Two single vodka and orange drinks can slow reactions in seniors, researchers in the Netherlands and the United States suggest.

Judith Hegeman led a team of researchers at Saint Maartenskliniek in Nijmegen, Netherlands, who found just two drinks were enough to cause senior volunteers to struggle when walking through an obstacle avoidance test.

The study, published in BioMedCentral Research Notes, involved 13 healthy men and women with an average age of 61.5 years.

The researchers asked the volunteers to walk on a treadmill. Once they had attained a steady walking pace, a thin wooden block was placed at the far end of the belt and allowed to move toward the volunteer.

Ingesting alcohol had an effect on how capable the study subjects were of stepping over the wooden block.