Walking 5,000 steps per day delays cognitive decline

Walking 5,000 steps a day may delay cognitive decline by about three years, and 7,500 steps a day could slow it by seven years, says a new study published in Nature Medicine (November). The study analysed 296 adults aged 50-90 years, all of whom were mentally healthy at start. They were participants in a long-running Harvard Aging Brain Study. Brain scans were taken to measure two major protein buildups in the brain — amyloid-beta and tau — accepted as strong markers of Alzheimer’s disease. Researchers followed participants for 14 years.

“Lifestyle factors impact the earliest stages of Alzheimer’s disease. This suggests lifestyle changes may delay the onset of cognitive symptoms if we intervene early. This research study explains why some people show early signs of Alzheimer’s but do not worsen as quickly as others,” says Dr. Jasmeer Chhatwal, associate professor of neurology at Harvard Medical School.

Human brain develops in five different phases

A new research study published in Nature Communications (November) suggests that the human brain develops in a series of distinct phases, or “epochs,” as its architecture shifts and reorganises how we think and process information. In this pioneering research, neuroscientists at the University of Cambridge, UK, identified four major inflection points in the average brain’s lifespan — at ages 9, 32, 66, and 83 — each marking a transition into a period with noticeably different neural characteristics.

According to the study, human cognition does not simply rise, peak, and then decline. Instead, only the phase from ages 9-32 it manifests increasing neural efficiency. From 32 to 66, the brain’s structure remains relatively stable, a period researchers associate with plateaus in intelligence and personality. After age 83, however, the brain begins to rely more heavily on disparate regions as connections between them gradually deteriorate.

“These eras provide important context for what our brains might be best at, or more vulnerable to, at different stages of our lives. It could help us understand why some brains develop differently at key points in life, whether it is learning difficulties in childhood, or dementia in our later years,” says Dr. Alexa Mousley, a postdoctoral research associate at the Cambridge University and the study’s lead author.

Childhood hypertension has doubled in 20 years

Cases of high blood pressure among children and teenagers have nearly doubled worldwide during the past 20 years, according to a new study published in The Lancet Child & Adolescent Health (November). The study, which analysed data from 96 studies across 21 countries involving more than 443,000 children and adolescents, reveals that hypertension among pre-19s rose from around 3.2 percent in 2000 to over 6 percent in 2020. It also flagged a disturbing trend of “pre-hypertension” affecting 8 percent of children and teens and “masked hypertension” affecting over 9 percent of young people.

Researchers found that nearly 20 percent of children and teenagers with obesity experience hypertension, almost 8x the rate of children with healthy weight. According to study author Dr Peige Song, of Zhejiang University School of Medicine, the rise of hypertension is “driven largely by lifestyle factors such as unhealthy diets, decreased physical activity, and increasing prevalence of childhood obesity”. “Promoting healthy habits, such as a balanced diet rich in fruits, vegetables and whole grains while minimising salt and sugar intake, can substantially reduce the incidence of hypertension.

Gene mutation causes rare diabetes in children

Researchers from the University of Exeter (UK) and Université Libre de Bruxelles (Belgium) have identified a previously unknown form of diabetes that afflicts infants under six months of age. Typically, when diabetes develops this early, it is caused by a genetic mutation, say the researchers in a new study published in the Journal of Clinical Investigation (November). Using advanced DNA sequencing and innovative stem cell models, they discovered mutations in the TMEM167A gene, which is linked to a rare type of neonatal diabetes.

“Finding DNA changes that cause diabetes in infants provides unique insights to identify genes that are vital for insulin production and secretion. This discovery has helped to clarify the function of the little-known TMEM167A gene and revealed its key role in insulin secretion,” says Dr. Elisa de Franco, senior research fellow at the Exeter University.