesterol-lowering effects of probiotics. Clinical Lipidology 7(5): 501–7. doi:10.2217/clp.12.40
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Nutrition, October 2014
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Natural cholesterol-lowering products: focus on probiotics Punita Mistry
The University of Nottingham, The Royal Wolverhampton NHS Trust, Medicines Management Dietitian, Nutrition and Dietetic Department, New Cross Hospital, Wolverhampton Email: [email protected]
C
ardiovascular disease (CVD) is responsible for one third of deaths in England and Wales and was estimated to cost the NHS £7880 million in 2010 (National Institute for Health and Care Excellence (NICE), 2014). Death rates from CVD have been falling since the 1980s, and in the last 10 years have fallen by 44% for under 75 year olds in the UK (Townsend et al, 2012). This is thought to be largely due to a reduction in smoking, as well as an increase in the use of lipid-lowering medication (Unal et al, 2004). However, CVD is the second highest cause of death in the UK (the leading cause being cancer, only beating CVD by 1%) (Office for National Statistics, 2014); and therefore it is important that any risk factors that are modifiable, such as cholesterol, are controlled as best as possible. In fact, the risk of heart attack is thought to be three-times higher in those with raised cholesterol levels (World Health Organization (WHO), 2013). A healthy diet should be encouraged to the population to prevent cholesterol levels from being raised. However, there are also natural products that can help to actively lower cholesterol levels once raised. Although they have been available for many years, as more research is carried out in this area there are a growing number of widely available foods that have demonstrably lowered cholesterol. Probiotics
are commonly known for improving gut function by providing extra ‘good bacteria’ (Goldenberg et al, 2013), but there is growing evidence that has shown that they could also be involved in lowering cholesterol levels (DiRienzo, 2014). It needs to be decided whether they can play as significant a role in improving lipid profiles as cholesterol-lowering medication does.
What is cholesterol? Cholesterol is a type of fat which is involved in building new cells, insulating nerves, and has a key role in hormone production (Birtcher et al, 2004). Lipoproteins are molecules that carry cholesterol and other substances in the blood. Low-density lipoprotein (LDL), often known as ‘bad cholesterol’ carries cholesterol from the liver to where it is needed in the body. It can build up in arterial walls resulting in atherosclerosis and an increased risk of CVD. High–density lipoprotein (HDL), which is sometimes referred to as ‘good cholesterol’, carries cholesterol from the cells back to the liver where it is broken down or excreted (Birtcher et al, 2004). Updated NICE guidelines have recommended measuring non-HDL cholesterol (total cholesterol minus HDL cholesterol) instead of LDL cholesterol for a better evaluation of lipid profile (NICE, 2014).
Managing cholesterol levels
It is important to maintain healthy blood lipid profiles in order to reduce risk of cardiovascular disease. This article explores some of the evidence for natural cholesterol lowering products as a possible alternative to cholesterol lowering medication. Probiotics have been investigated for their effect on cholesterol levels and there is increasing evidence to support their use as a natural cholesterol lowering alternative.
KEY WORDS
w Cholesterol w Probiotics w Natural foods w Health
S14
Modifiable lifestyle factors Alongside any medication, a cardio-protective diet and healthy lifestyle should be encouraged. Recommendations include: Fat intake to be 30% or less of total energy intake Saturated fat intake to be 7% or less of total energy intake Dietary cholesterol to be less than 300 mg per day Saturated fats, where possible, should be replaced by monounsaturated or polyunsaturated fats At least 5 portions of fruit and vegetables per day
© 2014 MA Healthcare Ltd
ABSTRACT
There are many factors that affect cholesterol; some of these being non-modifiable (e.g. age, ethnic group) and modifiable lifestyle factors (e.g. smoking, excess alcohol intake, diet and exercise).
Nutrition, October 2014
Journal of Community Nursing. Downloaded from magonlinelibrary.com by 130.113.111.210 on September 28, 2015. For personal use only. No other uses without permission. . All rights re
CHOLESTEROL Two portions of fish per week, to include one portion of oily fish (omega-3 supplements are no longer recommended as studies have shown that they do not help to significantly lower CVD risk) Alcohol intake to be within recommended limits (no more than 3–4 units per day for men, 2–3 units for women) Regular exercise aiming for a minimum of 150 minutes of moderate intensity activity or 75 minutes of vigorous intensity activity per week Smoking cessation (NICE, 2014).
