Aug 15 (Reuters) - Nu Holdings Ltd on Monday reported second-quarter revenue that more than doubled as the Warren Buffett-backed digital banking firm logged strong customer growth in Brazil, Mexico and Colombia.

Nubank has managed to buck the downturn in the sector triggered by geopolitical turmoil, rate-hike fears and decades-high inflation on the back of its diversified product offerings ranging from credit cards to personal loans.

The lender said profitability from sustained performance in its domestic Brazilian market and robust demand for core products is supporting its international expansion in Mexico and Colombia.

Total revenue surged 230% to $1.2 billion for the quarter ended June 30. On an adjusted basis, the bank posted net income of $17 million.

Nubank's customers grew by 5.7 million, or 57%, in the quarter, to a total of 65.3 million, while clients for its core credit card products hit 29 million.

The company's 90 plus days non-performing loan ratio reached 4.1% in the quarter, in line with expectations.

The lender, which listed its shares in New York in December, has seen the stock shed half its market value so far this year against the backdrop of turbulent capital markets. (Reporting by Manya Saini in Bengaluru and Peter Siqueira in Sao Paulo; Editing by Shailesh Kuber)