Exercise regularly (especially at a moderate-to-high intensity) and eating a healthy diet rich in fruits and vegetables have been shown in numerous studies to improve your mood by decreasing inflammation and altering other physiological changes.

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However, according to the Journal of Happiness Studies researchers, these aren't the only reasons certain lifestyle choices make individuals happy. According to the study's findings, the pleasure that has been postponed may also have an effect.
In the United Kingdom, researchers looked at data on various characteristics, including physical activity and fruit and vegetable consumption, to determine whether or not their lives were happier than average. Overall enjoyment was associated with both of these factors, which the researchers believe is due to the capacity to recognize the long-term advantages of excellent practices. Higher concentrations of both were discovered.

To put it another way, choosing a healthier lifestyle now in the hopes of enjoying the advantages later was found to be the most significant predictor of happiness in later life.

According to the study's lead author, Adelina Gschwandtner, Ph.D., senior lecturer in economics at the University of Kent, a healthy lifestyle, defined here as eating fruits and vegetables and [getting] exercise, is beneficial not only to one's health but also to one's happiness. "A healthy lifestyle, defined here as eating fruits and vegetables and [getting] exercise," she says.

She claimed that this isn't obvious since, according to common knowledge, happy people eat better and exercise more than unhappy ones. However, a deeper examination of the material they obtained reveals something very different.
As she expressed it, we've demonstrated that one's manner of life impacts happiness in the opposite direction of what one might predict. Thus, eating fruits and vegetables and indulging in physical exercise will enhance your level of pleasure due to their nutritional value. Consequently, making an effort to live a healthy lifestyle pays off in the long term since you will be happy as a result. As well as weight training on two days per week, 150 minutes of moderate-intensity aerobic activity per week or 75 minutes of vigorous-intensity aerobic activity per week is advised. The importance of this cannot be overstated.
She clarified that this is not the same as immediate gratification. Suppose you resolve in January to eat more fruits and vegetables or to exercise more regularly. In that case, you are going against the feeling of delayed gratification since you are essentially seeking a rapid remedy.

According to Gschwandtner, New Year's resolutions frequently fail because they lack the long-term emotional commitment required to promote activity and enjoyment.

The solution to this problem is as follows: Do not make changes that will benefit you for decades in the future if you are not pleased with the current situation. Decide now to take action rather than waiting for advantages to become available down the road—which may be years away. You could find that doing so gives you an unexpected psychological boost.