Health professionals will be able to calculate a patient's "brain age" based on their weight, exercise habits, cholesterol levels and alcohol intake to see if their lifestyle is affecting their risk of developing diseases such as Alzheimer's and dementia.
Dr Charles Alessi, Public Health England's lead on dementia, said the "personalised tool" would help middle-aged patients to understand how their lifestyle impacts on their health.
He said: "We are talking about giving people an opportunity early in their lives to be aware of the risk factors that could impair their health later in life.
"This is a personalised way of enabling people to see how those risk factors, like smoking and drinking, are affecting them and gives them the ability to take immediate action if they need to.
"We are not compelling people to do anything but we know people are very sensitive to dementia and interested to see if they can manage their risk and lifestyle better. If people manage their risk factors better they can delay a whole host of issues including dementia, diabetes and heart disease."
He added that the computer-based checks are in the early stages of development but could be carried out by GPs or pharmacists.
If successful they could become part of a system of checks already offered to people between the age of 40 and 74.
The number of people with dementia is expected to double by 2040 to more than than 1.5 million, according to the Department of Health.
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Hilary Evans from Alzheimer's Research UK said: "We need to encourage people to consider their brain health in the same way they think about their heart health.
"Increasing evidence suggests we can protect against cognitive decline and possibly dementia by adopting a range of healthy lifestyles and dietary habits, much of our risk might be within our own power to control.
"Tools to help analyse brain health must be backed up by the best evidence and should be sensitively employed, but if they can spur positive action to improve cognitive health this would be hugely valuable."