This is an interesting question, as the answer depends somewhat on what you consider to be the main purpose of meditation. For some people, they meditate purely to feel calmer; therefore, feeling calm isn’t a fringe benefit, rather the whole reason they meditate in the first place.
However, if we take the yogic idea that we meditate in order to better understand the nature of our mind, then this leaves a whole host of fringe benefits to be explored and enjoyed. All of the following have been found by scientists and researchers to be benefits of a regular meditation practice:
Boosts Physical Health
There are a few mechanisms by which scientists believe meditation can have a direct impact on your health on a measurable, physical level. It decreases cellular inflammation, helps reduce your perception of pain intensity and unpleasantness, and boosts your immune system.
In studies of mental health, meditation has been found to be effective in reducing stress, anxiety and depression. In addition, practicing a loving-kindness meditation, or metta bhavana, has been found to increase the experience of positive emotions in day-to-day lives, possibly because it trains the brain to think and feel more positively. (What's keeping us from happiness?)
Improves Emotional Control
Do you find yourself shouting at other drivers who cut you off? Or find your day ruined by a negative comment from someone? If so, meditation could help. It’s been found to increase your mindful regulation of emotions, helping you to stay happier. It also develops your capacity to be more introspective. (What can meditation tell me about myself?)
Perhaps unexpectedly for a practice that involves “doing nothing,” meditation can actually increase your productivity and performance. This is because it boosts memory, improves your ability to focus, and increases your concentration. It’s even thought to enhance your ability to multitask.
Enhances Social Well-being
Meditation has also been found to decrease feelings of loneliness, and increase feelings of social contentedness. It helps you to be more compassionate and even to develop greater emotional intelligence, something your friends will surely thank you for!
So, even if you’re not sure you want to meditate to better understand your mind, connect to your inner self or seek enlightenment, it’s worth giving it a go for the fringe benefits alone. (How do I begin meditating?)