A new study has suggested that low IQ and a lack of exercise in the teenage years could increase the risk of dementia.
Researchers in Sweden undertook a large survey that analysed over 1.1 million young men to determine the likelihood of developing the condition before the age of 60.
They concluded that the boys who had poor cardiovascular fitness levels were 2.5 times more likely to develop dementia at some point during their life.
Those with a low IQ were four times more likely to suffer from the disease, while those who fell into both categories increased their odds by seven times.
Georg Kuhn, lead author of the report, said: "Exercising can be used both as a prophylactic and a treatment for those in the risk zone for early-onset dementia."
He added that the increased risks remained the same regardless of other factors, such as heredity, socio-economic situations and medical history.
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