At age 33, Nancy Davis was diagnosed with Multiple Sclerosis, and told there was nothing she could do about it. "I was given a very negative diagnosis that said my life was basically over and I would never be able to walk, I'd be confined to bed, that I was lucky because I'd be able to operate the remote control of my TV set!," she says.

It was a devastating moment. "I couldn't imagine living this life. I had three young children, I couldn't imagine not to be with them, not to teach them, not to educate them."

But instead of going home to wait for the disease to consume her, she says she went to get a second opinion. And that changed her life.

"As I got more and more second opinions, I got different information," she says. "You can't blame a doctor. You have to do your own research, do what you know in your heart is right to do. You know your reaction when you're diagnosed is not just to go home, pull the covers over your head, cry and feel very sorry for yourself. At the end of the day, that's not going to get you any better. I think you have time when you can do that, but then you've got to fight, you've got to be very strong."

Fourteen years later, Davis is not only still living a full and energetic life, she is helping others take control of their treatment. She has become a nationally recognized speaker about Multiple Sclerosis and founded the Center Without Walls, a national medical research organization. In her new book, Lean on Me, she talks about the important steps patients must take to gain control of their health and lives.

"You need to get a second opinion," she says. "You need to learn what the disease is, what your options are. You need to understand how insurance works, how you can get the best possible coverage for yourself no matter what, how to go to drug studies if there is no drug that exist for your particular ailment."

That's good advice, says Dr. Mehmet Oz, professor of surgery at Columbia University. Unfortunately, he says, most patients don't educate themselves about their diagnosis or their treatment options.

"Eighty per cent of people never ask for a second opinion, which is a big mistake," he says. "You'd never buy a car without getting a second opinion. The same holds true for getting a diagnosis from your doctor. One third of the time, those diagnoses are changed by what a second doctor may tell you."

But Dr. Oz understands why many patients are reluctant to seek a second opinion. "We're always embarrassed about telling our doctors that we want to see somebody else because we think that implies that we don't trust them," he says. "But I'm telling you right now as a specialist -- I do heart surgery -- I'm very proud when patients go get a second opinion because it means they want not just to check what I'm telling them, but they are going to bring me back information that's valuable to me. If they come back to me after getting a second opinion, it validates that I'm doing a good job."

In his book, You: The Smart Patient, Mehmet Oz recommends choosing a physician carefully, noting that the Internet has made it easier for patients to do that. And, he says, when you visit your doctor, be well prepared.

"When you go to see a doctor, make sure you have a list of questions written down," he says. "It's a simple thing to do but it makes a much more efficient discussion, which means the doctor will be more patient listening to your concerns. When you go in to speak with your physician, be clear about the facts, you know what your family history is, you know what your major risk factors are, and you're willing to be very honest with them."

Dr. Oz says smart patients do not usually go to their appointments alone. They take a spouse or a friend along, to help them understand the medical terms and make the right decisions.

According to Lean on Me author Nancy Davis, this "health team is what patients need, especially when they are diagnosed with a serious illness. "It's so important to be surrounded by positive people, and people that will help you," she says. "When you are diagnosed with something, you don't always hear what the doctor says correctly. I know I didn't. You're flooded with all these emotions. [It's important to have] somebody who is there for you, who can be very calm, very organized - you need somebody calm and organized - to go to the doctor appointments, to help prepare [you for] your x-rays, your questions you need to ask the doctors. It makes a big difference to have somebody with you."

That's very helpful not only for patients but for their physicians and the medical system as well. Mehmet Oz says when patients are aware of their influence, and well prepared and informed about their treatment options, they become partners in the process? and that leads to the best care.