Unsweetened coffee may be associated with reduced risk of Alzheimer’s and Parkinson’s diseases, study finds

Recent research has shown that older adults who consume more caffeinated coffee, especially unsweetened coffee, are less likely to suffer from Alzheimer’s disease, related dementias, and Parkinson’s disease. This association was not observed for sweetened or artificially sweetened coffee. The research was published in the American Journal of Clinical Nutrition.

Alzheimer’s and Parkinson’s diseases are the most common neurodegenerative diseases and are among the leading causes of disability and dependency in aging populations worldwide. Estimates indicate that these conditions currently affect more than 63 million people worldwide.

Alzheimer’s disease is a progressive neurological disorder that affects memory, thinking and behavior, making it the most common cause of dementia. It usually begins with mild memory loss and gradually worsens, interfering with daily life and independence. The disease is characterized by the buildup of amyloid plaques and tau tangles in the brain, which leads to brain cell death. Although there is no cure, treatments focus on managing symptoms and improving quality of life.

Parkinson’s disease is a progressive neurological disorder that primarily affects movement due to the degeneration of dopamine-producing neurons in the brain. Common symptoms include tremor, stiffness, slow movements (bradykinesia), and difficulty with balance, which get worse over time. Non-motor symptoms, such as sleep disturbances, depression, and cognitive changes, may also occur.

Study author Tingjing Zhang sought to examine associations between coffee consumption and risk of neurodegenerative diseases. Unlike previous studies, this research also took into account the type of coffee consumed.

The researchers analyzed data from the UK Biobank, a large-scale biomedical database containing health, genetics and lifestyle information on around 500,000 people living in the UK. This resource is available for research analyzes to researchers worldwide.

Data for this analysis comes from 204,847 UK Biobank participants who completed dietary assessments between 2009 and 2012. Participants were aged 40 to 69 and 55% were women.

Coffee consumption data were collected using Oxford Web-Q, an online questionnaire that asked participants to recall the types and quantities of foods and drinks they had consumed during of the previous 24 hours. Participants completed this questionnaire five times over the course of a year, allowing researchers to examine variations in food and beverage consumption.

Participants reported the amount of coffee consumed in the previous 24 hours. Based on their responses, they were classified into four groups: non-coffee consumers, unsweetened coffee consumers, sweetened coffee consumers, and artificially sweetened coffee consumers. Participants who reported consuming coffee during at least one dietary recall were classified as coffee consumers, while those who did not were classified as non-coffee consumers. Those who consistently consumed the same type of coffee across different recalls were identified as single consumers, while others were classified as overlapping consumers and excluded from the analysis.

The results showed that around 54% of participants consumed unsweetened coffee, while 24% did not drink it at all. Sweetened coffee was consumed by 16% of participants, and the remaining 7% drank artificially sweetened coffee. Participants who didn’t drink coffee generally preferred tea.

Those who consumed more unsweetened coffee had a 29% to 30% lower risk of developing Alzheimer’s disease, related dementias, and Parkinson’s disease, as well as a 43% lower risk of dying from these diseases, compared to those who consumed more unsweetened coffee. non-coffee drinkers. In contrast, consumption of sweetened or artificially sweetened coffee was not associated with a reduced risk of these diseases or associated mortality.

Further analysis of caffeine content found that decaffeinated coffee consumption was associated with a 34-37% lower risk of Alzheimer’s and Parkinson’s diseases and a 47% lower risk of associated mortality, compared to non-caffeinated coffee. -coffee drinkers. These associations were absent among consumers of sweetened or artificially sweetened decaffeinated coffee.

“Our study reveals significant negative associations between unsweetened caffeinated coffee consumption and risk of Alzheimer’s disease and Parkinson’s disease (Alzheimer’s disease and related dementias and Parkinson’s disease), as well as associated mortality. This highlights an important public health message: adding sugar or artificial sweeteners to coffee can have harmful effects and should be approached with caution. Instead, the recommendation leans toward drinking unsweetened, caffeinated coffee,” the study authors concluded.

Although the study highlights links between coffee consumption and neurodegenerative diseases, its design does not allow causal conclusions to be drawn. It remains unclear whether coffee consumption reduces the risk of these diseases, whether these diseases (or their early symptoms) influence drinking habits, or whether a third factor affects both disease risk and consumption. of drinks.

The article entitled “Associations between different types of coffee, neurodegenerative diseases and associated mortality: results of a large prospective cohort study” was authored by Tingjing Zhang, Jiangen Song, Zhenfei Shen, Kewan Yin, Feifei Yang, Honghao Yang, Zheng Ma, Liangkai Chen, Yanhui Lu and Yang Xia.