We know that what we eat and drink has a significant impact on our health, and a new study has found another connection between drinking coffee and being less likely to develop Parkinson's disease.

Looking at data collected on 184,024 individuals across an average of 13 years, the international team of researchers behind the study found that coffee consumers had a lower risk of getting Parkinson's than those that didn't drink coffee at all.

Further analysis of a sample of hundreds of people with Parkinson's measured levels of the primary metabolites of caffeine, paraxanthine, and theophylline, in the blood – finding that they had an inverse association with the risk of developing Parkinson's.

"This study demonstrated an inverse association of caffeinated coffee consumption with the risk of Parkinson's disease in one of the largest longitudinal cohorts worldwide with more than 20 years of follow-up," write the researchers in their published paper.

This isn't the first study to find a link between coffee and Parkinson's, but it goes further than previous research in the way it looks at biomarkers of caffeine intake years ahead of Parkinson's disease being diagnosed.

The top 25 percent of coffee drinkers were found to be 40 percent less likely to develop Parkinson's, compared to those who didn't drink coffee at all. Across all coffee consumers in the study, the risk reduction measured varied between approximately 5 to 63 percent, depending on the country.

While the association still held when factors such as smoking and drinking were accounted for, it's still not enough to prove direct cause and effect. However, there does seem to be something about caffeine and its ingredients that is protecting people's brains.

Based on previous research, it's thought that the way caffeine keeps dopamine flowing in the brain might be the reason for these effects. Parkinson's in the brain is characterized by a reduction in dopamine, due to a loss of nerve cells in what's called the substantia nigra.

"These neuroprotective effects align with our findings, which revealed an inverse association between caffeine, paraxanthine, and theophylline and the incidence of Parkinson's disease," write the researchers.

Considering the way that caffeine hits our neurons, it's perhaps not surprising that there appears to be a relationship with neurodegenerative diseases. However, as we're still not sure how exactly Parkinson's gets started in the brain, it's difficult to be sure.

The important work of figuring out what triggers Parkinson's, what might affect our risk of getting the disease, and how it might be stopped, goes on. In the US alone, nearly a million people are living with the disease, which leads to worsening problems with tremors, normal movement, balance, and limb stiffness.

"Coffee is the most widely consumed psychoactive beverage in the world," write the researchers.

"Unraveling the biological action of caffeine on Parkinson's disease not only carries important public health implications but also enhances our understanding of Parkinson's disease etiology and fosters potential prevention strategies."

The research has been published in Neurology.