Adding milk to tea can lower its antioxidant levels by between 11% and 75%, according to health publication Verywell Health.
Tea ranks as the most popular beverage in the world after water, and many drinkers routinely add a splash of milk to soften its flavor. However, health experts warned that combining dairy with tea can significantly weaken the protective health benefits of the brew.
All traditional tea comes from the leaves of the Camellia sinensis plant, an evergreen shrub renowned for its high concentration of antioxidants. Antioxidants are natural compounds that protect human cells against damage by binding to free radicals and preventing oxidation in the body.
When milk is poured into tea, casein, a principal protein found in dairy milk, binds directly to tea polyphenols, which act as antioxidants. Verywell Health reported that this binding process lowers the overall antioxidant activity of the tea and makes it more difficult for the human body to absorb the compounds. The outlet noted, however, that milk does not eliminate antioxidants entirely, leaving active beneficial compounds in the cup.
Impact of milk fat content
The extent to which milk reduces antioxidant levels depends heavily on its fat content. Drinkers select various dairy options, ranging from creamy whole milk to lighter skimmed milk, but each affects antioxidant preservation differently.
An older study cited by the publication evaluated antioxidant concentrations in five separate brands of black tea before and after adding whole, semi-skimmed, and skimmed cow milk. Adding milk reduced antioxidant levels across all five black tea brands tested.
Skimmed milk caused a significantly sharper reduction in antioxidant levels than whole milk or semi-skimmed milk. Researchers concluded that the higher fat content in whole milk helps shield tea antioxidants from binding with proteins.
Brewing time and tea varieties
Brewing time also influences the total antioxidant strength of a cup of tea. Research shows that longer steeping periods generate higher amounts of antioxidants than shorter brewing times, producing a stronger tea with richer antioxidant content.
The type of tea selected also plays a major role in antioxidant availability. Green tea naturally contains a higher level of antioxidants than black tea, although both varieties remain rich sources. A single cup of matcha, a finely ground powdered green tea, delivers 10 times the antioxidant content of standard green tea.
Furthermore, consumers add milk to green tea far less frequently than to black tea. This habit allows green tea to maintain a higher proportion of its natural antioxidant potential when consumed.
Related health guidance
In separate health advice, experts previously outlined daily consumption guidelines for nuts, confirming that the recommendations apply equally to tree nuts and peanuts. Nutritionists also highlighted fruit as a convenient pre-workout snack that provides essential carbohydrates to fuel athletic performance.
