In research conducted for the pressure group by De Montfort University, over-55s were expected to account for the majority of votes cast in 94 marginal constituencies.
The findings also suggest that feeling great occurs more often later in life, with 21 per cent of over 55s saying they have a feel great moment every day.
Various studies show health benefits when participants eat an apple between three and five times a week, but all ailments cannot be cured by diet alone.
Those who began smoking within a month of the study's start were four times as likely to be depressed at the study's end than those who did not begin smoking.
In 2003 a large Finnish study found that sons of women who were depressed during pregnancy had an increased likelihood of being arrested for criminal ACTS before they turned 30.
A study in 2013, for example, found that nearly 17 percent of unemployed Americans were depressed, compared to almost six percent of those who had a permanent job.
Previous studies have generally focused on people who were depressed or anxious, Miller said. Or they looked at both depression and anxiety, but lumped all types of anxiety together.
That study looked at nearly 28,000 Norwegian mothers and found that those moms who were more anxious, depressed and angry were more likely to feed their kids unhealthy diets.