Mayo Clinic: "Mayo Clinic Q and A: Keeping hands consistently clean one of the best ways to avoid getting sick," "Supplements to Avoid when Dealing with High Blood Pressure," "Cold remedies: What works, what doesn't, what can't hurt," "Water: How much should you drink every day?"<br>PubMed Health: "Garlic for the common cold."<br>University of Maryland Medical Center: "Garlic."<br>CDC: "Water and Nutrition."