is something that many people are constantly trying to achieve, but as you have indicated, it usually doesn't happen quickly without any significant changes in diet or activity level. Since sudden weight loss can be a sign of a more significant underlying medical issue, it is a good idea to see your primary care physician
for a more thorough history and physical exam. You are right that tapeworm infections can lead to sudden weight loss, but such infections are usually associated with other gastrointestinal symptoms. In addition, you would have to have acquired the tapeworm from somewhere, and unless you have been eating raw fish, beef, or pork without appropriate hand hygiene, tapeworm infections are relatively rare. However, there are several other medical conditions that can lead to sudden weight loss, including some cancers (also typically associated with other symptoms, including fevers and night sweats which your physician will undoubtedly ask you about); hyperthyroid disease (easily evaluated by checking your levels of thyroid hormone); celiac disease (again, likely to be associated with other gastrointestinal symptoms); or even diabetes. Your physician will likely want to do some basic blood tests along with your exam to make sure that any potentially serious medical problems are identified right away.