The American Journal of Medicine published a study finding that 72 percent of asthma patients had adverse reactions to perfume. Few fragrances currently on the market today are actually deriving their scent from natural sources (most are synthetic). To figure out if a product is naturally scented, simply look at the ingredients list. If the word fragrance is listed then it usually means the scent was created in a laboratory. If essential oils are listed then the fragrance should be natural. Don’t have time to read labels or want to avoid possible irritation all together? Then go fragrance-free!