How Coffee and Tea May Help Prevent Dementia and Offer Health Benefits

Numerous studies have linked coffee and tea to significant health benefits. Notably, they are associated with a lower risk of cardiometabolic diseases, which include type 2 diabetes, coronary heart disease, and stroke. A comprehensive study involving over 188,000 individuals found that moderate coffee and tea consumption correlates with the least likelihood of developing such conditions.

Further evidence highlights the heart-health benefits of coffee. According to the Framingham Heart Study, increasing coffee intake per week is linked to a diminished risk of heart failure and stroke. Individuals drinking 3–5 cups of coffee daily can lower their risk of cardiovascular issues by as much as 15 percent compared to non-consumers.

Tea consumption is also beneficial for bone health. A decade-long study following nearly 10,000 women over 65 revealed that those who frequently drank tea exhibited higher hip bone density. Even minimal improvements in bone density can significantly lower fracture risks.

Additionally, research has noted a correlation between coffee and reduced risks for specific diseases, such as colorectal cancer. A Dutch study involving colorectal cancer patients indicated that those consuming over four cups of coffee daily had a 37 percent lower chance of recurrence, while the highest survival rates were observed in those drinking 3-5 cups daily.

New research involving over 130,000 health professionals spanning 43 years suggests that caffeine intake from coffee and tea is associated with a lower risk of dementia. This study documented more than 11,000 dementia cases, and findings showed that higher caffeinated coffee consumption directly correlates with a decreased likelihood of developing dementia, while decaffeinated coffee did not yield similar results.

Optimal benefits are typically seen with moderate intake—about 2-3 cups of coffee daily or 1-2 cups of tea. Within this range, there’s a significant reduction in dementia risk and cognitive decline. Remarkably, consuming up to five cups of coffee each day can still result in an 18 percent lower dementia risk relative to infrequent consumers.

This aligns with findings from another large-scale study conducted by the UK Biobank, which included 365,682 participants. This research also indicated that consuming 2-3 cups of coffee or 3-5 cups of tea per day is related to the lowest incidences of both stroke and dementia. Additionally, combining 2-3 cups of coffee with the same amount of tea yielded a 32 percent reduction in stroke risk and a 28 percent reduction in dementia risk.

Nonetheless, researchers caution that these results are mainly observational and do not establish a direct cause-and-effect relationship. However, the extensive sample size and the duration of these studies make the results significant. Caffeinated coffee and tea are acknowledged as contributors to cognitive health as we age.

Caffeine appears to play a pivotal role in the protective effects against dementia. A long-term study found that decaffeinated coffee did not provide the same cognitive advantages as its caffeinated counterpart, suggesting that the benefits are closely tied to caffeine’s effects rather than just coffee’s other components.

Coffee is also rich in bioactive compounds, including antioxidants and phenolic substances, which are believed to have roles in cancer prevention. Research has identified two specific antioxidants in coffee—cafestol and caffeic acid—that may enhance insulin secretion and improve glucose absorption in muscle cells.

Tea’s health benefits are often linked to its polyphenols and the amino acid L-theanine. Studies indicate that L-theanine can create a calming effect within 30-40 minutes after consumption, which is achieved by increasing alpha brain wave activity and influencing neurotransmitters such as GABA, dopamine, and serotonin.

Furthermore, a study from King’s College London emphasized the positive impact of a diet rich in polyphenols (including tea and coffee) on heart health. Polyphenols, encompassing flavonoids and phenolic acids, are associated with improved blood pressure, higher levels of high-density lipoprotein (HDL) cholesterol, and a slower rise in cardiovascular disease risk as individuals age. This reinforces the idea that it’s not a single compound that provides benefits, but rather the synergy of multiple components.

Research consistently indicates that moderate consumption yields the best outcomes. The UK Biobank study revealed that drinking 2-3 cups of coffee or 3-5 cups of tea daily correlates with the lowest rates of stroke and dementia. Furthermore, a total daily intake of 4-6 cups combining both beverages also provides protective effects.

This reinforces the finding that moderate amounts of coffee are not only safe, but have the potential to provide wide-ranging benefits.

A comprehensive study of nearly three million individuals discovered that regular coffee consumption of about three cups per day is linked to a 17 percent decrease in the risk of all-cause mortality. Beyond merely prolonging lifespan, this consumption is also linked to an increase in healthy life expectancy by approximately 1.8 years, highlighting the extensive benefits of moderate coffee intake.

In terms of cardiometabolic health, moderate coffee consumption of around three cups daily, or an intake of 200-300 milligrams of caffeine, correlates with the lowest risk of developing new cardiometabolic conditions. This evidences that protection extends beyond just cognitive benefits to metabolism and cardiovascular health.

However, it’s crucial to monitor for excessive intake. Research involving older women found that consuming more than five cups of coffee daily can lead to decreased bone density. The FDA recommends a caffeine consumption limit of approximately 400 milligrams per day for adults, while pregnant women should aim for less than 200 milligrams.

Optimal benefits from coffee and tea hinge on the way they are consumed. For instance, the health advantages are greatly diminished when these beverages contain added sugars, creamers, or sweeteners. Excessive sugar can elevate the risk of obesity and diabetes. Ideally, the healthiest option is black coffee, devoid of high-calorie sweetened additions.

Timing also plays a significant role; for instance, drinking coffee in the morning may lead to an overload of cortisol, particularly between 7:00 and 8:00 a.m., causing increased anxiety or irritability in some individuals. Experts often recommend postponing coffee intake until after lunch.

A person’s sensitivity to caffeine can differ, influenced by genetic factors. The CYP1A2 gene allows some individuals to process caffeine more efficiently, thereby preventing sleep disturbances even if coffee is consumed later in the day. However, those who metabolize caffeine slowly are more likely to experience side effects such as heart palpitations and insomnia.

Specific groups must exercise caution. It is typically advised that children stay away from caffeinated drinks, while those with high blood pressure should limit their coffee intake. In older women, excessive consumption of coffee is linked to bone density decline. Thus, coffee and tea should be part of a comprehensive approach to a healthy lifestyle rather than a means to prevent diseases.