Can These 4 Supplements Help You Manage Chronic Kidney Disease (CKD)?
CKD can cause certain nutrient deficiencies, but you need to be cautious with supplements.
Note: The U.S. Food and Drug Administration (FDA) does not approve supplements for safety or effectiveness. Talk to a healthcare professional about whether a supplement is the right fit for your individual health, and about any potential drug interactions or safety concerns.
If you have chronic kidney disease (CKD), you may have an enhanced need of vitamin and mineral supplements, but your condition can also make taking dietary supplements risky.
“When it comes to supplementing in the kidney disease population, I get nervous,” says Chicago-based Melanie Betz, RD, who specializes in kidney health and nutrition.
Betz says that it is the job of the kidneys to filter and remove extra waste from your body, including excessive vitamin amounts, so people with CKD are especially vulnerable to vitamin toxicity.
“Your body has a limited capacity to get rid of waste, which is why I urge patients to be careful with supplementing,” she says.
Some people will be advised to take supplements to address the nutritional deficiencies that are common in people with CKD, a result of dietary restrictions, medication interactions, and impaired digestion and nutrient absorption. But people with CKD should only use the specific supplements advised by their doctors, and are not generally advised to take multivitamins or other dietary supplements.
Always talk to your healthcare provider, such as your kidney doctor or a registered dietitian, before taking any of the following popular supplements for CKD.
1. Vitamin D
As many as 85 percent of people with later-stage CKD may have insufficient vitamin D levels. The kidneys help convert vitamin D into its active form, allowing it to help absorb calcium and promote bone health. When kidney function declines, the body can struggle to get as much vitamin D as it needs.
This is why people who have CKD are at risk for CKD–mineral and bone disorder, which lowers bone quality and causes hardening of blood vessels that contributes to heart disease.
If you have vitamin D deficiency, your healthcare provider may recommend the use of a supplement or prescribe prescription-strength vitamin D medicine. However, there is relatively little evidence that taking vitamin D supplements significantly improves the long-term health of people with CKD.
Bets says that you should only take vitamin D and similar supplements for your CKD under the advice and supervision of your healthcare provider, who also can advise on dosage and type of vitamin D.
2. Calcium
Lack of vitamin D plus excess phosphorus in your blood when you have CKD can make it harder for you to absorb calcium. This can lower your serum calcium, or the calcium in your blood, which can increase your risk of kidney failure.
Many people get enough calcium from a balanced diet. This can be more challenging for people with CKD, however, especially if they’ve been advised to limit or cut out dairy and other foods that are high in calcium as well as phosphorus.
You should only take calcium supplements on the advice of your healthcare provider, who can monitor the correct amount for your needs. Calcium supplements must be carefully balanced, and people with CKD also run a risk of excessive calcium. Too much calcium can cause calcium deposits in your heart, lungs, and blood that may lead to complications.
3. Iron
CKD can make it harder for your body to absorb iron from the food you eat. You may also be advised to limit foods that are naturally high in iron, such as eggs and red meat.
If you’re short on iron, your body may not be able to make enough new red blood cells. As a result, you can develop anemia when you have CKD, Betz says.
Oral iron supplements (either liquid or pulls) are good options to address anemia. Because the risk of iron deficiency and anemia grows as you enter later-stages of CKD, your doctor may eventually prescribe intravenous (IV) iron supplements.
Like all of the supplements on this list, it’s important not to take iron supplements without your doctor’s okay and advice about what form and dosage is right for you.
The medications, supplements, or foods you consume can significantly affect your body’s ability to absorb iron. High fiber ingredients, calcium supplements, and antacids, for example, can all block iron absorption. Iron supplements can also lead to side effects such as gastrointestinal distress and black stools. To ensure that your supplement is effective, you may need to discuss the details of how and when you take it with your healthcare provider.
4. Probiotics
Probiotics are live microorganisms, such as bacteria and yeast, that can be consumed to help improve the health of your digestive system. Taking or consuming probiotics through fermented foods, as well as via supplements, may balance your gut microbiome. Benefits may include helping your digestive system absorb nutrients and reducing inflammation.
Little research exists, however, about the exact role probiotics might play, especially in CKD. One meta-analysis says that probiotics can contribute to improved kidney function and limit kidney damage. Others note that larger studies are needed to show probiotics’ potential long-term impact.
“The science is not quite there yet,” Betz says. “We know that gut bacteria have a role to play, but it’s not quite clear on what type of probiotics will make a difference.”
Vitamins to Avoid: Vitamins A, E, and K
Vitamins A, E, and K are fat-soluble vitamins that are specifically risky for people with CKD.
“Fat soluble vitamins can accumulate in the body because they are stored in fat, causing a greater potential for toxicity," Betz says.
Loss of kidney function reduces your body’s ability to remove these vitamins when there is too much in the body, which means that people with CKD can easily amass unhealthy levels.
The early side effects of having too much of vitamins A, E, and K in your body include nausea and dizziness, but toxicity can eventually lead to organ failure and even death. Although some research promotes the benefits of these vitamins for people with CKD, taking them routinely as supplements generally is not recommended.
Keep in mind that these vitamins tend to be present in multivitamins, as are other minerals that people with CKD are sometimes asked to avoid, such as potassium. Betz typically doesn’t recommend using a multivitamin at any stage of CKD.
“If you’re eating a healthy diet, I don’t feel that there’s a need for a general multivitamin,” she says.
The Takeaway
People with chronic kidney disease (CKD) may have nutrient deficiencies due to low intake from dietary restrictions, medication interactions, and effects of related conditions.
Although supplements such as vitamin D, calcium, and iron may have benefits, you should only use them on your doctor’s recommendation.
Vitamins A, E, and K, which can be found in many multivitamins, may be harmful for people with CKD; do not take supplements containing these vitamins unless specifically asked to by your doctor.
People with kidney disease need to be very careful about using vitamin and mineral supplements. Contact your doctor for individualized recommendations tailored to your specific health situation.
