Back to the Index. Forms Vitamin B-1 is most commonly available in supplement form as thiamine hydrochloride. Back to the Index. Very good sources of vitamin B-1 include nutritional yeast, wheat germ, sunflower seeds, brown rice, soybeans and peanuts. Good sources include whole grains and nuts.
Thiamine is inactivated by alcohol, sulfites and the tannins found in coffee and tea.
Back to the Index. 1.6 mg Back to the Index. Thiamine deficiency Back to the Index. Side effects Nausea with large doses Sweating, sensation of warmth Back to the Index. Contraindications Hypersensitivity to thiamine products Back to the Index.