“By the time you’re eighty years old, you’ve learned everything. You only have to remember it.”
— George Burns
Over the course of human history, views on aging have changed. Given the deadly attrition that occurred in ancient times from childbirth, childhood diseases, war, famine, plagues, and infectious diseases, reaching one’s golden years was viewed as a golden achievement worthy of at least respect, if not a degree of awe. Such people were often viewed as a communal resource, particularly in societies without information repositories like the Internet or written material; they were fountainheads of knowledge who often accompanied it with the wisdom of a lived experience.
In our modern age of increased life expectancy and data overload, that view has shifted. Today, growing older has increasingly become a source of dread. There is a huge societal focus – and business – on preserving the appearance of youthful vigor and vitality. But all the King’s cosmetic surgery, creams, and potions cannot put back together a mind that has cracked like an eggshell. For far too many, aging raises not the prospect of insight from a life well lived but physical infirmity and the Specter of cognitive loss in the mists of neurodegenerative disease.
This week’s study is a meta-analysis that examined the relationship between ultra-processed food intake and neurodegenerative disorders, including multiple sclerosis (MS), Parkinson’s disease (PD), Alzheimer’s disease (AD), cognitive impairment, and dementia.
- The meta-analysis reviewed 28 studies available through June 2023.
- The results revealed that increased ultraprocessed food consumption was associated with a:
- 15% increased risk of developing multiple sclerosis
- 56% increased risk of developing Parkinson’s disease
- 17% increased risk of cognitive impairment (specifically not dementia, including Alzheimer’s -type dementia).
- The review suggested the possible etiologies included:
- increased oxidative stress
- increased inflammation
- accelerated cell apoptosis (programmed cell death)
- increased immune system dysfunction
- gut dysbiosis.
The Caveat:
The significant increase in the risk of developing Parkinson’s disease in this review (56%) associated with increased consumption of ultraprocessed foods is particularly interesting, given significant corroborative experimental evidence. A previous meta-analysis (Romano, 2021) specifically examined Parkinson’s disease. This study and others have noted that the gut microbiota is emerging as an important modulator linked to an increased risk of developing Parkinson’s disease symptomatology and pathophysiology.
Parkinson’s disease is often preceded by gastrointestinal symptoms, and alterations of the enteric nervous system accompany the disease. In fact, it is now well recognized that Parkinson’s disease is multi-systemic, affecting the central as well as the peripheral nervous system, resulting in several non-motor symptoms, often including gastroparesis and constipation. Changes to the gut neurons may precede those seen in the brain by several decades.
Research has suggested significant and specific alterations in the gut microbiome of patients suffering from Parkinson’s disease. Specifically, there seem to be changes involving the bacterial genera Lactobacillus, Akkermansia, Bifidobacterium, Lachnospiraceae, and Faecalibacterium. These bacteria are involved in the production of short-chain fatty acids, the alteration of which could precipitate a pro-inflammatory state. This correlates to the documented increased gut permeability and inflammation observed in patients with Parkinson’s disease.
Given that Parkinson’s disease is the second most common neurodegenerative disorder after Alzheimer ’s-type dementia, any potential lifestyle interventions that could reduce risk, particularly dietary ones, are welcome options. Such findings harken back to the wisdom of the ancient sage Hippocrates, who is believed to have lived for over 90 years and warned us, “All disease begins in the gut.”
The Study:
Additional resources: