High levels of homocysteine, poor antioxidant status and increased oxidative stress have been associated with the risk of chronic kidney disease. Deficiencies of vitamin B6, folic acid and vitamin B12 can lead to high homocysteine levels. A study, published in Nutrition (2016 Feb;32(2):236-41. doi: 10.1016/j.nut.2015.08.016. Epub 2015 Sep 25) looked at Ninety-seven patients with chronic kidney disease and 135 healthy subjects. They found that high homocysteine, low B6, increased oxidative stress, and decreased antioxidant enzyme activity (superoxide dismutase activity) were independent contributing factors in the development of early stage chronic kidney disease.