With a vast array of novel researches performed on probiotics, scientists have been able to reveal the influence of gut bacteria on cardiac health. These beneficial bacteria help control the factors that have a negative impact on the heart, and therefore, provide a ground to optimize the cardiac health.
Probiotics can help improve the following risk factors for heart disease:
1. Formation of fatty plaques
The cholesterol that we consume in our diet can combine with fat, calcium, and other substances in our blood to generate plaques or fatty deposits. These plaques that clog arteries (primarily of the heart) form as a result of a series of inflammatory steps. One of the reasons that cardiologists recommend probiotics for heart health is the suppression of these inflammatory processes that trigger the formation of fatty deposits in your arteries.
A 2010 study showed that probiotic-containing Bifidobacteria exerts anti-inflammatory effects via decreasing the number of white blood cells being propelled to a damaged artery and, thus, lessening the inflammation and the chances of cholesterol buildup in that area. 
Moreover, probiotics, in particular, Lactobacillus reuteri NCIMB 30242 has been proven to cut the bad cholesterol levels by about 12%.  This further resists the accumulation of fatty plaques in the arteries. This probiotic, in essence, can eat up cholesterol owing to its distinctive bile salt hydrolase activity.
2. Blood pressure
Hypertension is estimated to affect several billion people worldwide and is a major but modifiable risk factor for cardiac disease. Luckily, recent studies show that certain probiotics, primarily lactobacilli can lower the blood pressure through a variety of mechanisms. One such mechanism is the relaxation (or widening) of blood vessels via blocking the angiotensin-converting enzyme (ACE) activity. This enzyme narrows the blood vessels, raising the pressure of the flowing blood on the walls of the arteries, which defines hypertension. By suppressing the ACE activity, probiotic bacteria perform the same action as that of some of the commonly used blood pressure medications like Zestril and Monopril. 
3. Vitamin D levels
The vitamin D acknowledged for bone health is also crucial for cardiovascular health. Insufficient vitamin D levels can narrow the blood vessels and impair the function of filtration by the kidneys, both of which tend to raise the blood pressure.  According to a Canadian study, regular supplementation of the probiotic L. reuteri NCIMB 30242 boosted vitamin D levels by more than 25%, which is a notable increase. Hence, probiotics can be regarded as cardioprotective agents. 
Obese individuals are at high risk for cardiac disease sooner or later. Being a modifiable factor, obesity can be addressed via lifestyle modifications. One such modification is the supplementation of probiotics. These can help you lose weight, thereby reducing your odds of developing heart problems. 
5. Blood sugar levels
Diabetes is a known risk factor for heart disease. Probiotics can help tame the rising blood sugar levels, probably by driving insulin release from the pancreas. Insulin production after meals lowers the blood sugar levels. Also known to occur in response to probiotic supplementation is the release of another hormone called incretin. Incretin stimulates insulin release and therefore, lowers the blood sugar levels.
Written by Dr. Rasheed Huma
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- Jones ML, Martoni CJ, Prakash S. Cholesterol lowering and inhibition of sterol absorption by Lactobacillus reuteri NCIMB 30242: a randomized controlled trial. Eur J Clin Nutr. 2012;66(11):1234-41. doi: 10.1038/ejcn.2012.126.
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