Parkinson's disease affects an estimated 4% of people over the age of 50 - a number that exceeds 10 million people across the globe each year. It is the second most common neurodegenerative disorder - behind only Alzheimer's disease in its incidence.
There is an abundance of research about what works to help manage symptoms and slow progression in PD, from pharmaceuticals to the foods we eat. This article will review a Functional Medicine Approach to Parkinson's Disease, including nutrition, lifestyle interventions, pharmaceuticals, physical medicine, and more.
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Signs & Symptoms of Parkinson's Disease
Parkinson's disease is a neurological disorder characterized by tremors, slowed movements, changes in writing and speech, and (at times) cognitive impairment. Parkinson's used to be thought of primarily as a motor disorder (disorder affecting the muscles and nervous system), but it is now known that it affects every system in the body.
- Tremor (shaking in a limb at rest or with movement)
- Bradykinesia and slowed movements
- Muscle rigidity
- Stooped posture and impaired balance (trouble with walking and more)
- Autonomic dysfunction (impaired body temperature control, salivation, etc.)
- Sleep issues
- Changes in voice (softer voice and difficulty speaking)
- Changes in writing (micrographia)
- Gastrointestinal problems like constipation and trouble with swallowing
- Urinary issues
- Loss of smell (anosmia)
- Mood issues like depression and anxiety
Symptoms of Parkinson's can develop gradually. They often begin on one side of the body, and some symptoms (like tremors) can temporarily worsen with stress. The diagnosis of Parkinson's disease is generally made by a neurologist after physical examination and testing. It is sometimes confirmed by testing to see if PD symptoms improve after L-DOPA administration.
Possible Causes of Parkinson's Disease
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Parkinson's disease is generally defined as the loss of dopamine-producing neurons in a particular part of the brain called the substantia nigra. Additionally, it involves the accumulation of alpha-synuclein (or Lewy bodies) in the cytoplasm of other neurons. Our understanding of the pathophysiology of Parkinson's is still evolving, but research has shown that a variety of factors - including genetics, oxidative stress, inflammation, viral infections, dysbiosis, microglial activation, environmental exposure, and more - can play a role in the development of Parkinsonian symptoms.
Toxic Metals
Toxic metal exposures can cause nervous system symptoms that look very much like Parkinson's disease. The most famous heavy metal linked to Parkinson's is manganese. High levels of manganese can cause a disorder called manganism which mimics PD closely and includes tremors, bradykinesia, cognitive impairment, and more.
Environmental Exposure
Certain pesticides, herbicides, fungicides, rodenticides, and fumigant exposures are linked with the development of Parkinson's disease. This is because many of these chemicals are neurotoxic and - in large amounts - can damage cellular mitochondria, the brain, and other tissues. While Parkinson's disease existed long before the invention of these chemicals, we know that exposure to them makes a person more likely to develop PD today. The most famous example of pesticide-related Parksinsons' is Paraquat, a pesticide first introduced in the 1960s in the United States. Some studies showed that Paraquat caused a loss of up to 30% of the dopaminergic neurons in the substantia nigra in mice, and it is shown in the literature to be related to several cases of the development of Parkinson's symptoms after exposure.
Viral Infections
Viral infections like influenza, Epstein-Barr virus (EBV), and herpes viruses have also been associated with PD development. It's thought that viral infections may trigger immune system changes that lead to inflammation and neurodegeneration.
Genetics
Many genetic factors are thought to be associated with an increased chance of developing PD. Much of the research in PD is devoted to understanding the genetic underpinnings of Parkinson's disease due to its perceived heritability - or likelihood of occurring in families.
Possible Causes of Increased Severity of Symptoms of Parkinson's Disease
Hormone Imbalances
Males are about 1.5 times as likely to experience Parkinson's disease as women.
Abnormalities in hormones like estrogen, progesterone, testosterone, DHEA, and neurohormones like serotonin, dopamine, and norepinephrine are linked with Parkinson's disease symptoms.
Evidence suggests that DHEA - an adrenal hormone that is also the precursor to testosterone and estrogen - is involved in the muscle wasting process in Parkinson's. Studies have demonstrated that supplemental DHEA can help reverse some muscle atrophy in the lower limbs of mammals with Parkinson's.
