21st Century Stress B Multivitamin Tablets With Zinc For Energy & Immune Support Is a multivitamin formula designed to replace key nutrients that support the immune system and help manage the effects of stress, as during periods of unusual physical stress the body uses more vitamins than normal and taking this supplement may benefit those who do not get enough B vitamins from other sources, while B vitamins play a vital role in releasing energy from carbohydrates, fats, and proteins, help maintain a healthy nervous system, act as cofactors in the synthesis and regulation of dopaminergic and serotonergic neurotransmitters involved in mood regulation, support immune system function through cell health, red blood cells, energy levels, and cardiovascular health, and Zinc plays an essential role in immune cell development and function and supports the stress response by helping stabilize serum cortisol levels over time.