Ten supplements, rated by how strong the evidence really is

The marine fats your brain is partly built from. When mood runs low, an EPA-rich omega-3 is among the better-studied nutrients worth raising with your doctor — a supportive nutrient alongside diet and care, never a treatment on its own.

The 'sunshine vitamin' doubles as a hormone precursor involved in brain function. Low vitamin D status is consistently linked with low mood — especially in winter and indoor lifestyles.

A gentle, highly absorbable form of magnesium — the mineral your nervous system uses to downshift. A favorite for evening wind-down, stress resilience and sleep quality.

The quiet co-factors your brain leans on to build its own neurotransmitters. When B12 or folate run low, fatigue and flat mood often follow — which is why they're worth getting right before reaching further.

The adaptogen people reach for when stress feels relentless. It's the most studied root for everyday tension — standardized extracts like KSM-66 have, in several trials, eased perceived stress and cortisol against placebo.

The amino acid that makes green tea calming rather than jittery. L-theanine promotes a state of relaxed alertness without sedation — useful for stress and focus alike.

The world's most expensive spice is also a surprisingly well-studied mood-support botanical, with several trials using standardized extracts showing meaningful effects.

An adaptogen from cold northern climates, traditionally used for fatigue and burnout. Best known for supporting mental stamina when you're running on empty.

A direct serotonin precursor derived from the Griffonia seed. Potentially the most potent mood-related supplement here — and for exactly that reason, the one that demands the most caution.

The gut and brain are in constant conversation along the vagus nerve. Specific 'psychobiotic' strains are an exciting — if still early — frontier in mood and stress research.