Heart disease is the most common cause of death worldwide.
Therefore, it is important to look after your heart, especially as you get older.
There are many foods that benefit heart health. Recent studies have shown that probiotics may also be beneficial.
This article will discuss how probiotics may benefit heart health.
What Are Probiotics?
Probiotics are live microbes that, when eaten, provide certain health benefits (1).
Probiotics are usually bacteria such as Lactobacilli and Bifidobacteria. However, not all are the same, and they can have different effects on your body.
In fact, your intestines contain trillions of microbes, mainly bacteria, that affect your health in many ways (2).
For example, your gut bacteria control how much energy you digest from certain foods. Therefore, they play an important role in your weight (3).
Your gut bacteria can also affect your blood sugar, brain health and heart health by reducing cholesterol levels, blood pressure and inflammation (4, 5, 6).
Probiotics can help restore healthy gut bacteria, which may improve your heart health.
Probiotics May Lower Your Cholesterol
A number of large studies have shown that certain probiotics may be able to lower blood cholesterol, particularly in people with high cholesterol levels.
One of these, a review of 15 studies, specifically examined the effects of Lactobacilli.
There are two main types of cholesterol: high-density lipoprotein (HDL) cholesterol, which is generally seen as â€œgoodâ€ cholesterol, and low-density lipoprotein (LDL) cholesterol, which is generally viewed as â€œbadâ€ cholesterol.
This review found that, on average, Lactobacillus probiotics significantly reduced both total cholesterol and â€œbadâ€ LDL cholesterol levels (7).
The review also found that two types of Lactobacillus probiotics, L. plantarum and L. reuteri, were particularly effective in reducing cholesterol levels.
In one study of 127 people with high cholesterol, taking L. reuteri for 9 weeks significantly lowered total cholesterol by 9% and â€œbadâ€ LDL cholesterol by 12% (8).
A larger meta-analysis combining the results of 32 other studies also found a significant beneficial effect in reducing cholesterol (9).
In this study, L. plantarum, VSL#3, L. acidophilus and B. lactis were particularly effective.
Probiotics were also more effective when taken by people with higher cholesterol, when taken for a longer period of time and when taken in capsule form.
There are a number of ways that probiotics may reduce cholesterol (10).
They can bind with cholesterol in the intestines to stop it from being absorbed. They also help produce certain bile acids, which help metabolize fat and cholesterol in your body.
Certain probiotics can also produce short-chain fatty acids, which are compounds that can help prevent cholesterol from being formed by the liver.
They May Also Reduce Blood Pressure
High blood pressure is another risk factor for heart disease, and it may be lowered by certain probiotics.
One study of 36 smokers found that taking Lactobacilli plantarum for 6 weeks significantly reduced blood pressure (11).
However, not all probiotics are effective for improving heart health.
A separate study of 156 people with high blood pressure found that two types of probiotics, Lactobacilli and Bifidobacteria, had no beneficial effect on blood pressure when given in capsules or yogurt (12).
However, other large reviews combining the results from other studies have found an overall beneficial effect of certain probiotics on blood pressure.
One of these large studies found a reduction in blood pressure, especially under the following conditions (13):
- When blood pressure was high originally
- When multiple types of probiotics were taken at the same time
- When the probiotics were taken for more than 8 weeks
- When the dose was high
A larger study that combined the results of 14 other studies, including 702 people in total, found that probiotic fermented milk also significantly reduced blood pressure in people with high blood pressure (14).
Probiotics Could Also Lower Triglycerides
Probiotics may also help reduce blood triglycerides, which are types of blood fat that can contribute to heart disease when their levels are too high.
A study of 92 people who had high blood triglycerides found that taking two probiotics, Lactobacillus curvatus and Lactobacillus plantarum, for 12 weeks significantly reduced blood triglycerides (15).
However, larger studies that combine the results of many other studies have found that probiotics may not affect triglyceride levels.
Two of these large meta-analyses, one combining 13 studies and the other combining 27 studies, found no significant beneficial effect of probiotics on blood triglycerides (16, 17).
Overall, more human studies are needed before drawing conclusions on whether or not probiotics can help reduce blood triglycerides.
Probiotics May Reduce Inflammation
Inflammation occurs when your body switches on your immune system in order to fight an infection or heal a wound.
However, this can also happen as a result of a bad diet, smoking or an unhealthy lifestyle, and if it happens over a long time it can contribute to heart disease.
One study of 127 people with high cholesterol levels found that taking a Lactobacillus reuteri probiotic for 9 weeks significantly reduced the inflammatory chemicals C-reactive protein (CRP) and fibrinogen (18).
Fibrinogen is a chemical that helps blood to clot, but it may contribute to plaques in the arteries in heart disease. CRP is a chemical made by the liver that is involved with inflammation.
Another study of 30 men with high cholesterol levels found that taking a food supplement containing fruit, fermented oatmeal and the probiotic Lactobacillus plantarum for 6 weeks also significantly reduced fibrinogen (19).
The Bottom Line
Probiotics are live microbes that have certain health benefits. There is good evidence that certain probiotics can reduce cholesterol, blood pressure and inflammation.
However, most of the study participants already had high blood pressure or cholesterol. Furthermore, not all probiotics are the same and only some may benefit heart health.
Overall, if you have high cholesterol or blood pressure, certain probiotics may be useful in addition to other medicines, diet and lifestyle changes.