Cholesterol-lowering medication Statins are a class of medication that are most commonly used to help significantly lower cholesterol levels. Studies have shown that they are able to reduce the risk of ischaemic heart disease by 60% and stroke by 17% (Law et al, 2003). Updated NICE guidelines recommend lowering the threshold as to when these are initiated, starting from when a patient is at 10% risk of developing CVD in the next 10 years, instead of the previous advice to initiate when at 20% risk (NICE, 2014). Statins work by inhibiting an enzyme involved in cholesterol synthesis in the liver. They will also cause a higher expression of LDL receptors in the liver so there will be less LDL circulating in the blood plasma (Vaughan et al, 1996). However, there are reported side effects of statins, the most common being myopathy (ranging from muscle weakness to severe muscular pain), which affects 0.1–0.2 % of people taking statins, and more serious side effects, such as rhabdomyolysis. However, fatal rhabdomyolysis is thought to affect less than one death per one million prescriptions for all statins, excluding cerivastatin (Bellosta et al, 2004). Although this suggests that side effects are not very common, compliance with statins has been shown to decrease over time and a study has shown a 26% rate of non-compliance in patients with CVD, which was associated with an 85% increase in mortality (Ho et al, 2008). There is no guarantee that patient compliance with natural cholesterol-lowering substances would be better, but having a natural alternative product may be preferred by some people.
Natural cholesterollowering products
© 2014 MA Healthcare Ltd
Phytostanols and phytosterols If individuals feel that they cannot manage their cholesterol levels with healthy eating alone, plant sterols or stanols (or phytosterols and phytostanols) could be tried. These are a class of functional foods; which have beneficial health effects outside their basic nutritional properties (Hasler, 2000). As their names suggest, they are of plant origin so are found naturally in fruits, vegetables, vegetable oils, seeds and nuts. In these whole foods they are only found in very small quantities, particularly the phytostanols, with daily intake estimated to be between 150–400 mg (Kidambi and Patel, 2008). However, it has been recommended that in order for any beneficial
Nutrition, October 2014
Bio-Kult is a scientifically developed, advanced multi-strain formula containing 14 live bacterial cultures, proven to survive the high acidity of the stomach. Bio-Kult is suitable for vegetarians and it’s gluten free. It can be swallowed whole, sprinkled over food or mixed in a drink and it doesn’t need to be refrigerated.
Ask your wholesaler for more information, or contact Bio-Kult.
S15
Journal of Community Nursing. Downloaded from magonlinelibrary.com by 130.113.111.210 on September 28, 2015. For personal use only. No other uses without permission. . All rights re
CHOLESTEROL
KEY POINTS
w It is important to maintain healthy levels of cholesterol to reduce risk of cardiovascular disease
w A healthy diet and lifestyle can help to manage lipid profiles w Plant phytosterols and stanols have been shown to reduce levels of cholesterol if taken in sufficient quantity as part of a balanced diet
w There is potential for probiotics to influence levels although the mechanism by which this works in not yet well understood
w More research is needed in this area as current literature is conflicting
S16
intervention in reducing cardiovascular events (NICE, 2014). However, these products are widely available and it is important that the public have a full understanding of their potential role in managing lipid profiles.
