B12 supplements are known to play a crucial role in maintaining healthy nerve cells, which are essential for cognitive function. Studies have shown that B12 supplements may improve memory and concentration, especially in older adults. In addition, B12 supplements may reduce the risk of developing dementia and Alzheimer's disease, two conditions that are associated with cognitive decline. For example, a study conducted by the University of Oxford found that individuals with higher B12 levels had better cognitive function and a lower risk of developing Alzheimer's disease. Another study published in the Journal of the American Geriatrics Society found that B12 supplements improved memory and cognitive function in older adults with mild cognitive impairment. B12 supplements are also known to help convert food into energy, which is essential for maintaining optimal energy levels. B12 supplements may reduce fatigue and improve endurance, making them popular among athletes and individuals with busy lifestyles. For example, a study published in the Journal of Alternative and Complementary Medicine found that B12 supplements improved endurance and reduced fatigue in athletes. Another study conducted by the University of California found that B12 supplements improved energy levels and reduced fatigue in individuals with chronic fatigue syndrome. In addition to cognitive function and energy levels, B12 supplements have been associated with a range of other health benefits. B12 supplements may improve heart health by reducing homocysteine levels, a compound that is associated with an increased risk of heart disease. B12 supplements may also improve mood and reduce symptoms of depression, as well as improve skin and hair health by promoting cell growth and repair. For example, a study published in the American Journal of Clinical Nutrition found that B12 supplements reduced homocysteine levels and improved heart health in older adults. Another study published in the Journal of Psychopharmacology found that B12 supplements improved mood and reduced symptoms of depression in individuals with depression.