Imperial College London’s research concluded that the speed at which caffeine is metabolised could have an impact on weight
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Combining milk protein with the antioxidants in coffee makes immune cells twice as effective at fighting inflammation

Whenever bacteria, viruses and other foreign substances enter the body, our immune systems react by deploying white blood cells and chemical substances to protect us.

This reaction is known as inflammation. It also occurs whenever we overload tendons and muscles and is a characteristic of diseases like rheumatoid arthritis. Coffee beans are filled with the antioxidant, polyphenols, naturally occurring antioxidants, important for humans.

They help reduce oxidative stress in the body that gives rise to inflammation. They are found in humans, plants, fruits and vegetables.

These antioxidants are also used by the food industry to slow the oxidation and deterioration of food quality.

To investigate the anti-inflammatory effect of combining polyphenols with proteins, the team from the University of Copenhagen applied artificial inflammation to immune cells.

Some of the cells received various doses of polyphenols that had reacted with an amino acid, the building block of proteins. Other cells only received polyphenols in the same doses and a control group received nothing.

The team found that the immune cells treated with the combination of polyphenols and amino acids were twice as effective at fighting inflammation.

Senior author Andrew Williams, an associate professor from the department of veterinary and animal sciences, said: “It is interesting to have now observed the anti-inflammatory effect in cell experiments. “And obviously, this has only made us more interested in understanding these health effects in greater detail.

The coffee to milk ratio – as well as foam to steamed milk – is highly specific for most drinks


“So, the next step will be to study the effects in animals.”

Professor Marianne Nissen Lund from the department of food science, who headed the study, said: “Our result demonstrates that the reaction between polyphenols and proteins also happens in some of the coffee drinks with milk that we studied. “In fact, the reaction happens so quickly that it has been difficult to avoid in any of the foods that we’ve studied so far.” These results suggest that this could be the case with other foods that contain this combination.

Professor Nissen Lund said: “I can imagine that something similar happens in, for example, a meat dish with vegetables or a smoothie, if you make sure to add some protein like milk or yoghurt.”

Industry and the research community are now working on how to add the right quantities of polyphenols in foods to achieve the best quality.

Dr Nissen Lund said: “Because humans do not absorb that much polyphenol, many researchers are studying how to encapsulate polyphenols in protein structures which improve their absorption in the body.

“This strategy has the added advantage of enhancing the anti-inflammatory effects of polyphenols.”

She added: “In the study, we show that as a polyphenol reacts with an amino acid, its inhibitory effect on inflammation in immune cells is enhanced.

“As such, it is clearly imaginable that this cocktail could also have a beneficial effect on inflammation in humans.

“We will now investigate further, initially in animals. After that, we hope to receive research funding which will allow us to study the effect in humans.”