Probiotics Another natural product that could have a role in lowering cholesterol levels are probiotics. These are live microorganisms that provide a health benefit to the host when taken in sufficient quantities (Food and Agriculture Organization of the United Nations (FAO)-WHO, 2001) and are commonly described as ‘good bacteria’. They are usually found in yoghurts (or yoghurt drinks e.g. Yakult and Actimel Plus), but are also available in other forms (capsule or powder). Although probiotics have been shown to provide various health benefits, they are probably most well known for preventing antibiotic related diarrhoea, by helping to restore gut bacteria which are often destroyed when taking antibiotics. They have been shown to reduce the risk of developing Clostridium difficile infection when taken alongside antibiotics (Goldenberg et al, 2013). There have been various clinical trials that have identified specific strains of probiotics which lower LDL cholesterol. Examples include: L. reuteri NCIMB 30242 which has been shown to reduce LDL cholesterol by 8.9–11.6%, and is believed to have a similar effect as phytosterols/stanols (Jones et al, 2012). A review concluded that this strain of probiotic has the most evidence to support its use in lowering cholesterol levels (DiRienzo, 2014) E. faecium has shown that it can reduce LDL cholesterol by 5%. However, there is a safety concern regarding its use as a food ingredient (Bertolami et al, 1999). L. acidophilus showed a 2.4% decline in plasma cholesterol levels (Anderson et al, 1999). This indicates that there is variation in the effect, depending on the strain of probiotic used. A meta-analysis concluded that a diet rich in probiotics can significantly reduce total cholesterol by 6.4 mg/dl (0.16 mmol/L) and LDL cholesterol by 4.9 mg/dl (0.13 mmol/L) (Zhuang et al, 2012). However, other research indicates minimal or nil effect on blood lipid profiles (Hatakka et al, 2008). Similarly, prebiotics (which are non-digestible food ingredients that stimulate the growth of beneficial microorganisms in the gut) have also been shown to lower cholesterol, which is likely to be due to their role in promoting the growth of probiotics, as well as decreasing cholesterol absorption. The use of both prebiotics and probiotics together (synbiotics) has also been investigated and some research has demonstrated a significant lowering of LDL cholesterol or increases in HDL cholesterol (Kießling et al, 2002). Again, there is other research which shows insignificant effects on cholesterol levels. It is thought that different combinations of different strains of bacteria all have different effects and so before recommendations are made of their beneficial effects, further understanding of dosage and combination is required.
© 2014 MA Healthcare Ltd
effects to be seen, 1.3 g per day of sterols or 1.7 g per day of stanols is needed (Hasler et al, 2004). Therefore, fortified foods are available which offer adequate levels of sterols and stanols that are more likely to result in any beneficial effects occurring. The most commonly known fortified products include Benecol, Flora proactiv or Danone Danacol yoghurt drinks. They are also available as margarine spreads (Benecol or Flora proactiv). These products can be consumed alongside the use of cholesterol-lowering drugs, such as statins. The mechanisms by which each of these methods works to lower cholesterol are different, and so the use of both could optimise the reduction in LDL levels (Webb, 2006). As previously mentioned, statins lower LDL cholesterol by inhibiting an enzyme which is involved in the synthesis of cholesterol in the liver. In comparison, phytosterols are poorly absorbed in the gut and phytostanols even more so. However, this results in them being able to inhibit the absorption of dietary cholesterol by 30-50% (Webb, 2006). Moreover, it has been suggested that the re-absorption of biliary cholesterol is also reduced (Webb 2006). Both of these processes will decrease absorption and result in more cholesterol being lost in faeces. The effect of reduced absorption is only on LDL cholesterol, but HDL levels are kept at the same level (Jones et al, 2000). A metaanalysis performed from 41 clinical trials suggested that LDL cholesterol could be reduced by 10% if 2 g of either stanols or sterols are eaten every day (Katan et al, 2003). However, it is important to note that this reduction is not as significant when compared to consuming statins. The beneficial effects resulting from plant sterols and stanols are only seen when an individual has high levels of LDL cholesterol. It is recommended that these products will only have optimum health benefits when used as part of a healthy diet and lifestyle (Jones et al, 2000). Additionally, they need to be consumed in the doses recommended (e.g. one bottle of yoghurt drink per day) and taken consistently for these beneficial effects to occur. The main disadvantage of these products is that they are expensive compared to non-fortified alternatives and statins. Note that NICE guidelines cannot recommend for patients to take these products for the primary or secondary prevention of CVD, as there is minimal evidence regarding the effectiveness of
Nutrition, October 2014
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CHOLESTEROL individual would need to take probiotics for and also which strains of bacteria have any beneficial effects (DiRienzo, 2014). Therefore, further clinical evidence is needed in this area before recommendations can be made. In addition, there have been reported incidences of probiotics causing systemic infection in immunocompromised individuals (Ooi et al, 2010). Moreover, certain strains of probiotics have shown antibiotic resistance and so the safety and dosage needs to be considered before widespread use is recommended.
