A study by Yale University has found that health and government groups regularly spend millions advertising on websites that promote health misinformation, sometimes inadvertently. The study found that over 10% of the advertising payments received by these websites accounted for over $35.7 million spent on advertising on 11 sites between 2021 and 2024. Nonprescription wellness products were the most common type of health advertising found on websites promoting health information. Nonprofit health advocacy groups and the US Department of Health and Human Services also contributed to the study. The American Heart Association and Alzheimer's Association were among the nonprofit organizations with advertisements appearing on these websites. However, experts say the impact of these advertising on these sites is not immediately quantifiable.