While there’s no sure way to prevent dementia, strong evidence shows that a healthy lifestyle can significantly reduce your risk of cognitive decline as you age. A healthy diet is one of the best ways to lower your dementia risk—and a new study reveals how a deficiency in one particular nutrient can lead to an increased risk of dementia. Read on to find out what it is, plus how you can ensure that you get enough of it to protect your brain. READ THIS NEXT: Doing This at Night May Help You Ward Off Dementia, Study Says. Dementia is an umbrella term that is not defined by a single illness. Rather, the condition refers to a group of diseases that impair your ability to remember, communicate, think clearly, concentrate, and make decisions. These include vascular dementia (brain damage caused by reduced blood flow to the brain, typically following a stroke), Lewy body dementia (mobility problems such as poor balance, trembling, and stiffness), Parkinson’s disease, and Huntington’s disease.ae0fcc31ae342fd3a1346ebb1f342fcb Dementia manifests in in a number of ways, and early signs may include depression, hearing loss, dry mouth, and vision changes. That’s why it’s imperative to know the early signs of dementia, so you can spot them if they appear and get treatment as soon as possible. READ THIS NEXT: If You Do This During the Day, It May Be an Early Sign of Dementia. Many risk factors are associated with cognitive decline, including age, genes, ethnicity, heart health, previous brain trauma, and lifestyle. However, improving your diet and lifestyle can significantly reduce your dementia risk. In addition, a healthy lifestyle can help ward off other risk factors for dementia, such as heart disease, stroke, and diabetes. Eight out of 10 Alzheimer’s patients have insulin resistance, a metabolic condition caused by poor diet and a sedentary lifestyle. According to the University of North Carolina, approximately 88 percent of U.S. adults have some degree of metabolic illness, putting them at a much greater risk of chronic conditions like cardiovascular disease and diabetes—two significant risk factors for developing dementia. An April 2022 study published in The American Journal of Clinical Nutrition found a direct link between dementia and a lack of vitamin D. Examining the association between vitamin D and cognitive decline, the researchers found that low vitamin D levels were associated with lower brain volumes and a higher risk of dementia and stroke. The researchers found that in some populations, as many as 17 percent of dementia cases could be prevented simply by getting adequate vitamin D. “Vitamin D is a hormone precursor that is increasingly recognized for widespread effects, including on brain health, but until now it has been very difficult to examine what would happen if we were able to prevent vitamin D deficiency,” Elina Hyppönen, the director of the Australian Centre for Precision Health and one of the study’s lead authors, said in a statement. For more health news sent directly to your inbox, sign up for our daily newsletter. Vitamin D is an essential nutrient that plays a vital role in bone development, tooth health, and immune function. As we age, vitamin D deficiency becomes increasingly common, reports the Mayo Clinic, partly due to the skin’s decreased ability to synthesize vitamin D from the sun. Spending time outdoors, eating foods that contain vitamin D, and taking a vitamin D supplement can all help slash your dementia risk. According to the National Institutes of Health, adults 70 and younger need 600 international units (IU) of vitamin D daily, while adults over 70 need 800 IU daily. Speak with your healthcare provider before taking a vitamin D supplement to determine your best options. Although the evidence points to a link between dementia and vitamin D deficiency, more studies are needed to determine if a lack of vitamin D is a risk factor for cognitive decline. “More research is needed, including intervention studies to determine if stabilizing vitamin D levels would benefit dementia risk reduction,” says Heather Snyder, PhD, vice president of medical and scientific relations at the Alzheimer’s Association. “The body and brain are closely connected, and it’s important to take care of your overall health and well-being—including vitamin levels throughout your life and especially as we age. Talk to your doctor if you have any concerns regarding your health, including any memory concerns.”