Conclusion Randomised trials have found that if LDL cholesterol is reduced by 1.6 mmol/L, then after 2 years this can halve the risk of ischaemic heart disease (IHD) events (Law et al, 2003). This same study has found that statins can lower LDL cholesterol by 1.8 mmol/L, demonstrating they are an effective treatment. We need to understand how much phytostanols, sterols and probiotics can reduce LDL cholesterol by, in order to measure up their effectiveness compared to current medication as a natural alternative. Current literature is conflicting and does not suggest that these natural products have as significant an effect on lipid profiles, but could be used in addition to cholesterol-lowering medication, or for those who do not tolerate the medication or prefer to choose a more natural treatment. Further research in this area is required before probiotics can be suggested as a treatment as we do not know which specific strains and dosage
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© Lucie Carlier
The mechanism by which probiotics affect cholesterol is not well understood, although several theories have been suggested. A review suggested that the accepted theory is that probiotics inhibit intestinal cholesterol absorption and that it suppresses bile acid reabsorption (Zhuang et al, 2012). The theory of bile acid reabsorption having an effect has further been supported by DiRienzo (2014). There has been recent evidence that carnitine (a quaternary ammonium compound, derived from amino acids), found in red meat and dairy products, is also responsible for raising LDL cholesterol levels (Koeth et al, 2013). This is thought to be a hidden contributor to raising cholesterol levels, as for many decades it has been understood that it is the saturated fat in red meat that affects LDL. Early work in rodents by Koeth et al (2013) has shown that the breakdown of carnitine results in increased colonisation of bacteria in the gut and formation of trimethylamine N-oxide (TMAO) metabolite, which promotes cholesterol deposition (Koeth et al, 2013). This is possibly a method in which probiotics might help lower cholesterol levels as they could help to balance the gut flora and counter the actions of carnitine. Further evidence of this is needed in human studies and it is a growing area of interest. The evidence for the use of probiotics in lowering LDL cholesterol is conflicting, with some studies showing an improvement in lipid profiles and others showing insignificant effects. There is minimal evidence to show what dosage is required for any effect, the duration an
A healthy diet and lifestyle can help to manage lipid profiles
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CHOLESTEROL of probiotics is required. Another factor to consider is cost. These natural products could be purchased by the individual, rather than having a cholesterollowering medication prescribed, saving the NHS money at a time when medicines management savings projects are growing. Alongside any intervention, it is key that healthy eating recommendations and lifestyle changes are also implemented to help manage cholesterol levels. BJCN Anderson J, Gilliland S (1999) Effect of fermented milk (yoghurt) containing Lactobacillus acidophilus L1 on serum cholesterol in hypercholesterolemic humans. J Am Coll Nutr 18(1): 43–50 Bellosta S, Paoletti R, Corsini A (2004) Safety of statins focus on clinical pharmacokinetics and drug interactions. Circulation 109(23 Suppl 1): III50–7 Bertolami M, Faludi A, Batlouni M (1999) Evaluation of the effects of a new fermented milk product (Gaio) on primary hypercholesterolemia. Eur J Clin Nutr 53(2): 97–101 Birtcher K, Ballantyne C (2004) Measurement of cholesterol: a patient perspective. Circulation 110: 296–7 DiRienzo D (2014) Effect of probiotics on biomarkers of cardiovascular disease: implications for heart-healthy diets. Nutr Rev 72(1): 