The Law of Diminishing Marginal Utility (DMU) in Economics has deep philosophical implications and if applied wisely, has the potential to bring drastic and positive changes to your life. The original idea existed long before classical economics formalized as a body of knowledge, of course. The ancient Sanskrit phrase, अति सर्वत्र वर्जयेत् (Ati sarvatra varjayet or anything in excess is bad) is a very simplistic expression of this exact same truth.
In fact, there isn't anything difficult to theorize or learn about this concept, understanding DMU is just so simple. As you keep consuming more and more of any one product or commodity, its utility or usefulness of subsequent helpings keeps on decreasing.
Though this is a very common sense thingy, its still important to be constantly aware of this truth because our mind has a tendency to keep falling into repetitive patterns. For some reason, our mind and the nature itself is anti-DMU at its core, it wants to keep repeating existing patterns, be it in thoughts or atoms.
Take the example of OCD (Obsessive Compulsive Disorder), for instance. Its nothing but a condition where excessive thoughts keep pressurizing your mind to keep on doing the same acts again and again until people start calling you a lunatic. The same pattern of excesses can be seen in case of allergies and other conditions too such as depression and negative thinking.
In order to avoid this, you must bring variety in your life and always strive to avoid repetitive patterns by making a conscious effort. Even small life changes which might appear too simplistic can have the potential to remove mental stress and bring about happiness.
1. Frequency of consuming milk, tea, snacks, etc. Too much of anything is bad, and one of the commonest sign of depression is a person eating same kind of food again and again unconsciously as if on an autopilot. Don't do that, especially with junk food. If you cannot switch to absolute fat-free or zero-cholestrol then at least try to bring a variation in the junk you consume.
2. Alternate talc, toothpaste, etc. Just as insects and cockroaches gain immunity if you keep using the same kind of pesticides against them, so do the bacteria in your teeth and body. Changing your toothpaste is one of the most pleasant experience, it breaks a pattern. If you are using Colgate now, use Vicco or Pepsodent next month, keep alternating. Same with talc, deo, perfumes, etc.
3. Alternate forms of infotainment. Books are the best friends of humans but if you keep reading the same kind of books, its unhealthy and unwholesome. Don't just read novels, read non-fiction for a change or even technical books. Visiting blogs and wikipedia once in a while is also quite refreshing.
4. Alternate forms of entertainment. Same with entertainment, watch Youtube for a while, then watch TV. Watch movies for a while and listen to a bit of music. Same holds true about consuming only one kind of news too, your mind becomes toxic and heavy with just one kind of ideology. Instead, keep consuming multiple forms of news through multiple mediums. Eventually, you might prefer some more than others and that's fine but there should be at least some variety or variation.
5. Keep meeting new people, switch jobs and projects. Many people already do it but many are also afraid of leaving the comfort of existing job position and trying out new ventures. If you don't meet new people and explore new opportunities, how will you know your true potential? Not only that, you also tend to stagnate and become quite depressive if you keep working in the same environment for a very long time.
6. Themes and Dark Modes. Believe it or not, but I've found that changing the looks or interface of an application or browser provides a great refreshment to your mind! Dark Mode is liked by many but there is a reason that most apps provide a toggle switch for it - they do like to switch it often.