A million Americans have Parkinson’s disease, and that number is expected to increase to 1.2 million by 2030. Most of those afflicted are between 75 and 85, but 4% are under 50.
The cause is still mostly unknown, but 10-15% is likely genetic and much of the rest may be due to environmental factors like exposure to pesticides, herbicides, heavy metals, detergents, and solvents. There is also a moderate link with head trauma.
A protein called alpha synuclein helps with the transmission of nerve impulses between nerve cells. Sometimes this protein becomes misshapen and can accumulate in clumps called Lewy bodies within a nerve cell. In the midbrain, they can destroy dopamine production, leading to Parkinson’s disease. If they occur more in the brain’s cortex, Lewy body dementia is often the result. But 40 to 80% of Parkinson’s patients eventually develop dementia.
A new study of almost 10,000 Parkinsonian patients that had undergone upper endoscopy and followed up after an average of 15 years showed that damage to the wall of the gut may be another potential cause of the disease. Controlling for potential confounding factors, having erosions or ulcers in the lower stomach or duodenum may increase the risk of Parkinson’s by about 75%.
GI bacteria that erode the gut wall are known to misshape proteins like alpha synuclein. Studies in mice show that when this protein is injected into the pylorus or duodenal mucosa, it is transported to the midbrain via the vagus nerve.
Many simple health tips may have bigger implications to prevent Parkinson’s disease than we imagine. Diets high in processed or ultra-processed foods are inherently low in the fiber that gut bacteria feed on, encouraging them toward attacking the gut wall and promoting inflammation.
A specific bacterium called H. pylori is particularly associated with ulcers of the stomach and duodenum. A simple blood test for antibodies can identify exposure to this bacterium. A two-drug regimen taken for a couple of weeks can eradicate it. A breath test can confirm its continued absence.
Our gut microbiomes are complex, and specific dietary recommendations to best support them are premature, but it is probably a good idea to give these organisms something to eat.
A metanalysis shows that every 10 grams of dietary fiber confers a 10% reduction in all-cause mortality. Frequently “seeding” our guts with a combination of healthy bacteria like that from a low-fat active culture dairy source can also help. A longitudinal study of women shows that regular yogurt consumption can cut all-cause mortality by 17%.
Stress can more than double our risk for GI ulcers, so even though we may know it, it’s good to be reminded not to sweat the small stuff, and it is mostly small stuff.
William Culbert is a retired physician. He lives in Oak Ridge.
