One in three deaths in the U.S. is due to heart disease. Two big risk factors for heart disease are high LDL cholesterol and inflammation—and both are modifiable by lifestyle changes. One of the best clinically tested lifestyle changes includes supplementing with L. reuteri NCIMB 30242 (LRC) probiotics. What does the evidence say about using LRC vs. other probiotic strains for heart health and cholesterol?
Disclaimer: This post is for informational purposes only. Please discuss your health concerns with your care provider and consult them before taking any supplements to avoid disease and drug interactions.
- Scientists recognize gut microbial imbalance as a possible contributor to high LDL cholesterol, low HDL cholesterol, and inflammation—major risk factors for heart disease (Anthony & Leon, 2018)
- Several probiotic strains have been clinically researched for supporting normal cholesterol levels and markers of heart health. Among them, the scientific evidence is most in favor of L. reuteri NCIMB 30242, the strain in Microbiome Plus probiotic supplements (DiRienzo, 2014)
- L. reuteri NCIMB 30242 supports already normal levels of LDL cholesterol, total cholesterol, inflammatory markers (C-reactive protein and apolipoprotein B-100), fibrinogen, and plant sterols—factors that promote cardiovascular health (Jones et al., 2011, Jones et al., 2012)
- Other probiotic strains that may also support heart health and cholesterol based on limited research include: Lactobacillus plantarum CECT 7527, Lactobacillus plantarum CECT 7528, Lactobacillus plantarum CECT 7529, Lactobacillus plantarum ECGC 13110402, Lactobacillus bulgaricus, Lactobacillus sporogenes, and Bifidobacterium lactis HN019 (Fuentes et al., 2013; Bernini et al., 2018; Costabile et al., 2017; Khare & Gaur, 2020)
Which probiotics are best for cholesterol?
Total cholesterol as an unreliable marker of heart disease risk
A commonly cited 2018 review looked at the effects of various probiotic strains on total cholesterol levels. They concluded that probiotics in general lower total cholesterol better than the placebo, based on 32 clinical trials including almost 2k patients (Wang et al., 2018).
The authors discovered that Lactobacillus acidophilus, Bifidobacterium lactis, and Lactobacillus plantarum were the most commonly used probiotic strains for lowering total cholesterol levels. Yet, strong clinical evidence to support their effectiveness was lacking.
Based on the authors’ calculations, L. reuteri NCIMB 30242—the probiotic strain in Microbiome Plus supplements also known as LRC—lowered total cholesterol by about 4.4% when used in a yogurt formulation.
The original study reports that L. reuteri NCIMB 30242 lowered total cholesterol by 4.81%. This study was followed up by another study that found a 9.14% reduction with L. reuteri NCIMB 30242 capsules. The second study was not included in the review, which questions its scientific comprehensiveness (Jones et al., 2012; Jones et al., 2012).
What else is problematic about the 2018 review?
The most important flaw is that this analysis looked only at total cholesterol. This oversimplifies the heart disease risk. The impact of total cholesterol on heart disease risk is unclear and controversial, so let’s see what’s a better marker (Wang et al., 2018).
LDL cholesterol as a better marker
High LDL or “bad” cholesterol is a known risk factor for heart disease. Elevated levels of LDL cholesterol can clog arteries and disrupt blood flow, potentially causing heart attacks and stroke. Therefore, probiotic strains that show the potential to lower LDL cholesterol are more clinically valuable than strains that impact total cholesterol only (Gibbing et al., 2019).
A meta-analysis of 30 trials (including one Lactobacillus reuteri NCIMB 30242 trial) reported that probiotics in general lower LDL by only ~4% (Cho & Kim, 2015)
Similarly, a meta-analysis of 13 smaller probiotic clinical studies reported a mean reduction of LDL cholesterol by only ~3%. Yet, none included L. reuteri strains (Guo et al., 2011).
Lactobacillus reuteri and Lactobacillus plantarum seem to significantly reduce both total and LDL cholesterol, based on a focused analysis of 15 trials of Lactobacilli strains including close to 1k participants (Wu et al., 2017).
Scientists involved in L. reuteri NCIMB 30242 research believe that this strain has a stronger effect on LDL cholesterol and other heart-healthy factors than other probiotics that are currently being used. However, more clinical research is needed to confirm this (Jones et al., 2012)
Adding plant sterol levels to the equation
Limited evidence suggests that Lactobacillus reuteri NCIMB 30242 may support blood sterol levels already in the normal range. In the clinical trial of 127 people, Lactobacillus reuteri NCIMB 30242 decreased levels of several plant sterols in the blood (campesterol by 41.5%, sitosterol by 34.2%, and stigmasterol by 40.7%) (Jones et al., 2012).
Normal blood sterol levels contribute to heart and blood vessel health. Scientists are just beginning to explore the potential dangers of high sterol levels.
People with a rare genetic disorder sitosterolemia have very high plant sterols, fatty growths under the skin, and heart complications. Sterol levels above the normal range may disrupt red blood cells, platelets, blood clotting, and adrenal and ovarian health (Patel, 2019; Mushtaq et al., 2007).
