It’s easy to think that grabbing any daily multivitamin at the store would better your health. However, in the case that you have CKD, this isn’t all that true. Everyone with kidney problems has different needs for various vitamins and minerals, but how do you know what vitamins for kidneys to get?
There are varying dosages, different names for the same vitamins, store brands vs name brands, and the list goes on.
Don’t stress! This is the second to a multi-series guide (Click here for the Part One!) that lays out all the essential vitamins and minerals. This articles gives special attention to the best vitamins for kidneys.
This article was written by dietetic student Alexia Davila and reviewed by Jen Hernandez RDN, CSR, LDN.
This article contains affiliate links in which I earn a small percentage of sales, at no expense to you. As an Amazon Associate, I earn from qualifying purchases. This supports my website and ability to write up more helpful content – thank you for your support!
Please note: the dosage recommendations in this post are based on the Dietary Reference Intakes (DRIs), which include Adequate Intake (AI), Recommended Daily Allowance (RDA), and Estimated Average Requirements (EAR) that are developed by the Institute of Medicine and serve as a base guideline for vitamins and minerals in this article. Recommendations are not meant to be taken as medical advice. Talk with your medical provider about what dosages are right for you.
Table of Contents
What are vitamins?
Vitamins (and minerals) are essential organic substances needed in small amounts in a diet. Unlike protein, fats, and carbohydrates, vitamins are not a source of energy, meaning they do not contain calories.
Rather, they aid in energy metabolism. In other words, they help you get the energy you want out of your food by playing a part in the chemical reactions that take place in your body when digesting food.
There are two main categories of vitamins: water-soluble and fat-soluble. Water-soluble vitamins can be delivered directly to the bloodstream to be distributed throughout the body.
Fat-soluble vitamins, on the other hand, require help from the liver to “repackage” them and make them safe to float through the bloodstream, or they will be stored in our fat tissue for future use.
How do I know if I need to take any?
Those with chronic kidney disease (CKD) may need higher amounts of certain vitamins and minerals, especially for patients who are on dialysis. However, your nephrologist or RD should let you know if you should be taking supplements. Your doctor can order a micronutrient lab panel to test your values.
Another option is to take a micronutrient deficiency test, such as Spectracell, which tests for 31 vitamins, minerals, amino and fatty acids, antioxidants, and metabolites. However, this test may require a physician order. You can then bring your results to your medical provider and they can give you more guidance on which supplements would be best for you.
Should I take herbal remedies?
In general, avoiding herbal remedies is your safest bet. Consult with your doctor or RD if you are curious about taking any herbal remedies. Often times, they can have unknown and/or adverse effects on other medications you are taking.
Vitamins and Chronic Kidney Disease
There is no single “best” vitamin for patients with CKD. However, there are some that are more commonly deficient than others. People with CKD often have a higher need of water-soluble vitamins and should be wary of taking excess amounts of fat-soluble vitamins, as overconsumption can cause toxicity in the body.
Water Soluble Vitamins for Kidneys
Vitamin B₁ – Thiamin
The name for vitamin B₁ is often used interchangeably with thiamin, or thiamine. This doubling of names goes for many of the other B vitamins.
Function
Thiamin’s primary function is in helping your body get the energy it needs out of the food you eat. This is especially important for children who are still growing and developing. It also plays a role in muscle contraction and sending nerve signals.
Many studies have explored the connection that thiamin levels have in relation to cognitive function. Evidence has shown that blood thiamin levels were much lower in patients with dementia and delirium than those without.
Forms of Thiamin
The main form of thiamin in the body is also known as thiamin diphosphate, or, TDP. This is the form that helps your body get the energy it needs from the food you eat.
The other form in the body is produced by the bacteria in your gut. Similar to vitamin K, it is unknown how much of this form we actually benefit from.
To note, Thiamin is sensitive to heat and can be easily lost or destroyed. For this reason, you will most likely find thiamin as thiamin mononitrate or thiamin hydrochloride in supplements. These forms of thiamin are both stable and water soluble.
Recommended Intake and Deficiency
The recommended daily intake of thiamin for adult males 14 years and older is 1.2mg and 1.0mg for women 14-18 years, increasing to 1.1mg after 19 years. However, individual needs may vary. Please consult with your doctor if you are interested in supplementing.
