Medical Expense

I have about $50,000 AGI, and about $70,000 of medical expenses.

Why does TurboTax insist on using the standard deduction for me, saying it is better than itemizing?

Here's the TurboTax message:

Your $70,402 medical expense deduction doesn't count yet because your tax due already includes the best tax break, which is the $27,400 Standard Deduction.