Sharon Stone and Melanie Griffith on Keeping the Brain Healthy

But new research offers new hope, Maki said. "The fundamental shift in our understanding is what we can do to help ourselves. Keeping your heart health very strong is the best thing we can do at midlife."

Panelist Paula Wagner, Stone's former agent and the $3 billion producer of many Tom Cruise hits, warned women not to fall into the common Hollywood trap of thinking of yourself as a 25-year-old. “You will be older longer than you will be younger,” Wagner said. “Cherish the wisdom of older people.”

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Griffith joked that her divorce from Antonio Banderas "was the real healer for me," but she was quite serious about the health implications of stress and why we all need to address it. “I’m not stressed anymore," she said. "As women, we take on family, we get the husband, we have the life, we have the children, we take care of the house, we also go to work, we can’t sleep at night because we are up with the kids. I don’t think I’ve slept for 35 years."

Stone shared that the medical crisis cost her her marriage, custody of her child, and her career. "I know what it's like to go through a situation where you are the top, top, top of your field, to absolutely wiped out. A lot of it was simply because no one could look at me and simply understand that I was having a brain hemorrhage." Taking action turned her life around. "I now have custody of my child again. I’ve paid off my house again. I’m back in the black. Several months ago, I rehired managers and agents."

Posluns shared her recommendations of regularly engaging in exercise and sex, which improve brain health. “You’re never too young to start looking after your brain health,” Posluns said. And, of course, you're never to old to do so. Maki agreed: "Keeping our brains active in novel ways, such as learning a new language or a new skill. You need to exercise as well as keep your stress levels low. All of these things are associated with a lower risk of Alzheimer’s disease later in life."