Moderate thiamin deficiency can cause unintended weight loss, anorexia, confusion, short-term memory loss, muscle weakness, and cardiovascular symptoms.
Severe thiamin deficiency, on the other hand, exhibits itself as beriberi. However, it is not very common in the US as many of our foods are fortified with many vitamins and minerals, including thiamin.
Side effects of beriberi include weakness and pain from nerve damage, impaired movement, and, on rare occasions, lead to congestive heart failure.
The most common presentation of thiamin deficiency in the US is Wernicke-Korsakoff syndrome. Those suffering from alcoholism are at the highest risk, though it is also seen in patients with gastrointestinal disorders, drug addiction, and AIDS. Wernicke-Korsakoffe syndrome encompass the same signs and symptoms as beriberi.
Tolerable Upper Level Intake
Excess thiamin in the body gets excreted in the urine, therefore over consumption is not a common health concern.
However, when kidney function is decreased, your body’s ability to get rid of extra water-soluble vitamins is affected. Evidence has shown that long-term diuretics use can lead to a thiamin deficiency, which can have harmful effects on the heart. Be sure to talk with your doctor about if and how much thiamin you should take.
Drug-Nutrient Interactions
There are no known medications that thiamin interacts with. However, diuretics can cause a decrease thiamin levels.
If you are taking diuretics long-term, you may be at higher risk for thiamin deficiency. Therefore, talk to your doctor about getting a low dose thiamin supplement for you.
Sources of Thiamin
Many processed grains, such as white bread and white rice, are fortified with a variety of vitamins and minerals, including thiamin. It is also naturally found in whole grains, though in smaller quantities.
Meat and fish, specifically pork, can also be a good source of thiamin. On the other hand, fruits and vegetables have very low, if any, thiamin content.
See Table 4 for more food sources of thiamin.
| Food | Milligrams (mg) per serving |
| Rice, white, long grain, enriched, parboiled, ½ cup | 1.4 |
| Breakfast cereals, fortified with 100% of the DV for thiamin, 1 serving | 1.2 |
| Pork chop, bone-in, broiled, 3oz | 0.4 |
| Macaroni, whole wheat, cooked, 1 cup | 0.2 |
| Rice, brown, long grain, not enriched, cooked, ½ cup | 0.1 |
| Beef steak, bottom round, trimmed of fat, braised, 3oz | 0.1 |
Why is thiamin important for kidney disease?
Thiamin levels are typically normal and are not of particular concern when it comes to CKD patients. However, in the case that you are taking diuretics, it may be in your best interest to talk with your doctor about supplementing with a low dose of thiamin.
When taking diuretics, your body increases the amount of thiamin, along with other B vitamins, you get rid of through your urine.
For this reason, thiamin may be one of the better vitamins for kidneys if you are on diuretics.
Vitamin B₂ – Riboflavin
Function
Riboflavin helps reactions take place in your body that you need to produce energy, breakdown fats, process drugs, and grow.
Forms of Riboflavin
A majority of dietary riboflavin is in the form of flavin adenine dinucelotide (FAD), or flavin mononucleotide (FMN). In other words, most riboflavin within us is usually accompanied with other protein molecules to help facilitate essential bodily functions.
Only 10% of riboflavin is in free form- not attached to other molecules.
Your gut bacteria also produces some riboflavin. It has been found that “gut riboflavin” is better absorbed in the body after eating a vegetable dense meal compared to meat.
Most supplements use the free form of riboflavin and usually provide 100% of the daily value for the general population.
Recommended Intake and Deficiency
The recommended daily intake for adult men 19 years and older is 1.1mg and 0.9mg for women. Most people in the US get their daily recommended amount of riboflavin from their diet without supplementation.
Riboflavin deficiency is very rare in the US. Those at highest risk include:
- People with thyroid hormone insufficiency
- Vegetarian athletes
- Vegans
- Pregnant and lactating women & their infants
- People with riboflavin transporter deficiency
Signs and symptoms of riboflavin deficiency include skin disorders, swollen/cracked lips, hair loss, reproductive problems, and edema of the mouth and throat. Talk with your doctor if you are experiencing any of these conditions or fall under those that are at high risk for deficiency.