18–29. doi: 10.1111/nure.12084 Food and Agriculture Organization of the United Nations and World Health Organization (2001) Report on Joint FAO/ WHO expert consultation on evaluation of health and nutritional properties of probiotics in food including powder milk with live lactic acid bacteria. http://tinyurl.com/8bccc3r (accessed 24 September 2014) Goldenberg J, Ma S, Saxton J et al (2013) Probiotics for the prevention of Clostridium difficile-associated diarrhoea in adults and children. Cochrane Database Syst Rev 5: CD006095. doi: 10.1002/14651858.CD006095.pub3 Hasler C (2000) The changing face of functional foods. J Am Coll Nutr 19(5 Suppl): 499S–506S Hasler C, Bloch A, Thomson C, Enrione E, Manning C (2004) Position of the American Dietetic Association: Functional foods. J Am Diet Assoc, 104, 814-26 Hatakka K, Mutanen, M., Holma R, Saxelin M, Korpela R (2008) Lactobacillus rhamnosus LC705 together with Propionibacterium freudenreichii ssp shermanii JS Administered in capsules is ineffective in lowering serum lipids. J Am Coll Nutr 27(4): 441–7 Jones P, Raeini-Sarjaz M, Ntanios F, Vanstone C, Feng J, Parsons W (2000) Modulation of plasma lipid levels and cholesterol kinetics by phytosterol
versus phytostanol esters. J Lipid Res 41(5):697–705 Jones M, Martoni C, Parent M (2012) Cholesterol-lowering efficacy of a microencapsulated bile salt hydrolase-active Lactobacillus reuteri NCIMB 30242 yoghurt formulation in hypercholesterolaemic adults. Br J Nutr 107(10): 1505–13. doi: 10.1017/S0007114511004703 Katan M., Grundy S, Jones P et al (2003) Efficacy and safety of plant stanols and sterols in the management of blood cholesterol levels. Mayo Clin Proc 78(8): 965–78 KeiBling G, Schneider J, Jahreis G (2002) Long-term consumption of Fermented Dairy Products over 6 months increases HDL Cholesterol. Eur J Clin Nutr 56(9): 843–9 Kidambi S, Patel S (2008) Sitosterolaemia: pathophysiology, clinical presentation and laboratory diagnosis. J Clin Pathol 61(5): 588–94. doi: 10.1136/ jcp.2007.049775 Koeth R, Wang Z, Levison B (2013) Intestinal microbiota metabolism of l-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med 19(5): 576–85. doi: 10.1038/nm.3145 Law M., Wald N, Rudnicka A (2003) Quantifying effect of statins on low density lipoprotein cholesterol, ischaemic heart disease, and stroke: systemic review and meta-analysis. BMJ 326(7404): 1423 National Institute for Health and Care Excellence (2014) Lipid Modification: cardiovascular risk assessment and the modification of blood lipids for the primary and secondary prevention of cardiovascular disease. Guideline CG181. http://tinyurl.com/l8t9nez (accessed 24 September 2014) Office of National Statisitcs (2014) Cancer. http://tinyurl.com/k3tyexn (accessed 24 September 2014) Ooi L, Liong M. (2010) Cholesterol lowering effects of Probiotics and Prebiotics: A Review of in Vivo and in Vitro Findings. Int J Mol Sci 11(6): 2499–522. doi: 10.3390/ijms11062499 Townsend N, Wickramasinghe K, Bhatnagar P, Smolina (2012) Coronary heart disease statistics: A compendium of health statistics - 2012 edition. http:// tinyurl.com/mzdd56t (accessed 24 September 2014) Unal B, Critchley J, Capewell S (2004) Explaining the Decline in Coronary Heart Disease Mortality between 1981 and 2000. Circulation 109(9): 1101–7 Vaughan C, Murphy M and Buckley B (1996) Statins do more than just lower cholesterol. Lancet 348(9034):1079–82 Webb G (2006) Dietary Supplements and Functional Foods. 1st edn. Blackwell Publishing, Oxford: 207–11 World Health Organization (2013) Cardiovascular disease; Fact sheet No 317, http://tinyurl.com/br89ujf (accessed 24 September 2014) Zhuang G, Liu X, Zhang Q, Tian F et al (2012) Research advances with regards to clinical outcomes and potential mechanisms of the cholesterol-lowering effects of probiotics. Clinical Lipidology 7(5): 501–7. doi:10.2217/clp.12.40
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