DEPRESSION

SELENIUM
(1 microgram = 0.001 milligrams)

1. Compared to placebo, daily supplementation with selenium (100 micrograms for 5 weeks) elevated mood and decreased anxiety. Low levels of selenium were associated with increased anxiety, depression and tiredness; symptoms which were improved after 5 weeks of selenium supplementation.

Biol Psychiatry. 1991 Jun 1;29(11):1092-8. 
The impact of selenium supplementation on mood.
Benton D, Cook R.
PMID: 1873372

VITAMIN B3/NIACIN
(1 gram = 1000 milligrams)

2. A combination of tryptophan (4 grams/day) and nicotinamide (1.0 grams/day) was as effective as the antidepressant imipramine in unipolar depressed patients.

Acta Psychiatr Scand. 1979 Apr;59(4):395-414. 
Tryptophan-nicotinamide, imipramine and their combination in depression. A controlled study.
Chouinard G, Young SN, Annable L, Sourkes TL.
PMID: 155389

ZINC
Animal Study

3. A dose of zinc (65 mg per kilogram body weight) had antidepressant effects in rats.

Brain Res Bull. 2003 Jul 15;61(2):159-64. 
Antidepressant-like effects of acute and chronic treatment with zinc in forced swim test and olfactory bulbectomy model in rats.
Nowak G, Szewczyk B, Wieronska JM, Branski P, Palucha A, Pilc A, Sadlik K, Piekoszewski W.
PMID: 12832002