When former President Jimmy Carter recently announced he had cancer, many people were impressed by his upbeat attitude and the strength of his religious beliefs.

“I’m perfectly at ease with whatever comes,” Carter said in a news conference the day after he had started his treatment regimen. “I do have a deep religious faith, which I’m very grateful for.”

We've long heard about the power of positive thinking, but can optimism and an encouraging outlook mean a better outcome for someone facing such a serious illness?

The experts have mixed views.

The power of joy

In a study of 34 women with breast cancer, clinical psychologist Dr. Sandra Levy from the University of Pittsburgh and National Cancer Institute oncologist Dr. Marc Lippman, found that women who reported feeling more joy in their lives lived longer than those women who said they were depressed.

"In other research we, as well as others investigators, also found that social support — friends, family, fellow church members and colleagues — also contributed significantly, not only to better mental health, but also possibly to more favorable disease outcome in cancer patients," Levy tells MNN.

Oncologist Dr. Barry Boyd has said that some preliminary studies have shown that how patients deal with stress may influence some cancer outcomes.

"For some individuals, I believe that we will identify hope and attitude as influencing tumor behavior," Boyd told CBS News.

"I think there is a part of attitude that may play a role, and we're still trying to understand that," said Boyd, who is the director of nutritional oncology for the Yale Health System. "Working to build hope and build optimism may, in some individuals, change the biology of their cancer."

person praying with hands on a wooden tableDoes being more spiritual help fight illness? (Photo: LoloStock/Shutterstock)

The impact of faith

For 30 years, Dr. Harold Koenig, professor of psychiatry and behavioral science at Duke University, has studied the connection between spiritual beliefs and health.

"Religious beliefs have positive effects across the board in terms of mental health in particular: enhancing well-being, reducing depression, developing social connections, producing a sense of purpose," Koenig, director of Duke's Center for Spirituality, Theology and Health, tells MNN. "And better mental health a lot of times translates into better physical health and often better coping with illnesses — such as cancer — as well."

Koenig is senior author of "The Handbook of Religion and Health" that documents some 1,200 studies about the effects of prayer on health.

"About two-thirds of those studies found that those who are more religiously involved, those who pray more, those who are more involved in religious communities do better mentally, physically and behaviorally."

Koenig points out that people who are more religious tend to be depressed less often and when they do become depressed — say from a serious diagnosis — they rebound more quickly than those with no spiritual leanings.

"It's a combination of the psychological benefits and the social and behavioral benefits of the religious involvement that affect physical health and provide an environment where healing is possible," he says. "We're not invoking anything supernatural going on or miraculous healing. That very may well occur, but that's not what we're studying."

The other side of the coin

One major study focusing on whether frame of mind impacts recovery was conducted by psychologist Dr. James Coyne of the University of Pennsylvania. He studied whether emotional well-being predicted survival in patients with head and neck cancer and found no connection.

He said the few studies that show a correlation between a positive mindset and a positive health outcome are "based on bad science."

"Attitude doesn't matter for survival," says Coyne.

Coyne tells the story of Dr. Margaret Watson, a psychologist at the Royal Marsden Hospital in Sutton, England, who did a preliminary study in the '70s that found that a "fighting spirit" contributed to a better survival rate in breast cancer patients. The study, says Coyne, was methodologically pretty weak, so Coyne and her co-researchers did a much larger study and this time found no association between having an upbeat attitude and surviving cancer.

"She said, 'I'm relieved because now we shouldn’t have to burden cancer patients with the attitude that they have to adopt a fighting spirit,' " Coyne explained to MNN.

In fact, when the later study was released, Watson said, the findings should erase "any burden of guilt'' for women ''who have difficulty feeling positive all the time.''

''I think it is important for women to feel that they should go on fighting,'' Watson said, ''but many women who have fought will very likely have times when they don't feel like it.''

Coyne agrees.

"We have to be careful about burdening cancer patients with the idea that they have more control over the condition then they possibly have," he says. "If they tend to organize their dealing with cancer as a fight and a fight that they can actually win, that's fine. But it won't affect their medical outcomes."

He says some of it is just an American attitude.

"It's a strong cultural belief in the United States: We want to believe 'mind over matter' and that mind can control illness, and it's tough to give up on that."

Better quality of life

The one thing experts seem to agree on is that even though some believe a positive attitude or spirituality won't encourage healing, it can make day-to-day living much more bearable for some people with serious illnesses.

"Being positive can make it easier for some people to deal with it," says Coyne. "But some people feel better if they get mad as hell."

There's no scientific proof that a positive attitude improves you chance of being cured, says Dr. Timothy J. Moynihan, a cancer specialist at Mayo Clinic, in Rochester, Minnesota. But he admits there is a benefit to an upbeat mindset.

"What a positive attitude can do is improve the quality of your life during cancer treatment and beyond," he writes on Mayo Clinic. "You may be more likely to stay active, maintain ties to family and friends, and continue social activities. In turn, this may enhance your feeling of well-being and help you find the strength to deal with your cancer."

people arm in arm looking at oceanDo support groups make it easier to deal with an illness, even if it just improves quality of life? (Photo: Claus Mikosch/Shutterstock)

Do support groups help?

Even the American Cancer Society has weighed in on the topic. According to the organization's website, "People with cancer and their families may feel guilty about their emotional responses to the illness. They may feel pressure to keep a good attitude at all times, which is unrealistic."

There's a section on the society's website that addresses attitudes and cancer. It discusses non-medical cancer treatments (typically some form of therapy or counseling) and the impact they can have on cancer:

Treatment that deals with our emotions and relationships (sometimes called psychosocial interventions) can help people with cancer feel more upbeat and have a better quality of life. But there’s no good evidence to support the idea that these interventions can reduce the risk of cancer, keep cancer from coming back, or help the person with cancer live longer.

Again, however, there's reference to how feeling better psychologically can help with quality of life.

"Still, things like group support, individual therapy, mindfulness, and relaxation techniques can be used to help reduce distress and cope with the emotions that come with a cancer diagnosis."

For his part, Carter is tackling his diagnosis with obvious optimism. He continues to teach his regular Sunday school classes and says he's ready for whatever happens.

“I’ve had a wonderful life, I’ve had thousands of friends, and I’ve had an exciting and adventurous and gratifying existence.”

Mary Jo DiLonardo Mary Jo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.