Tea with milk is considered a traditional drink in many cultures
Millions of people start their morning with a cup of tea to which they add milk. In India, the United Kingdom, and CIS countries, this is such a familiar ritual that the idea of it being dangerous sounds absurd. But articles frequently surface online claiming that when tea flavonoids mix with milk casein, a “chemical compound” forms that poisons the body. They say that tea with milk destroys the liver and kidneys, acidifies the blood, and even causes impotence.
What Are Flavonoids in Tea and Casein in Milk
To evaluate the arguments from both sides, you need to understand what substances we’re talking about. Flavonoids are a group of natural compounds found in fruits, vegetables, chocolate, wine, and in especially high concentrations — in tea. Flavonoids have antioxidant and anti-inflammatory properties. Simply put, they help protect cells from damage and reduce the risk of cardiovascular diseases.
Casein is the main protein in milk, accounting for about 80% of all milk protein. It plays a role in muscle building and is well absorbed by the body. There is nothing dangerous about it on its own.
So, both components separately are not just safe — they are beneficial. But what happens when they end up in the same cup?
Why Tea with Milk Is Considered Harmful
To be fair, the alarming claims do have a real biochemical basis. Flavonoids do indeed bind with proteins, including casein. This is not a fabrication — it is a confirmed fact. A 2009 study showed that adding milk to black tea reduces its antioxidant capacity. Casein literally “intercepts” the flavonoids, and they are absorbed less effectively by the body.
Researchers also point out that milk can weaken the vascular effects of tea. In other words, if you drink tea for heart health benefits, milk partially neutralizes those benefits.
Additionally, tea itself has a slightly acidic reaction. And if you add sugar to tea with milk, as most people do, the acid load on the body increases. Sweetened tea with milk can indeed increase acidity and, with regular overconsumption, contribute to health problems.
Against this backdrop, the claims from the viral video start to sound not so crazy after all. Binding of beneficial substances, reduced antioxidant protection, increased acidity — isn’t that cause for concern?
What Science Says About the Harm of Tea with Milk
And this is where it gets really interesting. A reduction in antioxidant activity is not the same as poisoning. Flavonoids that have bound with casein are simply absorbed less efficiently. They do not turn into a toxic substance. No “poison” is formed when tea and milk are mixed.
Milk casein binds with tea antioxidants and reduces their absorption, but in exactly the same way, tea reduces the absorption of nutrients from any food it is consumed with. This is a normal food interaction, not a chemical catastrophe.
This will reduce the availability of antioxidants for the body, but it will not harm your health, — experts emphasize.
What else does science say about tea with milk:
- Liver. A 2010 study showed that liver damage in people was caused only by comfrey tea contaminated with pyrrolizidine alkaloids — toxic plant substances. Regular black or green tea with milk has nothing to do with this;
- Kidneys. A 2023 study showed the opposite: moderate consumption of tea with milk was associated with a significantly lower risk of acute kidney injury;
- Impotence. A 2016 study found that foods and beverages rich in flavonoids were, on the contrary, associated with a reduced risk of erectile dysfunction;
- Blood acidity. According to Healthline, adding milk to tea can actually reduce stomach acid production compared to plain tea. The problem arises more from sugar than from milk itself.
It turns out that most of the scary claims from the viral video are not only unconfirmed — they directly contradict the available scientific evidence.
Can You Drink Tea with Milk Every Day
If tea with milk isn’t poison — does that mean you can drink it in unlimited quantities? Not quite. Dietitians recommend limiting consumption to two cups a day. Tea with milk does not provide the body with essential nutrients, even if it contains antioxidants. Overconsuming any beverage, whether coffee, juice, or tea, is not beneficial.
Additives are a separate story. If you put three spoonfuls of sugar in your cup and drink five cups a day, you will have problems — but not because of the interaction between casein and flavonoids, rather because of excess sugar. That is an entirely different mechanism.
Where Do the Myths About Tea with Milk Come From
India is the second-largest tea producer in the world. According to the Tea Board of India, the country produced over 1,365 million kilograms of tea in 2022, and consumed more than 1,168 million kilograms domestically. Tea with milk is part of the national culture. That is precisely why a video claiming this drink is “poisonous” garnered millions of views: it strikes at a daily habit of a vast number of people.
Such claims are often based on real biochemical facts but taken to the point of absurdity. Yes, casein binds flavonoids — that is true. But “reduces benefits” and “poisons” are fundamentally different things. Trindade recommends always checking the author’s qualifications and the scientific data they reference before believing such claims.
The final verdict is simple. The claim that tea with milk is poison is false. Milk does reduce the antioxidant activity of tea, but it does not create any toxic substances. Two cups a day is a safe amount, and the main real danger lies not in the milk, but in the sugar we generously add to that tea. If you are concerned about getting maximum benefits from tea, drink it without milk. If you enjoy the taste, drink it with milk and don’t worry. Science is on your side.
