Can Milk Absorb Tea? The Nutritional Science Behind Your Favorite Brew

October 10, 2025 •

4 min read

According to one recent review, tea is the second most consumed beverage globally after water, with black tea accounting for 76–78% of global consumption, much of which is served with milk. This widespread habit raises a key nutritional question: can milk absorb tea compounds in a way that alters its health benefits? The answer lies not in simple absorption but in complex chemical interactions.

Quick Summary

Milk interacts with tea's polyphenolic compounds, but calling it absorption is inaccurate. The milk protein casein binds with tea flavonoids, which can reduce their antioxidant activity and bioavailability, though research provides conflicting evidence and long brewing times may lessen the effect. This combination also adds calories and nutrients like calcium from the milk, altering the overall nutritional profile of the beverage.

Key Points

Protein-Polyphenol Interaction: Milk proteins, especially casein, can bind with tea's antioxidant polyphenols, potentially reducing their effectiveness, but they do not simply 'absorb' them.
Conflicting Research: Studies on milk's effect on tea antioxidants show conflicting results, with some finding a reduction in activity while others find no significant change, especially in human studies.
Brewing Time Matters: Some evidence suggests that longer brewing times might increase the bioavailability of tea's antioxidants, potentially offsetting any binding effects from milk.
Iron Absorption is Different: Tea contains tannins that can inhibit non-heme iron absorption, a separate issue from adding milk. For this, avoiding tea with iron-rich meals is key.
Combined Nutritional Benefits: Adding milk provides extra nutrients like protein, calcium, and vitamins, adding to the beverage's nutritional profile, especially when sugar intake is controlled.
Personal Preference over Maximization: Given the mixed evidence, for most people, the decision to add milk can be based on personal preference and taste, rather than a strong health concern about eliminating all benefits.
Consider the Whole Diet: The overall dietary pattern is more important for health than whether milk is added to a single cup of tea. Moderation and balance are key.

Unpacking the Question: Milk's Interaction with Tea

When we ask, "Can milk absorb tea?", we're really exploring the complex biochemical interplay that happens when these two liquids are combined. The term 'absorb' can be misleading here; it's less about one liquid soaking up another and more about how the components within milk, specifically proteins, interact with the beneficial compounds in tea, known as flavonoids or polyphenols.

Tea, especially black and green varieties, is rich in flavonoids like catechins and theaflavins, which act as powerful antioxidants. Milk, meanwhile, contains a significant amount of casein, a type of protein. The core scientific concern is that casein can bind to the tea's flavonoids, potentially masking their antioxidant effects in the body. This interaction has been the subject of several studies, yielding a complex and often conflicting body of evidence.

The Science of Protein and Polyphenol Binding

The binding process between milk proteins and tea polyphenols is a key focus for food scientists. Research has identified several mechanisms for this interaction, including hydrophobic interactions, hydrogen bonding, and even covalent bonds, especially when heat is involved. Casein micelles, the primary proteins in milk, show a high affinity for tea polyphenols. This binding can potentially make the polyphenols less available to act as antioxidants. The degree of this interaction depends on factors like the tea-to-milk ratio, the type of tea and milk, and the brewing method.

How Casein Affects Antioxidant Activity

Studies on the effect of milk on antioxidant absorption have yielded conflicting results. Some in-vitro studies indicate a reduction in antioxidant activity, while some human-based studies have found no significant change in plasma antioxidant levels. It's worth noting that a longer brewing time might enhance the release and absorption of antioxidants, irrespective of milk addition.

Milk's Impact on Iron and Other Nutrients

Tea also contains tannins and oxalates that can hinder the absorption of non-heme iron. While adding milk is a separate issue, it's relevant for those with low iron. Milk itself is a source of calcium, but studies haven't shown that adding it to tea significantly impacts the bioavailability of tea flavonoids. Milk also provides other nutrients like protein and various vitamins.

