The COVID-19 pandemic may be over, but our immune systems are still feeling the impact. After years of battling constant viral threats, from COVID-19 to seasonal flu and other infections, our body’s defense system is exhausted. Many people continue to experience lingering inflammation, frequent illnesses, and slower recovery times. This extended state of immune stress has compromised us further to chronic illness, including autoimmune diseases and even neurodegenerative diseases such as Parkinson's. So why is our immune system still in trouble? And how do we give it its power back? Understanding immune exhaustion is the beginning of rebuilding our body's natural immunity.

A weakened immune system makes people more susceptible to disease, mental illnesses, and even sleep disorders. Now, new research indicates that immune system depletion may play an important role in the onset of Parkinson's disease, a degenerative neurologic disorder that compromises movement and cognition.

Role of Inflammation in Parkinson's Disease

Dysfunctional immune response is a leading cause of long-standing inflammation within the body, that has been found to contribute towards a multitude of conditions, including cardiovascular conditions, diabetes, depression, and neurodegenerative diseases such as Alzheimer's.

As people age, their immune system naturally becomes less effective. This deterioration, referred to as immune exhaustion, may be a key contributor to the onset and progression of Parkinson’s disease. Rebecca Wallings, a Parkinson’s Foundation Launch Award grant recipient and senior postdoctoral fellow at the University of Florida, believes that an accumulation of exhausted immune cells could be driving neurodegeneration in Parkinson’s patients.

How a Tired Immune System Might Affect Parkinson's?

Parkinson's disease is most commonly linked with the degeneration and loss of dopaminergic neurons—motor nerve cells that produce dopamine, an essential neurotransmitter for movement. While researchers have long suspected inflammation is involved in this neurodegeneration, the mechanisms are not yet well understood.

Wallings' study is on immune cell exhaustion, a process by which aging immune cells fail to control immune responses effectively. Her research indicates that instead of dampening inflammation in Parkinson's patients, attempts should be made to rejuvenate the immune system to regain its functionality.

Energy Deficiency in Immune Cells

One of the major findings of Wallings' work is the function of mitochondrial impairment in immune cell exhaustion. Mitochondria are commonly called the powerhouses of cells, as they are vital for generating energy. As mitochondria age and become inefficient, immune cells fail to function well, potentially accelerating neurodegeneration in Parkinson's disease.

Wallings has found that mutations in the LRRK2 gene, a recognized genetic risk factor for Parkinson's disease, are linked with defective mitochondrial function and immune cell exhaustion. Her current work includes testing various therapeutic approaches to restore mitochondrial function in immune cells with the potential to enhance the immune system and potentially prevent or treat Parkinson's disease.

Will Rejuvenating the Immune System Help in Treatment?

For decades, the standard practice in treating Parkinson's has been to suppress brain inflammation. Yet Wallings' work indicates that instead of slowing down immune responses, restoring the immune system could be a more successful strategy. By addressing mitochondrial impairment and immune resilience, researchers can potentially reverse or slow down Parkinson's disease.

Wallings is now looking into how to rejuvenate immune cells by fixing mitochondria. She studies immune cells from patients with Parkinson's as well as from healthy subjects and performs experiments on animal models to determine if rejuvenation of the immune system could result in improved disease outcomes.

Lifestyle Factors That May Affect Parkinson's Risk

While there is no cure for Parkinson's disease, some lifestyle adjustments may decrease the chances of developing the illness. Since neurodegenerative diseases are associated with chronic inflammation and immune dysfunction, developing habits that enhance immune function might prove helpful.

Diet: There is evidence to suggest that eating in accordance with the Mediterranean or MIND diets, both high in antioxidants, healthy fats, and anti-inflammatory foods, can encourage brain wellness and reduce Parkinson's risk.

Avoiding Dangerous Substances: Restricting alcohol and nicotine use can maintain a robust immune system and suppress inflammation.

Reducing Stress: Chronic stress weakens immune function, so methods such as meditation, exercise, and sufficient sleep can lead to improved overall well-being.

Metabolism-Associated Fatty Liver Disease (MAFLD) — also termed Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) — is defined by excess hepatic fat accumulation (>5 per cent of liver weight) in the presence of metabolic dysfunction, independent of alcohol intake. It encompasses a spectrum from simple steatosis to steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma.

MAFLD: Epidemiology In India

A Lancet Regional Health study found that approximately 39 per cent of Indian adults screened had fatty liver disease, making it one of the most prevalent chronic liver conditions in the country. Within India, prevalence shows regional variation driven by genetic, dietary, and socioeconomic factors.