Tolerable Upper Level Intake
Riboflavin has a limited absorption rate in the body and consuming excess amounts has never had any observable impact. There are currently no upper level intake guidelines for riboflavin.
Drug-Nutrient Interactions with Riboflavin
There are currently no known interactions that riboflavin has with medications.
Sources
The highest sources of riboflavin come from organ meats, such as liver and kidneys.
However, if the idea of consuming organs makes you wince, there are plenty of alternatives! The most common contributor of riboflavin in the average American diet is milk, fortified bread products, fortified breakfast cereals, and eggs.
Some green vegetables, like spinach, also contain small amounts of riboflavin.
See Table 5 for a comprehensive list of food sources of riboflavin.
Table 5 Food sources of riboflavin
| Food | Milligrams (mg) per serving |
| Beef liver, pan fried, 3 ounces | 2.9 |
| Breakfast cereals, fortified with 100% of the Daily Value for riboflavin, 1 serving | 1.3 |
| Oats, instant, fortified, cooked with water, 1 cup | 1.1 |
| Milk, 2% fat, 1 cup | 0.6 |
| Cheese, swiss, 3 ounces | 0.3 |
| Egg, whole, scrambled, 1 large | 0.2 |
| Spinach, raw, 1 cup | 0.1 |
Why is riboflavin important for kidney disease?
Since the best sources of riboflavin don’t typically align with the diet restrictions of many CKD patients, it can be a challenge to make sure you are getting an adequate amount.
You may benefit from taking a multivitamin that includes thiamin and other water-soluble vitamins in smaller doses than normal. The end of this article will give you tips and information on how to choose the best vitamins for kidneys. Remember to always consult with your doctor before starting a new supplement routine.
Most importantly, the loss of riboflavin, along with other water-soluble vitamins, are much greater for those on dialysis. One study has shown that decreased riboflavin levels could be due to abnormal absorption in a CKD setting.
There is also evidence that shows the amount of available riboflavin in the body are indicative of total homocysteine levels. High levels of homocysteine in the body are linked to an increased risk of heart disease.
Vitamin B₃ – Niacin
Function
Niacin helps over 400 reactions in the body to extract energy out of the food you eat. It also helps to build molecules in the body like cholesterol, and takes part in reducing oxidative stress in the body.
Forms of Niacin
Once niacin is absorbed in the body, it is converted into its active form called nicotinamide adenine dinucleotide, or NAD for short. This is the form that helps hundreds of reactions take place in your body to carry out necessary bodily functions.
You may also see the name inositol hexanicotinate as a source of niacin on supplement labels. However, it is important to know that this form has a much lower absorption rate compared to NAD.
There is also a niacin-like compound called nicotinamide riboside commonly sold as a supplement that is similar, but it is not marketed as a source of niacin.
Recommended Intake and Deficiency
The recommended daily intake for niacin for men 14 years and older is 16mg of niacin equivalents (NE) and 14mg NE for women. However, most people in the US exceed this recommendation through an average diet and deficiency is rare.
A severe deficiency of niacin presents itself as pellagra. Physical signs and symptoms of pellagra include inflamed, red skin, bright red tongue, vomiting, constipation, and/or diarrhea. On the other hand, neurological side effects include depression, headaches, fatigue, and progressive memory loss. It can also lead to anorexia and even death if left untreated.
Tolerable Upper Level Intake
No adverse effects of consuming excess niacin from food sources has been reported. However, there is risk in consuming too much niacin in the form of a supplement.
Intake of 30-50mg of nicotinic acid is often accompanied with flushing. Flushing is caused by widening of small blood vessels and causes skin to turn a red “flushed” color. Burning, itching, and tingling sensations are also common.
Severe flushing can turn into headaches, rashes, and even decreased blood pressure. However, consumers can reduce the effects of flushing by taking a supplement with food and slowly increasing the dosage over time.
On the other hand, taking prescription niacin in the amounts of 1,000mg to 3,000mg a day can cause more severe side effects. This amount of niacin is often used to treat patients with hyperlipidemia. Hypotension (low blood pressure), fatigue, glucose intolerance, nausea, heartburn, and imparied vision can all occur as a result of excess niacin.