Balancing Benefits and Drawbacks

Adding milk to tea is a matter of taste and tradition for many. It can smooth out the astringent or bitter notes of certain teas and adds calories, protein, and calcium. However, those prioritizing maximum antioxidant intake might consider plain tea. Managing specific health concerns might also lead to adjusting tea-drinking habits.

Comparison: Tea with Milk vs. Plain Tea


Feature	Plain Tea	Tea with Milk
Antioxidant Potency	High, especially in green and black teas; readily available polyphenols.	Potentially lower, due to binding with casein, though human studies show mixed results.
Nutritional Profile	Low-calorie, with antioxidants and minimal nutrients; contains some caffeine.	Adds protein, calcium, potassium, and vitamins from milk; higher calorie count, especially with sugar.
Flavor Profile	Distinct, often bitter or astringent flavor from tannins.	Creamier, smoother, and less bitter, which is preferred by many.
Impact on Iron Absorption	Tannins can inhibit absorption of non-heme iron if consumed near iron-rich meals.	Same inhibition from tannins; milk doesn't significantly alter this but adds calcium.
Gastrointestinal Effects	High consumption can cause dehydration due to diuretic properties.	Can cause bloating or indigestion in lactose-intolerant individuals.

Making a Mindful Choice for Your Diet

Given the conflicting evidence, the best approach depends on individual health goals and preferences. If maximizing antioxidant intake is the priority, plain tea might be slightly advantageous. However, for most people, the overall benefits of including tea in a balanced diet are significant, regardless of milk.

Consider lower-fat milk or plant-based options if watching calorie intake. Be mindful of added sugars, which can negate the health benefits of both tea and milk. For traditional milk teas like masala chai, spices like ginger and cardamom add their own health properties.

An occasional milky tea is unlikely to remove all health benefits. The overall diet has the biggest impact on health. Enjoy your tea how you like it, while keeping these nutritional points in mind.

Conclusion

Milk doesn't simply "absorb" tea's benefits. Instead, milk proteins, particularly casein, interact with tea's polyphenols, potentially reducing their antioxidant activity and bioavailability. The extent of this interaction varies in studies and depends on factors like brewing time and tea type. While some lab studies show a decrease, human studies have been mixed, with some indicating no significant effect on plasma antioxidant levels. The addition of milk adds nutrients but also calories and can be an issue for those who are lactose intolerant. For most people, moderate consumption of milky tea is a pleasant and potentially healthful habit. Those prioritizing maximum antioxidant potency might choose plain tea, but the broader dietary context is more impactful than the milk in a single cup of tea.

Frequently Asked Questions

Adding milk doesn't destroy antioxidants but can bind with them, potentially reducing their activity and absorption. However, human studies on the effect are conflicting, with some showing no significant impact on plasma antioxidant levels.

Milk tea can be a healthy beverage, combining the antioxidants of tea with the nutrients (protein, calcium) of milk. Its healthiness largely depends on sugar content and portion size; excessive sugar is a greater health concern than the milk itself.

Tea contains tannins that inhibit non-heme iron absorption. The addition of milk does not alter this specific interaction, though the combined effect of tea and milk is debated. For better iron absorption, it is best to avoid drinking tea with iron-rich meals.

It depends on your goal. Drinking plain tea may maximize antioxidant intake, but drinking tea with milk provides extra protein, calcium, and a smoother taste. Both are perfectly fine in moderation.

Brewing tea in milk, as done with traditional masala chai, is possible because milk is mostly water. However, the fat content of milk changes the extraction process, often requiring a stronger tea to maintain flavor. Brewing in water first and then adding milk is the most common method.

Yes, many people use plant-based milk alternatives like soy, oat, or almond milk in their tea. While plant-based milks have different protein compositions than dairy milk, they can also interact with tea compounds.

Adding milk can improve flavor by reducing astringency and contribute nutrients like calcium and protein.