Clashes are erupting in statehouses, churches, hospitals, and newsrooms across America as scientists and people of faith debate the value of vaccinations, access to contraception, and whether or not a person’s sexuality can be changed.

When the Republican Party of Texas recently endorsed reparative therapy to treat homosexuality, it was the latest salvo in an increasingly public debate between clinicians and people with strong religious convictions.

Most prominent medical organizations in the U.S. have gone on the record saying that reparative therapy does not work and can even be psychologically harmful.

Though gay couples can marry in 19 states and the District of Columbia, and generally enjoy a climate of acceptance, many people behind the Tea Party-led resolution said that it reflects their faith and family values.

Jonathan Saenz, president of the group Texas Values, told the Associated Press: “The platform reflects what the people in the Republican Party have asked for, and that should be no surprise: family values, protection of marriage between one man and one woman, and everything that goes along with that.”

Religious beliefs and the tenets of medical science have come into conflict in other arenas as well, including debates about childhood vaccinations, blood transfusions, and access to contraception.

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Gayle Woloschak, Ph.D., a scientist at the Feinberg School of Medicine at Northwestern University in Chicago, also serves as associate director of the Zygon Center for Religion and Science in Chicago. A religious person with an Eastern Orthodox background and a degree in ministry, she told Healthline that U.S. politics has entered phase in which “it’s politically expedient to deny science and medicine.”

She said these views are driven by ideology. “When George [W.] Bush stands up and says he doesn’t believe in evolution, that is a medical issue. Where do we test our drugs? Do we test them on goldfish? We test them on monkeys, because they are closer to us on the evolutionary ladder.”

Bush made these remarks as president in a December 2008 interview on ABC’s Nightline.

In some cases, people may be misinterpreting their own religious doctrines, according to an analysis by nationally recognized scientist John Grabenstein, who works for the pharmaceutical company Merck. Grabenstein’s study showed that most mainstream religions do not oppose vaccinations, despite the claims of some of their members. His research was published last year in the journal Vaccine.

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Some religions do have core beliefs that are opposed to elements of medical science, independent of the current political climate. For example, Christian Scientists do sometimes oppose vaccinations, Grabenstein said. And members of the Jehovah’s Witnesses have long opposed blood transfusions.

Dr. Amy Baxter, an Atlanta pediatrician, told Healthline that this belief can be very dangerous. African-American patients are at greater risk for sickle cell anemia, she said, and many African Americans are also Jehovah’s Witnesses. “This is one we run into all the time in the emergency department,” she said. “Sometimes patients will auto-donate before surgeries, but sickle cell patients don’t have blood to do that when they need transfusions.”

Dr. Amesh Adalja, a biosecurity expert and critical care professor at the University of Pittsburgh Medical Center, has been in situations where patients decline blood transfusions. “It comes to the point sometimes where you have to ask the person to think about their commitment they have to their religious beliefs,” he told Healthline. “I have heard of instances were religious readers come in and absolve them to allow them [to have the treatment].”

A movement against childhood vaccinations is also surfacing in the U.S. and parts of Europe, and Adalja said that opposing immunizations on religious grounds “is something that gains traction and disarms physicians and public health officials.”

He noted that some U.S. states are closing loopholes that allow for vaccine exemptions for children attending public schools. Still, cases of vaccine-preventable whooping cough have reached “epidemic” proportions in some states, including California.

David Ley, Ph.D., a New Mexico psychologist and author of the book The Myth of Sex Addiction, told Healthline that moralistic views of sex, which are not based on science, are fueled by the fact that sex education is barely taught in medical school, and even less so in training for psychologists. The result is an acceptance of those who aim to control sexual behavior. But sex is normal, he argues, and is different for everyone.

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Fears about sex are fueled by the social freedoms that people now enjoy, Ley said. “Our ability to control people’s sexual expression and sexual desire is diminishing.”

Ley operates a mental health and substance abuse clinic in Albuquerque, N.M. He said that anti-addiction programs fueled by religious practices can be dangerous. “They think their positive intent absolves them from the requirement to be objective,” Ley said. “Those values, when they creep into issues of mental health diagnoses and treatments, there is a tremendous risk of bias and damage.”

In some states, pharmacists and other healthcare providers can refuse to provide contraception on similar grounds. Battles are being waged in statehouses nationwide over these standards, known as conscience clauses. The idea is to give healthcare providers a way out when they are asked to prescribe something that violates their personal, moral, or religious beliefs.

“Some women who become pregnant can die,” Woloschak said. She recalled a woman she knew who had lupus, an autoimmune disease, and became pregnant. She chose not to have an abortion, and she died, Woloschak said. Other times, women need contraception for reproductive problems not related to preventing pregnancy.

A legal case brought by Hobby Lobby craft stores, challenging the provision of the Affordable Care Act that requires large businesses to provide contraception to their full-time employees, is currently before the Supreme Court.

What needs to happen, said Woloschak, is more dialogue. That is the mission of the Zygon Center. “Dialogue is no good if it doesn’t include scientists, pastors, theologians, and other mixes of people … If you can pull scientists into the discussion, and physicians and pastors from multiple different faiths … it’s sort of an academic approach that opens itself up to a broad community and stands a chance to be useful.”

In a personal note at the end of his paper on religion and immunizations, Grabenstein made a similar observation: “The coming together of public health and religion is not a collision; rather it involves repeated intersections. We can advance both healthcare and our own condition by discussing them more openly more often.”

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