Aug 5 (Reuters) - Health and life insurer Aflac ( AFL )

on Tuesday beat Wall Street estimates for second quarter profit,

driven by steady premium gains in the United States offset

investment losses.

However, shares of the company fell 2.2% after the insurer

reported second-quarter revenue that declined from a year

earlier and missed analysts' estimates, weighed down by net

investment losses of $421 million.

Aflac ( AFL ) provides accident and pet insurance plans through its

units in the United States and Japan, as well as supplemental

insurance to help cover out-of-pocket costs, including

specialized coverage for critical illnesses, dental care, and

ophthalmological requirements.

The company's U.S. unit earned net premiums of $1.5 billion

for the second quarter, up 3.4% from a year earlier.

The insurer reported total revenue of $4.2 billion for the

second quarter, missing analysts' estimates of $4.33 billion,

according to data compiled by LSEG.

On an adjusted basis, profit for the quarter ended June 30

was $1.78 per share, beating analyst estimates of $1.70 per

share.

Aflac's ( AFL ) board declared a third-quarter dividend of $0.58 per

share, payable September 2 to shareholders of record as of

August 20.