It turns out that vitamin D is important for more than just strong, healthy bones.A new study out of Emory University found that taking vitamin D supplements may benefit brain health, particularly in older adults with mild cognitive decline.The research was published in the journal “Sleep Medicine.” The small study looked at 54 adults with early signs of dementia — specifically sleep issues and mild cognitive impairment — and found that those who took daily high doses of vitamin D (at least 5,000 IU) had better cognitive function when compared to adults who didn’t take the supplement. “In older adults experiencing both sleep disturbance and mild cognitive impairment, this may represent a critical window for intervention, when cognitive changes are emerging, but opportunities to support brain health may remain,” study author Victoria Pak said in a press release.Researchers had participants take the Montreal Cognitive Assessment, which is a dementia risk screening tool that measures thinking and memory. Participants who took 5,000 IU of vitamin D scored roughly 13% higher on this assessment than those who did not take vitamin D at all.There are limitations to this research, namely that the study is very small, so it’s hard to say if these results would hold up in a larger population. But the data does add to existing research that suggests vitamin D supplementation is important for brain health. Previous studies have found that low vitamin D levels may put folks at higher risk of Alzheimer’s disease and dementia. This is even true for adults in their 30s and 40s; other evidence suggests that high vitamin D throughout midlife resulted in fewer dementia risk factors as people aged.The research also only examined participants with two main symptoms of dementia ― sleep loss and mild cognitive impairment (which is defined as a slight decline in thinking and memory skills that appear to be worse than normal aging). Other red flags, like mood changes, were not analyzed as part of this study.Vitamin D supplementation won’t eliminate your risk of dementia entirely, but this study suggests that it’s one way to help slow down cognitive decline as you grow older.“Identifying accessible and modifiable factors, such as vitamin D supplement intake, during the earlier stages of cognitive decline may become increasingly important, particularly as rates of Alzheimer’s disease continue to rise,” Pak continued in the press release.Researchers found that the favorable cognitive effects occurred when study participants took either kind of vitamin D — vitamin D3 or vitamin D2 — but there weren’t memory or thinking improvements when someone took less than 5,000 IU of vitamin D.Eleganza via Getty ImagesOlder adults with mild cognitive impairment who took high doses of vitamin D scored better on a memory and thinking assessment.We typically get vitamin D from sunlight, supplements and certain foods, such as mushrooms, fatty fish, milk, egg yolks and more. But roughly 40% of American adults are vitamin D-deficient or insufficient. Beyond dementia risk, low levels of vitamin D are also a risk factor for cardiovascular disease ― and cardiovascular disease puts folks at heightened risk for dementia. “For vitamin D specifically, adding in healthy protein sources, particularly fatty fish such as tuna, salmon, sardines and mackerel, can be beneficial,” Dr. Thomas M. Holland, physician-scientist and assistant professor at the Rush Institute for Healthy Aging at Rush University Medical Center in Chicago, previously told HuffPost.“For overall brain health, incorporating foods such as dark leafy greens (i.e., kale, romaine lettuce, and spinach), berries (such as blueberries, strawberries, and blackberries), whole grains (like oatmeal, brown rice, and quinoa) and extra virgin olive oil is helpful, as these foods provide beneficial fatty acids and a wide range of supportive nutrients,” Holland added.Supplements including vitamin D can interact with certain medications and aren’t suitable for everyone, which makes it important to talk to your doctor before starting any new regimen.Researchers noted in the study’s conclusion that the findings are helpful in addressing memory loss and cognitive decline in the early stages, especially as more and more Americans are expected to receive dementia diagnoses in the coming years. Cases of dementia are expected to double by 2060 due to the aging population in the country, along with health habits (such as diet and exercise) and genetics.Beyond potential vitamin D supplementation, there are more lifestyle habits that can help lower (but not eliminate) dementia risk. These include controlling high blood pressure, managing or preventing diabetes, exercising, staying socially connected with loved ones, eating a diet that’s high in whole grains, fruits, vegetables and lean meats, challenging your brain with new activities like a new language or hobby, getting enough sleep each night and treating hearing loss.Whether or not you develop dementia is not fully in your control, but practicing these healthy habits can help reduce the chance of developing it or slow the development of cognitive impairment.