Dementia is a growing global concern, but the good news is that we are making substantial progress in the fight against this disease. You wouldn’t know it from the prevailing paradigm: In the U.S., more than 6 million people are estimated to be living with dementia, and these numbers are widely projected to double in the next 25 years. Our recent research, however, challenges current predictions and calls for a reevaluation of the way we think about dementia’s future impact.
Our research at Duke University has introduced a critical revision to previous estimates of dementia’s future dominance. This revision represents a major paradigm shift in how we understand the trajectory of dementia, and it has important implications for public health policy and individual risk management. Our study found that over the past 40 years, each successive generation had lower dementia rates than their parents’ generation. This is unexpectedly good news, as it suggests we are making substantial progress in the fight against dementia.
Experts have projected a marked rise in dementia cases driven by an aging population: the so-called “silver tsunami.” The assumption has been that as the population ages, the number of dementia cases would grow proportionately. But our research uncovered a key flaw in prior studies: they failed to account for the “birth cohort” effect. This refers to the phenomenon uncovered in our research where each successive generation experiences lower rates of dementia at each age compared to their parents’ generation. Our finding is supported by studies in several other nations. This subtle, yet crucial, phenomenon could change how we approach dementia-related health care, research, and policy.
Rather than a looming “dementia epidemic,” we might be entering an era where dementia’s impact, while still significant, is less overwhelming than previously predicted.
What’s behind this unexpected trend? The answer lies in changes to key lifestyle and health factors. Over the past several decades, education levels have risen, smoking rates have fallen, childhood nutrition has gotten better, and the treatment of cardiovascular diseases and hearing loss have improved. These positive changes in health behavior may partly explain the decline in dementia rates. Nonetheless, we also point to rising rates of obesity, diabetes, and a sedentary lifestyle as emerging risks that could threaten to slow down or even offset these gains. Lowering diagnostic thresholds and developing new tests to detect early disease would also inflate numbers.
Read More: Changing Your Diet and Lifestyle May Slow Down Alzheimer’s
The dementia that is diagnosed at age 70 may begin around age 45. Research from our lab and others shows that silent build-up of brain plaques and mini-strokes begins years or even decades before memory loss, especially in those at genetic risk. So it’s never too early to begin a brain-healthy lifestyle.
Here are the habits that our research, and that of others, has revealed to be effective at keeping your brain healthy:
1) Monitor your body weight, blood pressure, cholesterol, and blood sugar through annual check-ups, and try to keep levels within normal range. What’s good for the heart is good for the brain.
2) Engage in physical exercise regularly. A walk a day may well keep dementia away.
3) Follow a brain-healthy eating regimen such as a Mediterranean diet or plant-based diet. Diets rich in legumes, vegetables, whole grains, unsaturated fats, nuts, fruits, and low-fat dairy products may slow brain aging.
4) Minimize your risk of head injury by wearing helmets when skating or biking.
5) Stay socially active. Loneliness raises risk for dementia.
6) Pursue mentally stimulating activities and challenge yourself cognitively through board games, crossword puzzles, and learning new skills.
7) Get 6–8 hours of sleep each night. Newer studies suggest sleep is crucial for strengthening memories, clearing toxins and boosting our immune system.
While we may not be facing the catastrophic dementia epidemic once anticipated, the rise of new risk factors means we must remain proactive. The fight against dementia is not over—but understanding its future trajectory will help us better manage the challenges ahead.
The post Why the Future of Dementia May Not Be as Dark as You Think appeared first on TIME.
