Caffeine in Green Tea Vs. Black Tea

Nothing can beat a cup of coffee on those busy days when you're up from dusk 'til dawn. But, what about the content of caffeine in green tea versus black tea? Although both types of tea are lower in caffeine than a cup of java, they offer other nutrients with health-promoting properties.

About 90 percent of Americans start the day with caffeine-infused beverages. In fact, caffeine is the most popular psychoactive substance worldwide — and for good reason. It energizes your senses, increases alertness and lifts your mood, among other beneficial effects. On top of that, it may even help you get leaner and make it easier to maintain a healthy weight.

Most people consume caffeine in one form or another since childhood. Soda, energy drinks and chocolate all contain this stimulant. Caffeine is also added to certain medications, such as those used to counteract drowsiness, improve asthma symptoms or reduce blood pressure, reports a May 2017 review featured in ​Frontiers in Psychiatry​.

This review reports that caffeine is clinically proven to enhance cognition, increase wakefulness and reduce pain. Furthermore, it appears to have beneficial effects on the vascular system.

​Read more:​ 14 Legit Ways Coffee Can Boost Your Health

But, like most drugs, it's not entirely safe — especially when used in high doses. The ​Frontiers in Psychiatry​ review points out that caffeine may cause an irregular heartbeat and palpitations. These adverse effects are more likely to occur in people with heart disease.

Even healthy individuals may experience problems due to caffeine. According to the above review, caffeine consumption immediately before exercise reduces blood flow to the heart muscle. Certain populations, such as babies, are more sensitive to its side effects. For example, nursing infants whose mothers consume more than 200 milligrams of caffeine (about two cups of coffee) per day may have trouble sleeping and may exhibit behavioral issues.

As the Food and Drug Administration notes, caffeine is likely safe when consumed in small doses. Ideally, try not to exceed 400 milligrams per day — that's about four or five cups of coffee. If you're pregnant or sensitive to its side effects, aim for a lower dose or avoid stimulants altogether. One way to reduce your caffeine intake is to switch to green or black tea.

Green and black teas are loaded with antioxidants and phytonutrients that support overall health. Both varieties come from the ​Camellia Sinensis​ plant and possess anti-cancer, anti-diabetes and cardioprotective effects, according to a January 2013 research paper published in ​Current Pharmaceutical Design​. Due to their high antioxidant content, these healthful beverages may reduce oxidative stress, improve glucose metabolism and reduce blood lipids.

When it comes to the caffeine in green tea versus black tea, both beverages contain smaller doses of this stimulant than coffee. A cup of green tea provides 25 to 29 milligrams of caffeine, while the same amount of black tea contains 25 to 48 milligrams, a much larger range. However, decaf black tea has no more than 5 milligrams of this compound per cup, as reported by the Mayo Clinic.

Coffee, on the other hand, boasts 95 to 165 milligrams of caffeine per cup. Decaf versions contain the same amount of caffeine as decaf black tea. Instant coffee delivers about 63 milligrams per cup, which is still higher than the caffeine of tea.

If you are concerned about caffeine intake, should you stick to coffee or switch to tea? From a health perspective, the caffeine in green tea versus black tea is less important. What matters most is their nutritional value.

According to a review featured in ​Global Advances in Health and Medicine​ in March 2014, both types of tea may lower blood pressure and LDL (the "bad") cholesterol levels in just three to six months. Plus, they have little or no side effects. The polyphenols in black tea may also inhibit tumor growth, reduce blood sugar and improve insulin response.

​Read more:​ 10 Everyday Ailments Soothed by Tea

Green tea may be even more beneficial. As it turns out, this beverage is more effective at reducing blood pressure than black tea, reports an article published in ​Molecules​ in May 2019. Researchers attribute this beneficial effect to its high content of EGCG (​epigallocatechin 3-gallate​) and other catechins, a class of antioxidants. Furthermore, green tea consumption has been linked to a higher likelihood of healthy aging.

As mentioned earlier, caffeine may aid in weight loss. However, this doesn't mean you should stick to coffee.

Black and green tea polyphenols may help you slim down too, according to another review featured in ​Molecules​ in May 2018. These compounds may reduce sugar and fat absorption by inhibiting the digestive enzymes that break down glucose and lipids. They may also inhibit the formation of new fat cells and increase fat burning.

​Read more:​ The Effect of Black Tea on Weight Loss

At the end of the day, choosing between coffee and tea is a matter of personal preference. Green and black teas contain less caffeine and carry fewer side effects than a cup of joe. However, if you're highly sensitive to stimulants, you may need to give up caffeine altogether. Discuss your options with a medical professional, especially if you're pregnant, breastfeeding or suffering from cardiovascular problems.