A Flight Attendant reported flight attendants became ill during the flight due to possible cabin fumes exposure.

Narrative

Roughly 1.5hr into flight multiple flight attendants became ill.Symptoms-Shortness of BreathHeadachesDizzinessMental fogTingling of fingertipsPurser contacted the flight deck and notified them and they contactedmedical advisory service due to WiFi issues.Medical advisory service suggested the crew had food poisoning even though none of the crew ate the same things or together- also symptoms didn't correlate with food poisoning.Purser paged for a medical professional- Dr responded. He is a cardiologist. He evaluated Purser; FA 1; AND FA 2 - blood pressure; pulse ox; listening to lungs/heart; simple neuro exam...He came to the conclusion that the crew with the symptoms above displayed symptoms of toxic fume exposure; whether carbon dioxide or carbon monoxide.FA 1; FA 2 ; and Purser were on oxygen (POB) (Portable Oxygen Bottle) for varying times intermittently.FA 1 and Purser smelled odors intermittently of dirty socks or locker room type of smell.All of the above information was communicated with the flight deck and then onward to medical advisory service; which came back with the updated recommendations of oxygen therapy; Tylenol; and anti-nausea meds.The flight continued to ZZZ; symptoms were about the same throughout the flight coming and going.Upon landing purser decided to have a standby traveling flight attendant take a jumpseat for landing and assume responsibilities. Standby FA 3 assisted the crew.At the gate in ZZZ; the flight was met by ZZZ paramedics. Evaluated the crew and their vital signs. The aircraft was also met by Maintenance personnel who interviewed the crew about their observations. Maintenance concluded the aircraft would be taken out of service and investigated.