Drinking milk will make your runny nose worse.”I have patients who swear that milk makes them produce more mucous,” says Jennifer Collins, MD, an assistant professor and a physician specializing in allergy, asthma and immunology at the New York Eye and Ear Infirmary. However, she hasn’t been able to find any good research to support that—and neither have other doctors. In fact, when Australian researchers went so far as to collect and weigh the nasal secretions of 60 volunteers inoculated with the common-cold virus, they found no association between milk intake and mucous production. Scientists think that drinking milk may remind some people of the consistency of mucous or may coat their throat in a way that makes them think they’re feeling more phlegm. Collins notes that drinking milk fortified with vitamin D can help boost your energy, spur cell growth and help keep your immune system working optimally. Those who are firmly anti-milk (for whatever reason) can get their vitamin D from fish like swordfish, salmon and tuna, or from fortified orange juice or cereal.