What Benefits Does the Body Get from Drinking Tea and Water?

1. Drinking Tea

A study conducted by Huashan Hospital, affiliated with Fudan University in China, and published in the international journal Nature, has highlighted the real benefits of the habit of drinking tea.

According to the study, researchers tracked more than 370,000 people over nine years and found that those who regularly drink tea may reduce their risk of developing dementia by 16% compared to non-tea drinkers. The study also suggested that the optimal daily intake is three cups of tea (approximately 250 ml per cup).

Another study by experts from the University of Milan (Italy), published in the British Journal of Cancer, also pointed out the positive effects of tea consumption. By analyzing and comparing data between frequent tea drinkers and those who rarely drink tea, researchers found that regular tea drinkers have a lower risk of stomach cancer.

In addition, a 2020 study published in Advances in Nutrition showed that tea may help protect against various cancers, including stomach, colorectal, bile duct, liver, and especially oral cancer.

Meanwhile, the American Journal of Clinical Nutrition analyzed data from over 500,000 adults and found that people who drink tea daily may reduce their risk of diabetes by 8%. For those already diagnosed with diabetes, drinking green tea may also lower the risk of death from all causes.

2. Drinking Water

A study by the U.S. National Institutes of Health, published in the medical journal eBioMedicine, found that people who drink enough water tend to show fewer signs of aging and have a lower risk of chronic diseases, thereby potentially extending their lifespan.

Researchers used health data from 11,255 individuals aged 40–50 at the beginning of the study and followed them for 30 years. By the time the results were evaluated, the participants had reached an average age of 76.

The study specifically examined participants’ hydration habits through their blood sodium levels. Generally, the more water a person drinks, the lower their sodium levels.

The results showed that individuals with blood sodium levels higher than 142 mmol/L (a sign of inadequate hydration) were biologically up to 50% older than their actual age. At the same time, they had a 64% higher risk of chronic diseases such as heart failure, stroke, atrial fibrillation, peripheral artery disease, chronic lung disease, diabetes, and dementia compared to those with sodium levels between 137–142 mmol/L.

A large-scale study lasting 25 years, involving nearly 16,000 participants and recently published by the U.S. National Heart, Lung, and Blood Institute (NHLBI), reported similar findings. Specifically, adults who consistently drink enough water tend to be healthier, have fewer chronic illnesses, and live longer than those who do not drink enough water.

Which Is Better for Health and Longevity: Tea or Water?

Based on these studies, both drinking tea and maintaining adequate water intake provide significant health benefits. However, many health experts believe that water is better than tea, mainly because it does not contain caffeine, sugar, or other additives.

Drinking plenty of water not only helps maintain proper hydration but also allows minerals such as calcium and magnesium to be absorbed into the bloodstream and distributed throughout the body. This supports nutrient absorption, strengthens the heart and bones, and accelerates cellular metabolism, helping all organs function properly.

If you are a regular tea drinker, you can still increase your water intake. However, tea should not completely replace water, as many types of tea may contain added flavors or sugar. Excessive consumption can lead to unwanted health effects.

In addition, the caffeine in tea has a diuretic effect, which may lead to dehydration. Polyphenols in tea can also interfere with iron absorption, so it is not advisable to rely solely on tea without drinking water in your daily life.