A particularly important feature is the “lean MAFLD” phenotype — South Asians often develop fatty liver at a lower BMI due to disproportionately high visceral fat, which complicates detection based on conventional BMI screening. Currently, MASLD is the commonest cause of liver cirrhosis and hepatocellular carcinoma (HCC).

MAFLD: Causes And Risk Factors

The core drivers are components of metabolic syndrome: type 2 diabetes mellitus, obesity (particularly central adiposity), dyslipidemia, hypertension, and insulin resistance. MASLD is strongly linked to obesity, sedentary lifestyles, and metabolic syndrome.

Genetic susceptibility also plays a role — variants in genes such as PNPLA3 are associated with increased liver fat accumulation, particularly in certain Indian populations. Rapid dietary transition towards ultra-processed, high-calorie foods compounds the risk.

MAFLD: Investigations

Routine liver function tests may appear normal in early stages, and an ultrasound detects only moderate-to-severe fat accumulation. A structured approach includes:

• Blood tests: LFTs, fasting glucose, HbA1c, lipid profile, insulin resistance indices
• Ultrasound abdomen: First-line imaging for steatosis
• FibroScan (Transient Elastography): Liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) are standardized non-invasive tools for assessing fibrosis and steatosis.
• Liver biopsy: Gold standard for staging steatohepatitis and fibrosis when non-invasive tests are inconclusive.

MAFLD: Treatment

No approved pharmacotherapy exists exclusively for MAFLD; management is lifestyle-centred:

• Weight loss: 7–10 per cent body weight reduction significantly reduces hepatic steatosis and inflammation
• Diet: Mediterranean-style diet; restrict refined carbohydrates and saturated fats
• Exercise: Both aerobic and resistance training improve insulin sensitivity and liver fat
• Metabolic comorbidity control: Optimise glycaemia (GLP-1 agonists show hepatic benefit), manage dyslipidaemia and hypertension
• Emerging therapies: Resmetirom (thyroid hormone receptor-β agonist) has shown promise in MASH with fibrosis.

Once known to affect only people over 60, Parkinson’s Disease is now increasingly being seen in young adults, especially at the age of 40, said health experts on World Parkinson’s Day today.

World Parkinson’s Day is observed every year on April 11 to raise awareness about the brain condition that causes tremors, slowness of movement, and trouble walking.

Parkinson’s is a progressive and neurodegenerative movement disorder caused by the loss of dopamine-producing brain cells.

Progressive decline in mobility is a key issue among Parkinson's patients, impacting their independence and quality of life. Other problems include slow movement, tremor, imbalance, cognitive impairment, mental health disorders, sleep disorders, and pain.

Also read: World Parkinson's Day 2026: Origin, Theme And Global Burden

Young-onset Parkinson’s Disease

According to the American Parkinson's Disease Association, a diagnosis of Parkinson’s between the ages of 21 and 50 is referred to as early-onset Parkinson’s disease, or young-onset Parkinson’s disease (YOPD).

Exposure to environmental toxins and lifestyle changes are major reasons for the rise in Parkinson's in this group.

While the symptoms of the disease are mostly the same at whatever age it develops, younger people will experience the disease differently due to their unique life circumstances. Managing the disease can be particularly challenging for a younger person and their family from a medical, psychological, and social standpoint.

"There is a perceived increase in younger-onset Parkinson’s in India. Possible reasons include better awareness and diagnosis (more neurologists, improved access to care), environmental exposures (pesticides, heavy metals), and air/water pollution. Lifestyle (sedentary habits) and urbanization-related factors may also contribute," Dr Sudhir Kumar, Neurologist at Apollo Hospitals Hyderabad, told HealthandMe.

A 2022 study, published in NPJ Parkinson's Disease, showed that the incidence of Parkinson’s disease, or the number of new cases diagnosed per year, is 50 per cent higher than previously estimated.

Instead of past estimates of 60,000 new cases of Parkinson’s disease diagnosed per year, the study determined that there are approximately 90,000 new cases of Parkinson's disease diagnosed in the US per year.

"Young-onset Parkinson’s disease (YOPD) is on the rise, mainly in the middle socio-demographic index. These countries include India, China, and some Southeast Asian countries," Dr Paresh Doshi, Director of Neurosurgery and Stereotactic & Functional Neurosurgery at Jaslok Hospital and Research Centre.

