They include five men and two women arrested on suspicion of crimes ranging from driving while unfit through drink or drugs to affray.
Among them was mother-of-four Sharmila Ullah who was being held at Bloxwich Police Station in July 2014 after being arrested for shoplifting.
A coroner concluded there had been some 'individual failings' in regards to observations while she was in custody but he was not satisfied they had contributed to her death.
Responding to the figures - which were released under the Freedom of Information Act - West Midlands Police said several 'safeguards' had been put in place in recent years.
They include the assessment and regular re-assessment of the health and mental wellbeing of those brought into custody, CCTV covering all public areas and some cells, routine safety reviews of custody facilities and training for custody staff.
Chief Superintendent Mark Robinson, Head of Criminal Justice Services, said: "Every death is an individual and family tragedy and a matter of deep regret.
"West Midlands Police has made great strides in creating safer detention spaces, which makes deaths in police custody extraordinarily rare.
"The welfare of those in our care is closely monitored by our own staff as well as members of the public who volunteer to serve as custody visitors, this is in addition to regular inspections by Her Majesty's Inspectorate of Constabulary and Her Majesty's Prison Service."
Of the seven deaths in the West Midlands, five were in cells across Birmingham, one in Walsall and one in Coventry.
A two-day inquest into the death of Sharmila Ullah, better known as Millie, heard she had had been taken to Walsall Manor Hospital from Bloxwich Police Station after suffering abdominal pain and vomiting.
She was assessed and given medication to ease her symptoms before being discharged back to custody. She was also examined by a nurse at the custody suite the following morning.
The inquest was told her condition had deteriorated and she was later found to be unresponsive in her cell. Paramedics were called and she was taken back to the hospital but efforts to revive her failed.
Her sudden death sparked an independent investigation by the Independent Police Complaints Commission (IPCC) which said she had been examined by nurses who said she was 'fit to detain' in a cell.
At the inquest, her family said they were concerned there had been a lack of communication and understanding between the hospital staff and police officers which may have contributed to her death.
But senior coroner Zafar Siddique said that post-mortem evidence suggested her sudden death had been due to long-standing alcohol misuse and alcohol withdrawal.