Much unfolding research points to the importance of vitamin D for everything from bone health to prevention of diabetes, cancer, depression, obesity, and heart disease. The CDC’s latest information, though, finds that more than half of Americans have low levels of the vitamin, and kidney patients are more likely to suffer from a deficiency.
Why is vitamin D connected to the kidney? The kidneys are important in helping the body use vitamin D. Vitamin D comes from two sources–either exposure to the sun’s ultraviolet B radiation or absorption from food or supplements. The kidneys then must convert this vitamin D to the active form of vitamin D usable by the body. With chronic kidney disease (CKD), low vitamin D levels result because damaged kidneys are less able to convert vitamin D into its active form.
In a study published in the Journal of Clinical Endocrinology and Metabolism, Researchers analyzed data from nearly 247,600 people, looking at the connection between vitamin D and death. Over a seven-year period, 16,645 patients had died. Those with low vitamin D levels — around 12.5 nmol/L — had over double the risk of heart disease compared with those who had vitamin D levels of 70 nmol/L.
Surprisingly, those at very high levels — about 125 nmol/L — also faced increased cardiovascular mortality risk. The findings suggested a correlation between mortality rates and too low levels of vitamin D, or too high levels.
Studies like this are important in CKD because kidney patients suffer much higher than normal rates of cardiovascular disease. In fact, most kidney patients die prematurely from the cardiovascular disease rather than their CKD, reports the USRDS.
Ask your doctor to check your vitamin D level with a simple blood test. Levels below 50 or over 100 nanomol per liter may suggest a greater likelihood of stroke or heart attack. Levels should be somewhere in between 50 and 100 nanomol per liter. Perhaps, 70 is preferable.
Talk with your doctor before taking supplements. You could overdo it, and there are different types of vitamin D. Kidney patients often require a special form.
Order our “Smoothies for Kidney Health” for more on foods and slowing CKD progression.