Drug-Nutrient Interactions with Niacin
Listed below are some medications that may adversely affect niacin levels. Talk with your medical provider before changing or starting a new supplement routine, especially if you take any of the following:
- Isoniazid and pyrazinamide (RifaterⓇ) for treatment of tuberculosis
- Antidiabetes medications
Sources
Animal-based foods like poultry, beef, and fish contain the most absorbable form of niacin. Plant-based sources like nuts and legumes also contain niacin, but in a different form that is absorbed at a rate of about 30 percent. See the table below for a list of both animal and plant-based sources of niacin.
Foods high in an amino acid protein called tryptophan can also contribute to niacin needs since it can be reformed in the body as niacin. Turkey meat is an especially high source of tryptophan.
Table 6. Food sources of Niacin
| Food | Milligrams (mg) per serving |
| Beef liver, pan fried, 3 ounces | 14.9 |
| Chicken breast, meat only, grilled, 3 ounces | 10.3 |
| Turkey breast, meat only, roasted, 3 ounces | 10.0 |
| Rice, brown, cooked, 1 cup | 5.2 |
| Peanuts, dry roasted, 1 ounce | 4.2 |
| Bread, whole wheat, 1 slice | 1.4 |
| Lentils, boiled and drained, ½ cup | 1.0 |
Why is niacin important for kidney disease?
Elevated levels of phosphate in the blood, known as hyperphosphatemia, is considered a risk factor for CKD mineral-bone disorder. This condition occurs when blood calcium and phosphorus levels are out of balance.
Since controlling phosphate consumption in the diet can be a challenge for many CKD patients, research has looked to niacin as a way to lower phosphate levels.
Research suggests a strong relationship between niacin and chronic kidney disease. One study has shown that niacin can help lower phosphorus levels by 10% for people in stages 1-3 of CKD.
Additionally, reports of increased glomerular filtration rate (GFR) with supplementation gives hope to the use of niacin as a way to help CKD patients, but more long-term research is needed to establish any health claims for this as part of beneficial vitamins for kidneys.
Vitamin B₅ – Pantothenic Acid
Function
Pantothenic acid, also known as vitamin B₅, assists in the process of creating and breaking down fatty acids. Making these fatty acids is essential for humans and helps us create our own cholesterol, store energy, and more.
Forms of Pantothenic Acid
About 85% of pantothenic acid in food is in the form of CoA or phosphopantetheine. Your body then breaks it down and shifts around the molecules to create a usable form for itself to help carry out necessary bodily functions.
The good bacteria in your gut, known as the microbiome, also create pantothenic acid but not in significant amounts.
Some dietary supplements contain pantethine, which is a byproduct of pantothenic acid and is commonly marketed as a way to lower cholesterol.
Recommended Intake and Deficiency
The adequate intake for pantothenic acid for adult men and women 14 years and older is 5mg per day. Since pantothenic acid is found in such a wide range of foods, deficiency is uncommon, especially in the US.
Deficiency is mostly reserved to those who are experiencing overall severe malnutrition and is accompanied by other vitamin and mineral deficiencies. A deficiency presents itself with numbness and burning in extremities, headache, fatigue, and irritability.
Tolerable Upper Level Intake
There are currently no TUL guidelines for pantothenic acid and there are no reports of toxicity of the vitamin. Consuming more than 10g a day may result in diarrhea and GI distress, but this amount would only be achievable through very high dosing of supplements.
Drug-Nutrient Interactions with Pantothenic Acid
Pantothenic acid may alter the effects of the medications listed below. Consult with your doctor before beginning a new supplement routine.
- Tetracycline (antibiotics)
- Drugs to treat Alzheimer’s disease
Sources
Luckily, nearly all animal and plant-based foods have some pantothenic acid content. One of the highest sources of pantothenic acid is beef liver, as is the case with many other B vitamins.
Pantothenic acid is also fortified in some processed foods, such as breakfast cereals. It is often added to energy drinks as well, although this is not a recommended source as energy drinks are linked to adverse health effects.