Implications for cholesterol hyperabsorbersAside from being a health marker, blood sterol levels reflect cholesterol absorption in the body. This can help your doctor determine whether you’re a cholesterol hyperabsorber. About 25% of people are hyperabsorbers, which means that they absorb too much cholesterol in the gut (Lütjohann et al., 2019).
Based on limited research, Microbiome’s Lactobacillus Reuteri NCIMB 30242 may be a good supplement choice for supporting cholesterol balance in hyperabsorbers (Jones et al., 2012).
Probiotics for Heart Health
Are probiotics good for heart health?
Not all probiotics are good for heart health. The benefits of probiotics are often specific to a certain strain (Lactobacillus reuteri NCIMB 30242). Other times, the benefits may apply to the whole probiotic species (Lactobacillus reuteri/Limosilactobacillus reuteri) or genus (Lactobacilli).
Out of various Lactobacillus reuteri strains, only Lactobacillus reuteri NCIMB 30242 has been clinically researched for supporting healthy cholesterol levels and other markers of heart health.
Proponents claim that the effects of probiotics on total and LDL cholesterol are enough to classify them as heart-healthy.
However, heart health is a lot more complex than total and LDL cholesterol levels. Other markers that increase the risk of heart disease include inflammation, increased blood clotting, low HDL cholesterol, and high levels of serum triacylglycerol and triglyceride-rich lipoproteins. Genetic factors, lifestyle, age, and other chronic diseases also play in (DiRienzo, 2014).
Adopting a healthy lifestyle helps reduce some markers of heart disease risk. General steps you can take include maintaining a healthy body weight, engaging in regular physical activity, consuming a nutritious diet, reducing trans fat intake, and avoiding tobacco. More specific and evidence-based approaches include dietary supplements like targeted probiotic strains.
In the next section, we’ll zoom in on markers of chronic inflammation, blood clotting, and blood circulation that have the potential to be modified by probiotics.
What is the best probiotic for heart health?
According to researchers, therapeutic lifestyle changes (TLCs) for heart disease can include the regular consumption of specific clinically tested foods or supplements, such as probiotics and fiber (DiRienzo, 2014).
One scientific review concluded that L. reuteri NCIMB 30242 probiotics best meet TLC heart-healthy requirements since they (DiRienzo, 2014):
- Reduce LDL and total cholesterol similar to existing dietary options
- Improve other heart disease risk factors, such as inflammatory biomarkers, and
- Have "generally recognized as safe" (GRAS) status.
In one study, Lactobacillus reuteri NCIMB 30242 yogurt taken twice a day for 6 weeks reduced LDL by ~9%, total cholesterol by ~5%, and non-HDL cholesterol by 6% compared to placebo in 114 adults with high cholesterol (Jones et al., 2012).
In another study, L. reuteri NCIMB 30242 capsules reduced LDL cholesterol by ~11.6%, total cholesterol by ~9%, and non-HDL cholesterol by ~11% compared to placebo in 127 people over 9 weeks. Supplementation also improved two other markers of heart health: the LDL-C/HDL-C ratio (by ~13%) and ApoB-100 (by ~8%) (Jones et al., 2012).
- Lactobacillus plantarum CECT 7527
- Lactobacillus plantarum CECT 7528
- Lactobacillus plantarum CECT 7529
- Lactobacillus plantarum ECGC 13110402 (may work similar to L. reuteri NCIMB 30242 but is less researched)
- Lactobacillus bulgaricus
- Lactobacillus sporogenes
- Bifidobacterium lactis HN019
More clinical research on the efficacy and safety of each of these strains is needed before they can be recommended to heart disease patients.
Probiotics cardiologist warning
You may have heard about the “probiotics cardiologist warning” in the popular press. Why do cardiologists warn against probiotics in some cases?
In serious and rare cases, heart disease and certain medications used to manage heart disease may weaken the immune system causing immunocompromization.
If you suffer from weak immune system function, please consult a specialist before taking any supplements.
According to studies, probiotics containing live microorganisms should be used with caution in immunocompromised patients because they may cause infection or pathologic colonization (Anthony & Leon, 2018).
In one case, a patient with an advanced and severe heart condition (bicuspid aortic valve stenosis) developed heart inflammation or endocarditis from L. paracasei supplementation (Anthony et al., 1996).
On the other hand, one added benefit of L. reuteri NCIMB 30242 is that it supports immunity. It’s the only probiotic reported to increase vitamin D levels in clinical studies. Therefore, vitamin D and probiotics co-supplementation may be beneficial (Jones et al., 2013).
The existing evidence suggests that specific strains of Bifidobacterium lactis, Lactobacillus plantarum, Lactobacillus bulgaricus, Lactobacillus sporogenes, and Lactobacillus reuteri may support heart health and cholesterol. Of them, solid clinical evidence backs up the use of L. reuteri NCIMB 30242 (LRC), the strain in Microbiome Plus probiotics.