What Causes Parkinson’s Disease? Understanding the Risk Factors, Genetics, and Brain Changes

What Is Parkinson’s Disease Caused By?
Parkinson’s disease (PD) is a complex neurological condition that affects movement, balance, and many non-motor functions. While millions of people worldwide live with Parkinson’s, one of the most common questions after diagnosis is also the hardest to answer: What caused this? The truth is, Parkinson’s disease rarely has a single cause. Instead, it develops due to a combination of biological, genetic, and environmental factors.

Here’s what science knows so far — and why understanding the cause can empower better care, earlier detection, and stronger support.  Keep reading to learn more.

1. The Brain Changes Behind Parkinson’s Disease:
Parkinson’s disease occurs when specialized nerve cells (neurons) in a part of the brain called the substantia nigra begin to deteriorate. These neurons produce dopamine, a chemical messenger essential for smooth, coordinated movement.

As dopamine levels drop, people may experience symptoms such as:

• Tremors
• Slowness of movement
• Muscle stiffness
• Balance issues

Another hallmark of Parkinson’s is the presence of Lewy bodies, abnormal protein clumps made largely of alpha-synuclein. These protein accumulations interfere with normal brain cell function and are believed to play a key role in disease progression.

2. Genetics: Is Parkinson’s Hereditary?
For most people, Parkinson’s is not directly inherited. However, genetics can increase susceptibility. Researchers have identified several gene mutations linked to Parkinson’s disease, including LRRK2, PARK7, PINK1, and SNCA.
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Genetic Parkinson’s accounts for only about 10–15% of cases, but having a close family member with PD may slightly raise the risk. Even then, genes usually interact with other factors rather than acting alone.

3. Environmental and Lifestyle Risk Factors:
Environmental exposure appears to be a significant contributor for many individuals. Factors associated with increased Parkinson’s risk include:

• Long-term exposure to pesticides or herbicides
• Living in rural or agricultural areas
• Well water contamination
• Head injuries or repeated trauma

Researchers believe these exposures may trigger oxidative stress and inflammation in the brain, accelerating neuron damage over time.

4. Age and Other Contributing Factors:
Age is the largest risk factor for Parkinson’s disease. Most diagnoses occur after age 60, though early-onset Parkinson’s can occur. Men are also slightly more likely than women to develop PD.
Importantly, Parkinson’s develops slowly, often beginning years before symptoms become noticeable. This is why early awareness and monitoring are so valuable.

Why Support Matters:
A diagnosis of any form of Parkinson’s can feel overwhelming. But with the right support and resources, individuals can maintain independence, quality of life, and emotional well-being.

For resources, referrals, and support in navigating Parkinson’s and related conditions, contact the Parkinson’s Association of Southwest Florida (PASWFL) at www.paswfl.org or call 239-417-3465.
For over 25 years, PASWFL has provided free, high-quality services to individuals and families touched by Parkinson’s disease in Southwest Florida. Their goal is simple: help people live well with PD, regardless of where they are in their journey.
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Each week, PASWFL offers more than 25 free programs, including:

• Wellness and fitness classes
• Speech exercise classes
• Educational seminars
• Support for care partners
• Support groups

There are no fees to become a member, and PASWFL welcomes anyone touched by PD.

Take the First Step Toward Living Well:
If you suspect early Parkinson’s or have been recently diagnosed, you don’t have to face it alone.
👉 Sign up for the PASWFL newsletter: https://parkinsonassociationswfl.org/signup-enews.html
👉 Become a free, confidential member: https://parkinsonassociationswfl.org/signup.html
To learn more, visit www.paswfl.org and discover the power of support, education, and community.