I was wondering: Are there any foods, such as those containing antioxidants or probiotics, that can boost the immune system enough to protect against H1N1 or other influenza strains? - A.Z., Rishon Lezion Olga Raz, chief clinical dietitian at Tel Aviv Sourasky Medical Center, replies: Food is not a drug, so we can't expect that one food or another will strengthen our immune system. However, there are things you can do to strengthen your immune system in general: Keep your weight normal, eat vegetables, use olive oil, eat small meals every three to four hours, eat complex carbohydrates as a basic food, drink enough liquids (especially black and green tea), eat cold-water fish, be physically active, try not to get stressed, and be basically in a good mood and like other people and yourself. If so, there is good reason to believe your immune system will withstand the winter. We should be sure that our blood tests for iron, ferritin, vitamin B12 and vitamin D3 are normal, and if they are not, take appropriate additives after consultation with a clinical dietitian. Dr. Itamar Grotto, head of the Health Ministry's public health division, comments: There is no proven (evidence-based) effect for any food additive that may be helpful to prevent or treat influenza. Prof. Yehuda Shoenfeld, chairman of the Internal Medicine B department and the Center for Autoimmune Diseases at Sheba Medical Center at Tel Hashomer, adds: Vitamin D, which is beneficial for reducing the risk of many conditions, might be of help. Vitamin D has been shown to protect against tuberculosis. It seems that vitamin D may help the innate immune system to be more reactive against different infections. Almost all of us have a vitamin D deficiency, and taking it has no side effects. Prof. Meir Shalit, director of the clinical immunology and allergy unit in the internal medicine department at Jerusalem's Hadassah-University Medical Center, Ein Kerem, comments: It is correct that vitamin D helps protect against tuberculosis bacilli infection. However, to the best of my knowledge, no one has tested the effect of vitamin D on viral infections. Judy Siegel-Itzkovich adds: Other experts in a variety of specialties whom I consulted agreed that just eating probiotic yogurt or eating fruits with antioxidants such as (very expensive) blueberries would not be enough to stave off the flu. They stressed that it's a lot more complicated than that, adding that there isn't a single food or food group that can prevent getting infected with the flu, as the immune system is very complicated. Little scientific research has been conducted that has found what foods can boost the immune system at a specific moment, they said. Instead, people should adopt a lifestyle, hygienic habits and a good diet that in general promote the health of their immune systems. Where can I donate old eyeglass frames and/or frames with prescription lenses in them? I don't want to just throw them out. - D.G.G., Tel Aviv Prof. Ya'acov Peer, head of ophthalmology at Jerusalem's Hadassah-University Medical Center, Ein Kerem, comments: We in Hadassah do not accept old eyeglasses, and I really don't know who does. There is an optics shop in Jerusalem's Rehov Hahavatzelet run by a French-born optometrist who gives free eyeglasses to those in need, but I have no more details. Judy Siegel-Itzkovich adds: Any reader who knows of some place or person who accepts old prescription-lens eyeglasses for distribution among the needy can contact this column at email@example.com, and we will inform the readers. Readers welcomes queries from readers about medical problems. Experts will answer those we find most interesting. Write Rx for Readers, The Jerusalem Post, POB 81, Jerusalem 91000; fax your question to Judy Siegel- Itzkovich at (02) 538-9527; or e-mail it to firstname.lastname@example.org, giving your initials, age and residence.