7) Use vitamins & supplements wisely!

I am not big on vitamins and other nutritional supplements. Several large-scale studies have failed to show any benefit of taking nutritional supplements, or have even shown some adverse effects . More importantly, you can get all nutrients from healthy food. So, I don't see why you should spend your money on such supplements. Big companies sometimes imply in their advertisements like that vitamins are natural, and hence safe to take. However, high amounts of some vitamins can be dangerous. For example, high doses of vitamin D can lead to kidney conditions and excessive amounts of vitamin A can cause liver damage. 

Having said this, nutritional supplements are absolutely necessary if you suffer from vitamin or iron deficiency. I advise to check this out with your local doctor. Your doctor can request a blood test for vitamins, iron, and electrolytes. There is some evidence that vitamin D deficiency is related to depression and poor cognitive function . You might consider taking vitamin D supplements if you are not regularly exposed to natural light. Low iron can lead to low blood (anaemia) which shows itself with fatigue and low mood.    

Seafood is generally considered as healthy. It is often recommended to have seafood (such as salmon, trout, and tuna) at least twice a week . Some research studies have found evidence about the benefit of fish oil in brain development and mental illnesses . Fish oil contains Omega 3 fatty acids that are widely available as an over-the-counter supplement. Although there were some promising findings early on, there is now a controversy about whether fish oil supplements can prevent depression and anxiety