Cobalt is an essential trace element for all multicellular organisms, including humans. It is required for the synthesis of vitamin B12, which is essential for the function of red blood cells and the proper functioning of the nervous system. Cobalt is also involved in the production of other important molecules, such as methionine and cysteine, and it plays a role in energy production and metabolism.

Although cobalt is essential for life, it is important to note that too much cobalt can be toxic. Cobalt toxicity can cause a variety of health problems, including heart disease, kidney damage, and respiratory problems. The recommended daily intake of cobalt is 1 microgram per day.

Cobalt is found in a variety of foods, including meat, fish, poultry, dairy products, and nuts. It is also present in some plant-based foods, such as legumes, whole grains, and leafy green vegetables.