Sufferers were given the probiotic, Bifidobacterium longum, over the 13 weeks that they were allergic to pollen, and a similar group was instead given a placebo. The probiotic group reported a dramatic improvement in their allergic reactions while they took the probiotic, and they reported an overall 40 per cent reduction of symptoms, such as itchy eye and throat, sneezing and nasal blockage, compared with the placebo group.

Although previous studies have shown that a probiotic can help ease allergic symptoms in children, this is one of the first to record successful treatment in adults.

(Source: Townsend Letter, 2008; 298: 52).