What research says on drinking black coffee before a workout and other health effects of coffee

Health effects of coffee: Caffeine is a known ergogenic aid; it helps improve athletic performance and physical activity levels. (Photo by Miriam Alonso via Pexels)

If your day begins with coffee, you're hardly alone. A lot of research has been done lately on the impact coffee has on our health, mood, longevity, fitness and athletic performance. New scientific research has given us reason to believe that coffee is a good thing to include in your daily life as it improves your quality of life, health, longevity and even strength.

“Coffee is a rich source of caffeine, which is a stimulant. It increases alertness and focus along with concentration and mood by altering the levels of various neurotransmitters like dopamine and adenosine. The presence of antioxidants like chlorogenic, ferulic, caffeic, and n-coumaric acids help fight inflammation and neutralise the harmful free radicals in our body. Moderate consumption of coffee can also help reduce the risk of diseases like type 2 diabetes, Parkinson’s disease, Alzheimer's disease and certain types of cancers due to its antioxidant properties,” explains Fiona Sampat, clinical dietitian at the Kokilaben Dhirubhai Ambani Hospital in Mumbai.

Consumption of black coffee, a low-calorie beverage, could aid in weight loss as it helps control levels of ghrelin, the hunger hormone, in our body. (Photo by Lisa Fotios via Pexels)

Coffee consumption is also linked to improved liver health and lower all-cause mortality. “Coffee has a great impact, specifically on the liver. There is a potential beneficial effect of coffee on the severity of liver fibrosis in fatty liver. The optimum quantity and form or preparation method of coffee required to exert this hepatoprotective role remains unclear. Coffee is a complex beverage containing more than 100 compounds. Its protective effects could be due to compounds other than caffeine,” says Dr Pankaj Puri, director of gastroenterology and hepatobiliary sciences, Fortis Escorts Hospital, Okhla, New Delhi.

The American Heart Association recommends that adults consume 300–350 milligrams of caffeine per day, which you can find in about three cups of coffee, says Vaishali Verma from HCMCT Manipal Hospital’s department of dietetics at Dwarka in New Delhi. “Coffee improves your mental health and awareness. It also improves exercise performance, concentration level and helps detoxify the liver. It creates a healthy liver enzyme too,” added Verma.

Scientific evidence backs what these health professionals say. A large cohort study published in the journal Annals of Internal Medicine in May 2022 found that moderate consumption of coffee—with or without sugar—was associated with lower risk for death and all-cause mortality. The study conducted in the United Kingdom from 2009 to 2018 tracked 171,616 people and took into account factors like their age, sex, ethnicity, educational level, smoking status, physical activity, body mass index, diet and coffee drinking habits. The average age of participants was 55.6 years. The study concluded that people who drank unsweetened coffee—irrespective of whether the coffee was instant, ground or decaf—had the lowest risk of death compared to those who did not drink any coffee at all. Those who drank 2.5-4.5 cups of coffee per day had 29 percent lower risk of death. For those who drink their coffee with sugar, the risk of death was lower especially for those who drank 1.5-3.5 cups a day.

A separate study published in 2022 in the BMC Public Health journal showed that all kinds of coffee decrease the risk of adverse outcomes in chronic liver disease. The researchers included 494,585 participants with known coffee consumption, hospital, death and cancer records in the study. Compared to non-coffee drinkers, coffee drinkers had about 20 percent lower risk of liver disease. Coffee drinkers also had 49 percent lower risk of dying from chronic liver disease. While all kinds of coffee led to a reduction in risk, ground coffee was found to be the best at doing so.

The caffeine in coffee is a stimulant, which increases alertness, focus and concentration. It also improves mood by altering the levels of neurotransmitters like dopamine and adenosine. (Photo by Arina Krasnikova via Pexels)

Another study published in 2020 established a relationship between coffee and better athletic performance. The study, published in the International Journal of Sport Nutrition and Exercise Metabolism, found that coffee that delivered 3 mg/kg of caffeine pre-workout improved 5-km cycling time-trial performance among amateur and recreational cyclists. The scientists explained this happens because caffeine attenuates pain sensation and perceived exertion, which tended to make people feel that they were putting in less effort and/or performing better. Another study demonstrated that the caffeine from coffee improved reaction times. The best bit of coffee news in recent times came from Finland—where researcher found that coffee consumption might decrease the risk of depression. Their findings were published in an article in Cambridge University’s Public Health Nutrition journal. The scientists further found there was no similar association between reduced risk of depression and caffeine or tea.

A two-decade-long study conducted by the National University of Singapore and sponsored by Starbucks found that regular consumption of coffee and tea—drinks containing caffeine—in your middle years leaves you stronger in your old age. The study was published in July 2023. “Compared with non-daily drinkers, those who drank four or more cups of coffee daily had reduced odds of physical frailty,” concluded the researchers.

The benefits are not restricted to coffee alone. Drinking tea, the world’s most consumed beverage, also has some health benefits. Moderate tea consumption is associated with lower risk of stroke and dementia. The National University of Singapore study found coffee-like benefits for those who consumed tea as well. “Higher consumption of caffeine at midlife, via coffee and tea, was associated with a reduced likelihood of physical frailty in late life,” they concluded.

Consumption of coffee in moderate amounts has been linked to reduced risks of liver conditions such as liver scarring, liver cancer and liver cirrhosis. (Photo by Karolina Grabowska via Pexels)

“Like coffee, tea is also an extremely rich source of antioxidants, especially green tea. It helps fight inflammation and reduces the risk of various types of cancers and heart disease,” says Sampat of Kokilaben Dhirubhai Ambani Hospital. Green tea’s antioxidants protect the skin from free radical damage, which results in wrinkles and ageing of the skin. The polyphenols and flavonoids in it strengthen our immune systems and increase our resistance to infection, she adds.

Shweta Gupta, head dietician at Fortis Hospital Shalimar Bagh in New Delhi, says tea is rich in antioxidants known as catechins, which are associated with various health benefits ranging from improved heart health and weight management. Tea also contains L-theanine, an amino acid that promotes relaxation and focus.

Side-effects of coffee

So, drinking coffee can have some positive effects for health, but can too much be bad for you? Yes, say experts. Over-consumption of coffee may cause insomnia, anxiety, increased heart rate, digestive issues, and even anaemia, says Gupta.

Coffee can act as diuretic if consumed in excess, leading to dehydration and loss of water-soluble vitamins and minerals. Excessive tea consumption, particularly strong black tea, may lead to excess caffeine intake and related side-effects like increased blood pressure.

“Both coffee and tea can stain teeth, and excessive consumption of very hot beverages may be linked to an increased risk of oesophageal cancer,” adds Gupta. Drinking too much tea or coffee alone can also cause gastric disturbances like nausea, heart burn and acid reflux.

Excessive coffee can worsen panic attacks and cause jitteriness, anxiety, and palpitations that ultimately increase blood pressure levels. Coffee’s effect on stomach acid production has sparked concerns about the possibility of a rise in dyspepsia, which is characterised by heartburn, eructation, nausea, poor digestion, and gas.

Other possible side effects include oesophageal burns, gastritis or ulcers, and gastrooesophageal reflux disease (GERD). The presence of caffeine and tannins in coffee and tea reduces the absorption of various minerals like manganese, zinc, copper and irons amongst others.

Consumption of both coffee and tea can be addictive. People develop a tolerance to caffeine when they ingest it routinely. It either ceases to function as before or requires a higher dosage to provide the same results. Caffeine withdrawal symptoms include headaches, tiredness, mental fog, and irritation when a person ceases to consume it.

Balance is key for enjoying the benefits of these beverages while minimizing risks.