"According to one research paper, the age-standardized incidence rate has been rising at an alarming rate of 1.4 per cent per annum. To put it in perspective, if the incidence was 100/10,00,000 in 1995, it would be 153/10,00,000 in 2026," he added.

The experts noted that, along with the rising disability burden, mortality is reducing. The compound effect of all these is a larger number of YOPD patients suffering longer. Surgeries like deep-brain stimulation can help reduce these disabilities significantly.

Checklist for Parkinson’s: Signs You Should Not Ignore

Early recognition is critical, as many symptoms precede motor features by years.

Common early signs include:

• Reduced sense of smell (anosmia)
• Slowness of movement (bradykinesia)
• Reduced arm swing while walking
• Resting tremor
• Masked facies (reduced facial expression)
• Change in handwriting (micrographia)

Other important symptoms, which are often overlooked:

• Constipation
• Sleep disturbances (especially REM sleep Behavior disorder)
• Depression or anxiety.

Parkinson’s Disease is traditionally characterized by motor symptoms such as tremor and dyskinesia, although non-motor symptoms, in particular gastrointestinal (GI) symptoms such as constipation and incomplete emptying, are often the first markers of the disease and may precede the motor symptoms by years.

GI dysfunction is reported in approximately 70-80 per cent of Parkinson’s patients, mediated in large part through the gut-brain axis (GBA).

Speaking to HealthandMe, Dr Paresh Doshi, Director of Neurosurgery and Stereotactic and Functional Neurosurgery at Jaslok Hospital and Research Center, GBA, is an established two-way network that links the GI tract and the central nervous system (CNS). The connection is multifaceted, involving the vagus nerve, the enteric nervous system (ENS), the immune system, and a vast number of microbial metabolites and neuroendocrine signals.

“Constipation is seen in 66 per cent of Parkinson’s patients, attributed to disordered central and peripheral parasympathetic disruption, and can lead to alteration of the gut microbiome, which in turn worsens constipation, starting a feedback loop,” the doctor explained.

What Parkinson’s Patients Must Eat

Dr Sudhir Kumar, Neurologist at Apollo Hospitals Hyderabad, told HealthandMe that changes in the gut microbiome may influence inflammation, α-synuclein aggregation, and symptom progression.

Practical dietary principles for Parkinson’s patients include:

• Prefer fiber-rich, plant-based foods (vegetables, fruits, whole grains), which support gut microbiota
• Include fermented foods (curd, buttermilk), which may improve microbial diversity
• Reduce ultra-processed and pro-inflammatory foods
• Ensure adequate hydration (helps reduce the risk of constipation, a common non-motor symptom)
• Protein timing matters: Levodopa competes with amino acids for absorption.

These gut-targeted interventions are promising adjuncts to conventional Parkinson's therapy, and improving patient quality of life.

Parkinson’s Treatment With Dance, Art

Beyond gut-brain axis, research has proven that unconventional therapy, like dance and art, can improve Parkinson’s treatment.

A 2024 study published in the Scientific Reports found that tango, particularly Argentine tango, improved Parkinson's symptoms like thinking problems or balance issues. It also led to a significant improvement in recognizing emotions on people's faces.

Dr Kumar said dance therapy improves balance, gait, and coordination; provides rhythmic cueing, which enhances motor performance, and improves mood and motivation (dopamine-related pathways).

Similarly, art therapy has been shown to improve overall visual-cognitive skills and visual exploration strategies as well as general motor function in patients with Parkinson’s. The changes in brain connectivity highlight a functional reorganization of visual networks, as revealed by a study published in Parkinsonism & Related Disorders.

Dr Kumar said art and creative therapies are also helpful in enhancing cognitive engagement. It may help with executive function and emotional well-being and provide a non-verbal outlet for expression. However, these therapies work best as adjuncts, not replacements, to standard treatment, the expert noted.

World Parkinson’s Day 2026

World Parkinson's Day is observed annually on April 11 to raise global awareness of Parkinson’s disease, the world's fastest-growing neurodegenerative disorder.

It highlights the need for early diagnosis, research, and support for the nearly 10 million people living with the condition. The day marks the birthday of Dr. James Parkinson, who first described the disease in 1817.

The theme of World Parkinson's Day 2026 is "Bridge the Care Gap." It reflects a critical challenge that persists despite advances in medical research: many people living with Parkinson's still lack consistent access to specialist care, affordable treatment, and integrated support systems.

Parkinson's disease affected 11.9 million people in 2021 and will affect 25.2 million people globally by 2050, representing an alarming 112 per cent rise.