Which statement about the effects of cupping therapy is true?

Cupping therapy is known to create temporary marks on the skin where the cups are applied, often resembling circular bruises. These marks result from the suction created within the cups, which increases blood flow to the area and can break small blood vessels, leading to these visible signs. Generally, these marks are harmless and subside after a few days. This effect is one of the more common responses to cupping therapy, making this statement accurate.

Additionally, while other statements in the question bring up important points about cupping therapy, they do not align with established facts. Cupping is not universally effective for all medical conditions, as its efficacy varies by individual and condition. Furthermore, like any therapeutic method, cupping therapy can have side effects, including pain, redness, and occasionally blistering. Lastly, a consultation before starting cupping therapy is important in order to assess the individual's health status and any contraindications, making the idea that it should always be performed without consultation misleading.