What are the benefits of adding milk to coffee?

New research has found adding a little milk to your morning coffee may enhance the drink’s anti-inflammatory properties. Across several studies food scientists have demonstrated how milk proteins can bind with antioxidants in coffee, amplifying any potential health benefits.

The research focused on a family of organic compounds known as polyphenols. Found in lots of foods, polyphenols have antioxidant effects, reducing oxidative stress in a human body. However, surprisingly little is known about how polyphenols interact with other molecules found in food.

In two new studies, researchers from the University of Copenhagen zoomed in on one specific polyphenol interaction – caffeic acid and chlorogenic acid (the two main polyphenols found in coffee) and cysteine (a key protein in milk).

The first new study looked at the effects of these polyphenol-protein combinations on immune cells in lab conditions. The researchers then artificially inflamed those immune cells to see how effectively the polyphenol-protein combo prevented inflammation.

The results were impressive, with the protein-spiked polyphenols turning out to be twice as effective at preventing inflammation in the immune cells, compared to polyphenols alone.

“In the study, we show that as a polyphenol reacts with an amino acid, its inhibitory effect on inflammation in immune cells is enhanced,” said Marianne Nissen Lund, lead researcher on the study. “As such, it is clearly imaginable that this cocktail could also have a beneficial effect on inflammation in humans.”

The next step in the research was to investigate whether this specific polyphenol-protein bond takes place in a coffee drink with milk. Here, Lund and colleagues effectively showed commercial coffee beverages do generate these novel bound molecules.