t’s the age-old Question- Nature versus Nurture.
We often question whether our environment or our genes has the greater impact on the developing of certain diseases. Thanks to a report published in July in the Journal of the American Medical Association (JAMA), there is greater evidence that we can reduce our risk of developing dementia by living a healthy lifestyle. This study was conducted by researchers from the United Kingdom, USA, Australia and Germany and looked at 196,383 adults aged 60 or over who did not have dementia when they were recruited, and who had provided DNA samples. They then looked at the DNA of these volunteers for known genetic risk factors for Alzheimer’s dementia and ranked them as high, medium or low risk.
They also looked at self-reported lifestyle choices and classified healthy behaviours as:
✔ Not actively smoking.
✔ Regularly physically activity
✔ Healthy diet (high in fruits vegetables and low in processed grains and meats)
✔ Moderate alcohol consumption – an average up to 1.75 drinks a day for women and up to 3.5 drinks a day for men.
Again, based on these factors, they were grouped in healthy, average and unhealthy lifestyle categories. After 8 years, 0.9% of people developed dementia. The highest incidence was in the group with the greatest genetic risk (1.2%) and lowest in those with the least risk (0.6%). What is interesting is that when looking within each group, those with the healthiest lifestyles were less likely to develop dementia. In the high genetic group, if you had an unhealthy lifestyle your risk was 1.8% and if your lifestyle was healthy, this dropped to 1.1%. Overall, this meant a 32% reduction in the risk of dementia!
Now, the study did have some limitations-first of all, it only looked at European people so may not apply to all ethnicities. Secondly, since the people are volunteers, they may not represent the population as a whole. Lifestyle was measured at the start of the study and was self-reported so it is possible that lifestyles may have changed over the 8 years.
Regardless of the limitations, it is encouraging that lifestyle choices may reduce our risk of dementia.
Another study in the journal JAMA Neurology also published last month looked at whether having an active mind over a lifespan might also help reduce symptoms of dementia. The theory known as “Cognitive Reserve” (CR) suggests that stimulating the brain in early and middle age gives a reserve which may make a person more resilient to dementia. The researchers assigned a CR score based as education and mind-challenging activities such as reading and writing as well as social factors such as socializing friends and family. 1600 people were assigned a CR score and followed for 6 years. Those with the highest CR scores had a 40% reduction in dementia risk!
So my advice is to dust off that exercise equipment, trade the cocktail for a mock-tail, read a book (or write a monthly article for your local paper or magazine) and as always, take care of yourselves and each other.