A new study published in last month’s American Journal of Epidemiology suggests that the cognitive decline that often accompanies advancing age may have to do, in part, with how many unhealthy habits one has picked up along the way. The research adds to a growing body of evidence underlining the strong connection between bodily health and brain health.

Severine Sabia and her team at the Hopital Paul Brousse in Villejuif, France, surveyed over 5,000 participants at three points during a 17−year period – the participants were 44, 56, and 61 years old at each follow−up. The researchers looked at the effect that smoking, not exercising, not eating enough fruits and veggies, and interestingly, not drinking any alcohol had on the participants’ risk for cognitive problems as they aged.

People who abstained from alcohol entirely also had decreased cognitive abilities compared to those who consumed between one and 14 drinks per week.

After controlling for factors like socioeconomic status and gender, the team found that the individuals with the most bad health habits were three times more likely to have deficits in thinking skills and two times more likely to have memory problems than people who had no unhealthy habits.

Which habit was hardest on the aging brain? Sabia and colleagues found that smokers were the most likely to have memory problems as well as deficits in thinking and reasoning skills – both math and verbal – at each follow−up period. People who abstained from alcohol entirely also had decreased cognitive abilities compared to those who consumed between one and 14 drinks per week, adding evidence to the notion that a little wine is not only good for the heart, but good for the brain as well. The authors urge people to think about – and, if necessary, change – lifestyle habits early on, in order to protect against cognitive problems that may develop later in life.

A related study in the journal Neurology also reports that people over 45 who have high diastolic blood pressure also have more cognitive impairment than those with normal blood pressure. (Diastolic blood pressure is the bottom number in a reading, and represents the pressure that exists when the heart is at rest, between beats.) In fact, for every 10 points that diastolic blood pressure increased, the risk for cognitive deficits rose by 7%. The researchers suggest that this relationship probably exists because high blood pressure is hard on the arteries, and weakens even small vessels in the brain, which can lead to damage to certain areas in the brain over time. This study, like the first, points to the strong connection between overall health and mental health – something to keep in mind as we make our lifestyle choices every day.