As dementia forces former U.S. Supreme Court Justice Sandra Day O'Connor to withdraw from public life, she joins millions of Americans coping with brain changes that strike women more often than men.

"Some time ago, doctors diagnosed me with the beginning stages of dementia, probably Alzheimer's disease," O'Connor, 88, wrote Tuesday in a letter addressed to the public.

"While the final chapter of my life with dementia may be trying, nothing has diminished my gratitude and deep appreciation for the countless blessings in my life."

O'Connor, the first woman to serve on the Supreme Court, wrote that she wanted to be open about the changes in her health "while I am still able." Her husband, John O'Connor, lived with Alzheimer's for almost 20 years until his death in 2009.

"We commend Justice O'Connor for bravely sharing her diagnosis and increasing awareness about this devastating disease," the Alzheimer's Association said in a statement. "Justice O'Connor has been an advocate for caregivers and people living with the disease."

The Alzheimer’s Association predicts the prevalence of Alzheimer's could triple by 2050. It currently impacts about 5.7 million Americans and remains the sixth leading cause of death, killing more people each year than breast cancer and prostrate cancer combined.

Alzheimer's actually starts in the brain 20 to 30 years before the first symptom of memory loss, said Dr. Richard Isaacson, who runs the country's first Alzheimer's prevention clinic at NewYork-Presbyterian/Weill Cornell Medical Center.

If you are a woman, you have a greater probability of developing Alzheimer's than a man: women make up two-thirds of Alzheimer's cases.

The reason why may lie in part to a hormone that has a huge impact on a woman’s health: estrogen. It protects the body from many diseases, and when stores of it dip — as they do when a woman enters menopause — our organs, including our brain, may act against us. Despite this knowledge, the debate over hormone replacement therapy (HRT) and all of its pros and cons rages on. Is it the only way to protect our mind and memory, or can diet play a role?

Several studies indicate supplemental estrogen may in fact protect the brain from adverse changes associated with dementia and Alzheimer’s disease. A 2017 study in the journal Neurology found women who began HRT at the beginning of menopause had a decreased risk of Alzheimer's a decade later. Other studies indicate women on HRT have better working memory and lower early mortality. Futher, studies show postmenopausal women who take estrogen have a better brain structure and lower risk of dementia. The argument for embracing HRT to protect your brain is a compelling one, but it’s just the beginning. Other lifestyle factors (and genetics) play a strong role as well.

Can we get estrogen from our diet?

Hippocrates once said, “Let food be thy medicine.” Many of my postmenopausal patients embody this concept when they consider their brain health and their corresponding dips in estrogen. Often times, I see them adding estrogenic foods into their diet. These foods actually mimic estrogen in the body and include:

soy

some legumes, such as chickpeas and fava beans

flaxseed

sesame seeds

some cruciferous vegetables, such as kale and broccoli

apricots

oats

The key is to consume these foods in their whole form as opposed to something made in a food factory. That means your protein bar with soy isolates or that corn chip with flaxseeds in it doesn’t count. A 2017 study found whole soy sources could help to reduce the risk of death in women with certain breast cancers and could also help avoid brain alterations associated with Alzheimer’s disease. Like HRT, though, even these foods may be problematic for some women with certain types of breast cancer and can still be a controversial approach to improving brain health.

Whether you take the HRT route or choose a more natural option, your overall dietary and lifestyle factors are perhaps the most powerful component to protecting your brain. That’s because the typical Western diet, complete with plenty of red meat (including processed options like bacon, sausage and hot dogs), sugar, stripped grains, ultra processed “food like” items and the accompanying couch potato lifestyle may play a much larger role in predicting your chances of developing dementia and Alzheimer's.

A proven method to protect our brains

In 2015, an eating plan referred to as the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet emerged as a way to lower the chances of an Alzheimer's diagnosis. The amazing aspect was that benefits to the brain could be seen even when strict adherence to the diet did not occur. One study found the MIND diet lowered the risk of Alzheimer's by as much as 53 percent with strict adherence, and by about 35 percent with moderate adherence.

"Your overall dietary and lifestyle factors are perhaps the most powerful component to protecting your brain"

Components of the MIND diet surround the inclusion of brain-healthy foods such as berries, nuts, green leafy vegetables, beans, whole grains, olive oil, fish, moderate wine consumption and poultry; and the exclusion of foods that may promote the disease such as red meat, sugar laden foods, high-fat dairy and fried foods.

The brain loves blueberries and exercise

In addition to following the Mediterranean-DASH approach, adding in extra blueberries and a regular exercise routine will also go a long way. Anthocyanins in blueberries have been found to help delay cognitive decline and improve overall brain function. When you’re done downing your blueberries, lace up your tennis shoes. A 2018 study in the Journal of Alzheimer's Disease found the lack of exercise sped up the deterioration of important nerve fibers in the brain, which resulted in weaker white matter and lower brain function.

The mystery continues over why some people get Alzheimer’s and others don’t. But we do know this: it’s impacting women at an alarming rate and diet plays a role. Discussing your options with your physician is the first step, but in the meantime, cleaning up your diet, and moving more will surely have a positive impact.

Kristin Kirkpatrick, MS, R.D., is the manager of wellness nutrition services at the Cleveland Clinic Wellness Institute in Cleveland, Ohio, and the author of "Skinny Liver." Follow her on Twitter @KristinKirkpat.