WASHINGTON, D.C. -- In a year when the movement for same-sex marriages continues to make strides across the U.S., Americans remain divided on how people come to be gay or lesbian. More than a third of Americans (37%) believe people become gay as a result of factors such as their upbringing and environment, while 42% say people are born gay. This latter belief is down slightly from 2013, when nearly half (47%) believed people were gay at birth.

These results are from Gallup's annual Values and Beliefs poll, conducted May 8-11. Americans' views on this question have evolved over time. When Gallup first asked about the origins of same-sex orientation in 1977, over half of Americans (56%) attributed it to an individual's upbringing and environment, while 13% believed it to be something a gay person is born with.

This gap in opinions narrowed over the time, and by 2001, Americans were more likely to believe in homosexuality as occurring at birth (40%) for the first time, though only by one percentage point. Since then, Americans have been roughly equally divided over this question, although with some year-to-year fluctuations in the precise percentages. Although this pattern appeared to be changing last year, when the belief that people are born gay rose to an all-time high of 47% after a slight increase in 2012, this year's slight downtick in the "born with" belief, halted the trend.

The scientific community does not agree on one unified viewpoint regarding the issue of a person's sexual orientation. According to the American Psychological Association, "there is no consensus among scientists about the exact reasons that an individual develops a heterosexual, bisexual, gay, or lesbian orientation."

An Increase in the Upbringing and Environment Belief Across Demographics

Though the plurality of Americans believe that being gay is present a birth, there continues to be large differences in perspectives across demographic, religious, and political dimensions. Those with college educations, whites, females, liberals, Democrats, high-income earners, and those who seldom or never attend church are the most likely to believe that being gay or lesbian is something people are born with. Most of these differences among the various demographic groups were evident in previous years, with nonwhites' belief in the upbringing and environment theory substantially higher this year than last year.

Bottom Line

The contention on this question of a person's sexual orientation possibly reflects a lack of input from the scientific community, which historically has not shied away from offering its opinion on lesbian, gay, bisexual, or transgender (LGBT) issues and questions. The American Psychiatric Association removed homosexuality from its manual of mental disorders in 1973, giving credence to the nascent gay rights movement at the time.

U.S. public opinion about gays has changed drastically in recent decades on the issues of marriage equality and LGBT acceptance as a whole, possibly related to the fact that three in four Americans say they have a friend, relative, or coworker who has told them that he or she is gay. Though being gay as the result of genetics or other factors before birth has become a considerably more mainstream belief and is now mentioned by a plurality of Americans, it is still one held by slightly less than half of the U.S. population. This disagreement seems likely to continue as long as the scientific community remains agnostic about the question.