A study published in the British Medical Journal suggests the brain’s abilities begin to decline as early as age 45, BBC News reported. Previously, scientists had thought that cognitive decline does not truly begin before age 60, according to BBC News.
"We were expecting to see no decline, based on past research," Archana Singh-Manoux, who led the research team, told Reuters. "It doesn't suddenly happen when you get old. That variability exists much earlier on. The next step is going to be to tease that apart and look for links to risk factors."
Over a 10-year period, researchers at University College London tested about 5,100 men and 2,200 women between the ages of 45 and 70 on memory, vocabulary, hearing and visual comprehension skills, Fox News reported. They found a 3.6 percent decline in mental reasoning in women and men ages 45 to 49, Fox News reported.
Older people’s mental reasoning abilities declined more, the study found, according to Fox News. There was a 9.6 percent decline in the abilities of men ages 65 to 70 years at the start of the study, and the abilities of women in that age group declined 7.4 percent.
Not all study participants experienced “senior moments.” One-third of all individuals in the study showed no deterioration over the period, Reuters reported.
According to Reuters:
Pinpointing the age at which memory, reasoning and comprehension skills start to deteriorate is important because drugs are most likely to work if given when people first start to experience mental impairment.
"Previous research suggests that our health in mid-life affects our risk of dementia as we age, and these findings give us all an extra reason to stick to our New Year's resolutions,” Dr. Simon Ridley, head of research at Alzheimer's Research UK, told BBC News.
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