Doctors said adults can develop allergies to foods and other substances that they have tolerated for years. In February this year, a typical day for Ms Teo Ying Ying turned into a distressing hospital visit and a confronting new chapter of her life. The 27 - year-old music teacher had enjoyed her favourite Indian rojak for both lunch and dinner, ending the day with a bowl of her mother's herbal soup. It wasn't long before her eyes started to itch and water uncomfortably. Then, she began