We’ve all heard the old wives’ tales. Deodorant will give you breast cancer and so do microwaves and tight-fitting bras.

Alas, all of these tales are fictitious. And unfortunately, there are a lot of other seemingly believable myths on breast cancer floating around, doctors say.

Many women, for example, have been told that women under the age of 40 should be getting mammograms and it’s the greedy insurance industry that is preventing them from doing so.

Mammograms, however, are ineffective for most young women, which is the real reason why they are discouraged from getting them, said Dr. Diana Zuckerman, president of the National Research Center for Women & Families.

“Young women’s breasts are dense and if they get mammograms, their breasts show up very white on mammograms and cancer shows up as white,” she said. “But, as women get older, their breasts are less dense and show up gray on a mammogram, which makes it easy to identify the white cancer. If there is a family history, and women are worried, they can start earlier and in this case a digital mammography may work better than a traditional mammography.”

Here are five other myths about breast cancer:

There's no history of breast cancer in my family so I won’t get it.

“That’s not true,” said Dr. Marisa Weiss, an oncologist and the president of breastcancer.org. Although women with a family history are at a higher risk for the disease, environmental factors, drinking, smoking, medication and diet can all influence a woman’s chances of getting breast cancer.

Knowing the history of breast cancer on both sides of your family is also important. Just because a woman doesn’t have a history of breast cancer on her mother’s side, doesn’t mean she’s at a decreased risk. A paternal family history of breast cancer also increases a woman’s chances of getting it.

I have breast cancer, so I have to get a mastectomy if I want to stop the spread and prevent the cancer from coming back.

Very few women diagnosed with breast cancer actually need a mastectomy, said Zuckerman. “In fact, most of the women who get mastectomies don’t need them,” she said. “And for women to lose their breasts, in addition to the normal emotional turmoil that they go through having breast cancer, is harmful emotionally and physically.”

Specifically, Zuckerman said that about 75 percent of the women who get breast cancer each year will not need mastectomies. Many women with stages 0, 1 or 2 breast cancer respond well to treatment that includes a lumpectomy with radiation and chemotherapy, she added.

"Women with early stage breast cancer usually do not need a mastectomy and will benefit from chemotherapy almost always," said Zuckerman. "Women who get a lumpectomy will need radiation and that's the difference. Women who get a mastectomy will not need radiation, but with a lumpectomy you always need radiation."

Young women are just as likely to get breast cancer as older women.

Both Weiss and Zuckerman agree that this also is not true. Women older than 50 are most at risk for this disease, explained Zuckerman.

“Breast cancer in women younger than 30 is so rare, and this is one of the things that concerns me,” she said. “I think the media focuses on young women, because it’s so shocking when someone in their 20s gets cancer. But what you end up with are women in their 20s and 30s who are terrified that they're going to get cancer and women in their 50s who think they don’t need to worry about it, when the opposite is true."

Of the nearly 200,000 women who will get breast cancer next year, half will be over the age of 61, said Weiss. About 25,000 women will be under the age of 40.

“It’s still a significant number, but when you compare it to the overall number of women who get breast cancer, it’s a small percentage,” she said.

Breast cancer is fatal.

“Breast cancer is not fatal in and of itself,” said Zuckerman. “What makes it fatal is if it goes into other parts of the body and gets into the lymph nodes, lungs and other organs,” she said.

“Also if it gets into the blood or the bones, it can kill a person. That’s the risk of metastasized cancer. That means it has spread and once it hits the lymph nodes, it can become out of control.”

Zuckerman said early detection is the best way to prevent cancer from spreading.

Men don’t get breast cancer.

“This is certainly not true,” said Weiss. “Men do get it.”

The American Cancer Society estimates that about 2,030 new cases of invasive breast cancer will be diagnosed in men this year, and about 450 men will die after getting the disease.

Still, breast cancer is about 100 times more common in women, and women whose fathers are diagnosed with breast cancer are at an increased risk for the disease just as they would be if their mothers are diagnosed with it, added Weiss.