silver - the way we "feel", your mood, is nothing more than the result of the balance of neurochemicals floating around in your system at any given point.
sometimes the imbalance is caused by the stress of outside life events depleting those chemicals, sometimes its just an endogenous condition. In your case maybe the former.
whatever the cause, you can help your body/mind fix itself by providing it with the raw materials neccessary to kickstart things or manufacture neurochemicals. I've always found these to help alliviate feelings of "depression" or mental exhaustion in myself and family/friends:
1) l-tyrosine - increases norepinephrine synthesis, thus increasing alertness, normalizing sleep, etc. think of it as a healthy version of caffiene without the side effects or jitters. it also stimulates production of thyroid hormones to boost metabolism.
2) l-phenylanine - same as above, but quicker and harsher .
3) l-glutamine - reduces cortisol levels and helps lifts the "brain fog" that often comes with depression (helps clear ammonia, and competes with tryptophan to cross blood-brain barrier- excess tryptophan leads to that "brain fog" feeling))
4) whey protein- a natural way to increase serotonin levels. studies have shown diets hi in whey increase serotonin levels ~50% more than diets that dont. as you probably know, serotonin is the "happy/coping chemical" in your brain. many of the anti-depressant drugs like prozac work by increasing or preserving S levels. While the anti-depressant drugs may have been overkill for you, a gentle nudge using this natural therapy may be more to your liking
5) send Mava noods - may or may not do anything for you, but they'll make _me_ happy
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