According to Live Science, a few possible side effects include heart palpitations and shakiness; however, there is not enough research or reliable information on the impact of raspberry ketones on the human body. WebMD adds that there is no telling what kind of long-term impact ketones can have on health or how they interact with other medications.
WebMD points out that most side effects of raspberry ketones are based on anecdotal reports. These reports mention increased blood pressure, a rapid heartbeat and jitteriness. Although there is no concrete evidence to prove the efficacy of ketones, people use them as a weight loss supplement. One study followed a group of people over four weeks who took 1,200 milligrams of vitamin C and 200 milligrams of raspberry ketones per day. Although the study found that the participants experienced weight loss, it is unclear whether this occurred due to the vitamin C or the raspberry ketones.
According to WebMD, raspberry ketones are chemicals found in raspberries, which give the fruit their signature smell. Besides weight loss supplements, they are used in a variety of products to add their particular raspberry flavor and aroma to cosmetics, foods and beverages. Although they are generally deemed safe when found in food, it is best to consult a doctor before taking raspberry ketones in pill form.