The owner of Safeway and other grocery brands is buying the drugstore chain Rite Aid as retailers continue to plunge deeper into health care and adjust to swiftly changing shopping habits.

Albertsons Companies executives said Tuesday that their purchase of Rite Aid's more than 2,500 remaining stores will help the combined company become a "leader in food, health and wellness."

The combination will have 4,892 stores and more than 4,300 pharmacies with a stronger presence on both coasts of the U.S. market. Leaders of both companies said the deal will help attract pharmacy customers who tend to s...