You make a great point about how important it is to question single results, especially when big claims are being made. I would also say that it is very important to find out if the Institute of Psychology in London is connected to or receives funding from any groups that could affect the results of their study. Results can sometimes be skewed by funding from businesses. Also, it might sound interesting to say that ice cream can make you happy and improve brain function, but did the piece or study take into account other factors, such as the placebo effect or the participants' normal eating habits? These could have a big effect on the results, and talking about them would make your case stronger.