Thyroid Hormone
People with Parkinson's are more likely to have a thyroid disorder than those without PD? Research is still evolving as to why the link exists. Many scientists theorize that it may have something to do with dopamine production and thyroid hormone sharing many of the same biochemical precursors and are linked by certain enzymatic and hormonal pathways processes.
Thyroid hormone abnormalities are correlated with subtypes of Parkinson's disease and can make symptoms worse if they are not controlled.
Oxidative Stress
Dopaminergic neurons in the substantia nigra are particularly vulnerable to oxidative stress. An emerging body of research connects mitochondrial dysfunction, oxidative stress, DNA changes, and alterations in cell signaling with the progression of Parkinson's disease.
Along with this research is a renewed focus on preventive measures for neurodegenerative disorders to maximize cellular health and antioxidant capacity in the body. These strategies are called "neuroprotective" and involve lifestyle, nutrition, and other changes discussed below.
Micronutrient Deficiencies
Specific deficiencies of vitamins like cobalamin (B12), folate, and vitamin D are common in PD patients and can increase symptom severity. These vitamin deficiencies are related to the rise in homocysteine (a neurotoxic chemical).
Manganese Toxicity
Manganese (Mn) is an essential trace element necessary for physiological processes that support development, growth, and neuronal function. Overexposure or decreased ability to excrete manganese can cause an accumulation in the basal ganglia region of the brain and may cause a parkinsonian-like syndrome, referred to as manganism.
Functional Medicine Labs to Find the Root Causes of Parkinson's Disease
Your doctor is the best person to determine which of the root causes of Parkinson's could be playing a role in your symptoms. In pursuit of understanding your root cause(s) and developing a plan to help you optimize your health with PD, they may order some of the following tests.
Heavy Metals and Environmental Toxins
Screening for manganism is a high-yield way to rule out heavy metal contributors to Parkinson's disease. To detect heavy metal abnormalities, practitioners can check hair, blood, and urine to ensure none are above the reference range.
If findings are normal, but you still suspect you may have heavy metal toxicity, you can do a provocation challenge test, where you take a small dose of a heavy metal chelator and then check how much of that metal is excreted into the urine. To screen for exposures to chemicals like those found in pesticides, organic acids testing is a great option that avoids the blood draw and uses urine to screen for elevations.
Viral infections
Four common viral infections involved in neurodegenerative, inflammatory disorders such as Parkinson's are Epstein-Barr virus (EBV), Cytomegalovirus (CMV), Herpes Simplex Virus 1 (HSV-1), and Herpes Simplex Virus-2 (HSV-2).
Microbiome
Gut microbiome testing is made easy with collect-at-home kits that can be sent away and quickly analyzed in a lab.
Genetic Testing
Genetic testing can be a powerful tool to uncover biological pathways that cause Parkinson's disease (PD), and this understanding can lead to improved treatments and care for all people with Parkinson's
Mapping the Future of Parkinson's Disease is a national initiative that offers genetic testing for clinically relevant Parkinson's-related genes and genetic counseling at no cost for people with Parkinson's disease.
Hormones
A Complete Thyroid Panel should include at least TSH, Free T4, Free T3, and Reverse T3 to get a comprehensive overview of how well the thyroid is functioning. With The Dutch Plus Test, your practitioner can measure various sex hormones in the urine and saliva, including progesterone, testosterone, DHEA, cortisol, and estrogen. Your primary care practitioner can also run all of these tests at your annual physical.
Micronutrient Testing
If your doctor suspects you have a nutrient deficiency, they can run blood tests to determine which ones may be affecting you.
Specifically, markers like homocysteine and methylmalonic acid can be used to determine the functional status of vitamins like B12 and folate in the body.
A standard CBC and CMP that your doctor runs every year at your check-up can detect some B vitamin and iron deficiencies.
Additionally, a trained practitioner can help you evaluate your diet to see if your typical eating pattern has nutrient gaps that may impact the progression rate of your Parkinson's symptoms.
