Vitamin B12 deficiency can be caused by poor diet or malabsorption, leading to fatigue, muscle weakness, and memory problems.

Find Out The Health Benefits of Vitamins A, B, C and D March 18, 2011 — -- There are so many vitamins out there and they all do something different. "Good Morning America" is here to eliminate ...

Take vitamin B12 on an empty stomach in the morning or early afternoon to maximize absorption and avoid sleep disruptions. Vegans, older adults, and those with certain health conditions affecting ...

Oftentimes, vitamin C (for your immune system) and vitamin B (for nerve health and energy) get the attention. But a dietitian ...

Vitamin K2 has a slew of health benefits, including supporting bone and heart health. Here, dietitians share what it does and ...