There are hundreds of recent studies showing that the microbes (bacteria, fungi, and viruses) living in your gut impact your health. The right microbes benefit you, the bad ones cause you harm.

You have trillions of diverse microbes (with 10 times more DNA than the human body) living in your intestines. The proper microbes metabolize toxins and drugs, lower inflammation, help you absorb nutrients, and suppress appetite.

Little more than a decade ago, investigators proposed that the gut microbiome might be contributing to obesity. Since then, the microbiome has been linked to many other health issues, including depression, ADHD, memory loss, menopause symptoms, and most recently heart disease.

How does the microbiome impact risk factors for heart disease?

Risk factors for arterial plaque growth and heart disease include: obesity, elevated blood sugar levels, cholesterol profiles, inflammation, and blood pressure.

Obesity

It is not only the calories that people ingest that affect weight: more specifically it is the calories people absorb from the gut. By increasing or decreasing the amounts of digestible sources of energy, particularly monosaccharides and short-chain fatty acids, gut bacteria affect the number of calories that humans absorb.

Bad bacteria in the gut produce a chemical compound called proprionic acid. Proprionic acid will travel through the blood to the brain, and induce cravings for sugar and refined carbs, which in turn feeds the bad bacteria. Adding more beneficial gut microbes will block proprionic acid production.

Consider a study where lean mice were fed feces from human twins. Feces from the fat twins caused lean mice to become fat, and feces from the lean twins allowed mice to remain lean. When the fat and lean mice were housed together, and ate each other’s feces, the obese mice became lean and their gut flora came to resemble the flora of the lean mice (and the lean human twins).

We have recently discovered that with a fecal transplant (stool delivered from one person to another via an enema), people who are overweight will lose weight and become lean—FYI fecal transplants are not yet approved or available in the USA for weight loss. But this should give you an incentive to protect and promote your gut microbiome.

Elevated blood sugar levels

People with the wrong microbiome microbes will produce relatively more acetate and less butyrate, which increases insulin resistance and blood sugar levels.

In rodents, studies have shown that giving the right probiotic sources will improve insulin sensitivity and blood sugar control.

Cholesterol profiles

Cholesterol is converted to bile acids to help with fat digestion—if you are able to increase bile acid production, you lower cholesterol levels.

Since your gut microbiome will modify how many bile acids are produced, if you have the right gut microbes, your gut microbiome can lower your cholesterol levels.

Blood Pressure

Several studies have found that particular members of the right Lactobacillus species in the gut lower blood pressure levels.

Inflammation

Many forms of gut bacteria and fungi will trigger low-grade inflammation in the gut, allowing entry of bacteria and bacterial products into the circulation, and result in high levels of chronic systemic inflammation. Elevated inflammation levels are strongly associated with growth of arterial plaque and a greater risk for heart attacks and strokes. The right gut microbes have been shown to lower systemic inflammation levels.

Summary

Gut microbes influence and reduce multiple risk factors for heart disease (elevated blood sugar levels, obesity, cholesterol, blood pressure, and inflammation) and thus have the potential to help prevent the #1 killer for women and men.

Be sure to support your microbiome.

  • Eat an abundance of fiber (vegetables, fruits, beans, and nuts). Without proper fiber intake, your gut microbiome microbes will starve
  • Avoid antibiotic use unless absolutely required for medical emergencies
  • Consume probiotic foods or supplements daily (sauerkraut, miso, yogurt, kefir)
  • Avoid toxins that hurt your microbiome, such as Splenda (an artificial sweetener)

I wish you the best of health!

Steven Masley, MD, FAHA, FACN, FAAFP, CNS

 

References

  1. Komaroff  AL.  The microbiome and risk for obesity and diabetes. JAMA. 2017;317(4):355-356.
  2. Sayin  SI, Wahlström  A, Felin  J,  et al.  Gut microbiota regulates bile acid metabolism by reducing the levels of tauro-beta-muricholic acid, a naturally occurring FXR antagonist. Cell Metab. 2013;17(2):225-235.
  3. Pluznick  JL, Protzko  RJ, Gevorgyan  H,  et al.  Olfactory receptor responding to gut microbiota-derived signals plays a role in renin secretion and blood pressure regulation. Proc Natl Acad Sci U S A. 2013;110(11):4410-4415.
  4. Wilck  N, Matus  MG, Kearney  SM,  et al.  Salt-responsive gut commensal modulates TH17 axis and disease. Nature. 2017;551(7682):585-589.
  5. Tang  WH, Wang  Z, Levison  BS,  et al.  Intestinal microbial metabolism of phosphatidylcholine and cardiovascular risk. N Engl J Med. 2013;368(17):1575-1584.
  6. Li  DY, Tang  WHW.  Gut microbiota and atherosclerosis. Curr Atheroscler Rep. 2017;19(10):39.
  7. Heianza  Y, Ma  W, Manson  JE, Rexrode  KM, Qi  L.  Gut microbiota metabolites and risk of major adverse cardiovascular disease events and death: a systematic review and meta-analysis of prospective studies. J Am Heart Assoc. 2017;6(7):e004947.
  8. Wang  Z, Roberts  AB, Buffa  JA,  et al.  Non-lethal inhibition of gut microbial trimethylamine production for the treatment of atherosclerosis. Cell. 2015;163(7):1585-1595.
  9. Loscalzo  J.  Gut microbiota, the genome, and diet in atherogenesis. N Engl J Med. 2013;368(17):1647-1649.PubMedGoogle ScholarCrossref
  10. Boorstin  DJ. The Discoverers. New York, NY: Random House; 1983:330-331.