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Parkinsons Symptoms Management
The proper treatment protocol for any individual's Parkinson's disease will depend on their unique history, genetics, lifestyle, preferences, and symptoms. This is because functional medicine practitioners don't treat symptoms - they treat people! Standard functional medicine approaches to treating Parkinson's disease usually contain a combination of the following approaches.
Dopamine Replacement and Pharmaceuticals
L-dopa containing or modifying medications and herbs are the first step in PD treatment. This is because low dopamine levels in the brain can result in severe symptoms (like slow movements, trouble swallowing, impaired balance, etc.), making it challenging to implement the rest of the treatment approaches in this article. Replacing dopamine allows people with PD to improve their functioning to the point where they can adopt the lifestyle changes needed to keep them well.
L-dopa is available in pharmaceutical form as levodopa and herbal formulations of mucuna pruriens. There are issues using herbal preparations of L-dopa because manufacturing processes vary, which can make dosing tricky. For most people, using pharmaceutical forms of L-dopa is the best option.
In addition to dopamine replacement, there are other pharmaceutical options for improving symptoms in PD. These include dopamine agonists, MAO-B inhibitors, anticholinergics, and even some antiviral drugs. Choosing and dosing these pharmaceuticals usually requires specialist-level expertise, and it's recommended that everyone with Parkinson's disease see a neurologist as part of their care team to manage these medications regularly.
Diet and Supplements
Research suggests that diet, supplements, and lifestyle changes have a massive impact on Parkinson's symptoms. The Mediterranean diet effectively reduces many of the symptoms of Parkinson's disease. Also there is now mounting evidence that the beneficial effects of probiotics could suppress inflammation partially through the production of anti-inflammatory cytokines. The use of probiotics or synbiotics appears to be prophylactic agents against neurodegeneration, ultimately reestablishing a balanced gut-brain axis.
Additionally, several dietary supplements have been found to improve outcomes in PD.
- Glutathione
- DHEA
- Low dose lithium
- CoQ10
- Fish oil
- Quercetin
- Turmeric/curcumin
- Ginkgo biloba
- Resveratrol
- Vitamin D
- Alpha-lipoic acid
- 5-MTHF
- NADH
- Multivitamins
Supplements are not one-size-fits-all, and a trained functional medicine provider is the best person to help someone with Parkinson's determine which supplements may or may not benefit them as part of their treatment plan.
Exercise and Physical Therapy
Exercise and therapeutic exercise can improve motor symptoms, gait, balance, and strength in people with Parkinson's disease. It's recommended that people with Parkinson's work with a medical professional like a physical therapist to devise a safe and effective exercise program geared towards improving their mobility and strength. Additionally, because of the risk of falls and injuries in movement disorders like Parkinson's, it's important to exercise in an environment that is safe and staffed by trained professionals depending on the severity of motor impairment a person with Parkinson's experiences.
Hormones
If hormone disorders play a role in PD symptoms, a clinician can prescribe hormone replacement or work to eliminate the barriers to normal hormone production using a combination of lifestyle, nutrients, herbs, and pharmaceuticals.
Heavy Metals & Toxicity
If heavy metal toxicity is making PD symptoms worse, many chelation therapies are available that range from gentle and mild to more intensive supplemental or prescription chelation therapy.
If pesticide toxicity or exposure aggravates PD symptoms, a clinician may refer to a toxicologist or work to eliminate sources of exposure to naturally lower body levels of pesticides over time.
Multidisciplinary Approach
The best approaches to Parkinson's are multidisciplinary and involve a team. Usually, this team combines a primary care doctor, neurologist, physical therapist or exercise specialist, nutritionist, occupational therapist, functional medicine doctor, therapist, supportive friends and family, and more.
Caregivers for people with chronic and neurodegenerative disorders also need support. If you're a caregiver or close family member of someone with Parkinson's, make sure you're caring for yourself, as well!
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Summary
It's possible to thrive with Parkinson's disease, and it is your absolute right to use every tool available to get there. A skilled practitioner who knows your history can help you develop a multidisciplinary, multifaceted plan to get back to feeling happy, healthy, and in love with your life. Work with a provider who can help you build your multidisciplinary team to get the best care and the best outcomes possible.
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Lab Tests in This Article
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