With corporate profit growth dwindling, stocks of mature companies that have track records of increasing dividends may provide a way to protect a portfolio against a possible downturn.

Just ask Donald Kilbride, the manager of the $38.6 billion Vanguard Dividend Growth Fund, which recently reopened to new investors after restricting access only to existing clients three years ago.

Steadily rising income from dividends has countered the risk of declining value in past markets. And over the long term — Mr. Kilbride took over the management of the fund in 2006 — the fund has performed solidly in rough and volatile markets.

“I feel more strongly about what we do today because I’ve just seen it work,” he said. “It powers through the hiccups.” In 2018, for example, when the S&P 500, with dividends, fell more than 4.4 percent, Vanguard Dividend Growth rose 0.18 percent. In 2008, when the S&P 500 lost 37 percent, including dividends, Vanguard Dividend Growth investors lost money, too, but much less: 26.6 percent.