Where Does Calendula Have the Strongest Evidence?

Calendula is particularly interesting because its strongest human evidence concerns something it has traditionally been associated with for generations: the skin and wound healing.

Clinical studies have investigated calendula creams and ointments for several types of skin damage and wounds. A large randomized trial involving women receiving radiotherapy for breast cancer found that calendula ointment reduced more severe radiation-related skin reactions compared with another topical treatment. However, another clinical trial found no advantage over standard skin care, showing that results are not entirely consistent.

Calendula extract has also produced promising results in a study of venous leg ulcers, where wounds treated with calendula healed more rapidly than those in the control group. Another randomized study found that calendula ointment reduced pain and improved signs of wound healing after episiotomy.

There has also been research into calendula preparations used locally inside the mouth for inflammation associated with cancer treatment.

By comparison, there is much less high-quality evidence for taking calendula orally, and most research on calendula essential oil remains laboratory or preclinical research rather than human clinical trials.