Table 7. Food sources of pantothenic acid
| Food | Milligrams (mg) per serving |
| Beef liver, boiled, 3 ounces | 8.3 |
| Breakfast cereals, fortified with 100% of the Daily Value | 5 |
| Shiitake mushrooms, cooked, ½ cup pieces | 2.6 |
| Sunflower seeds, ¼ cup | 2.4 |
| Chicken breast, skinless, roasted, 3 ounces | 1.3 |
| Avocado, raw, ½ avocado | 1.0 |
| Chickpeas, canned, ½ cup | 0.4 |
Why is pantothenic acid important for kidney disease?
While there is limited research on the relationship between pantothenic acid and kidney disease, it is still worthwhile to look at the benefits supplementing can have on CKD patients also struggling with dyslipidemia, which greatly increases the risk for heart attack or stroke.
CKD is commonly linked with high triglyceride levels in the blood and lower levels of “good” cholesterol. If you are struggling with these conditions, research has shown supplementing with pantethine, a form of pantothenic acid regarded for helping lower “bad” cholesterol, may help.
With that being said, there is still specific research needed to be done for pantothenic acid’s use as part of renal vitamins and its direct effect on the kidneys.
Remember to always speak with your medical provider before starting a new supplement routine as individual needs vary and may have adverse effects on some medications.
Vitamin B₆ – Pyridoxine
Function
Pyridoxine is a multifaceted vitamin involved in over 100 reactions in the body, most of which involve helping break down proteins. It helps to create neurotransmitters which makes it very important during growth.
It’s also important in maintaining normal homocysteine levels. High homocysteine levels in the blood is associated with an increased risk of coronary artery disease, heart attack, and stroke.
Forms of Pyridoxine
Pyridoxine is often found in the form of pyridoxine hydrochloride in supplements, but some use pyridoxal 5’ phosphate (PLP), which is known as the active form of vitamin B₆. The amount of vitamin B₆ absorbed by the body is similar for both supplements and food sources.
Recommended Intake and Deficiency
The daily recommended intake of vitamin B₆ for men 14-50 years is 1.3mg/day and increases to 1.7mg/day for men 51 years and older.
The recommendation for women 14-18 years is 1.2mg/day increasing to 1.3mg/day for 19-50 years, and again to 1.5mg/day for 51 years and older.
Most people in the US meet their daily needs of vitamin B₆, but having CKD can put you at a higher risk for deficiency. Therefore, it may be one of the best vitamins for kidneys to look into making part of your routine, but remember to always consult with your doctor first.
When someone is deficient in vitamin B₆, it usually is because someone is deficient in other B vitamins as well. Signs and symptoms of a vitamin B₆ deficiency include microcytic anemia, abnormal brain frequencies, dermatitis, swelling of the tongue, depression, and weakened immune function.
People with kidney disease will often have one or more of these signs and symptoms of deficiency.
Tolerable Upper Level Intake
There are currently no known adverse effects that come from high consumption of vitamin B₆ from food sources. High intake through supplementation can cause lesions, photosensitivity, nausea, and heartburn.
The TUL for vitamin B₆ is 80mg for adults 14-18 years and 100mg for those 19 years and older. These limits do not apply for those using vitamin B₆ as part of a treatment, but it is important to consult your doctor before starting a new supplement routine.
Drug-Nutrient Interactions with Pyridoxine
There are some known medications that can affect vitamin B₆ levels and also alter the effectiveness of certain drugs such as:
- Cycloserine (antibiotic for treatment of tuberculosis)
- Antiepileptic medications (for seizures)
- Theophylline (for treatment of asthma and other lung diseases)
Sources
The best sources of pyridoxine is, like many other B vitamins, beef liver and other organ meats. However, most people in the US get their pyridoxine through fortified cereals, poultry, regular beef cuts, and starchy vegetables.
See Table 8 for a list of food sources containing pyridoxine.
Table 8. Food sources of pyridoxine
| Food | Milligrams (mg) per serving |
| Chickpeas, canned, 1 cup | 1.1 |
| Salmon, sockeye, cooked, 3 ounces | 0.6 |
| Chicken breast, roasted, 3 ounces | 0.5 |
| Breakfast cereals, fortified with 25% of the Daily Value for vitamin B₆ | 0.4 |
| Potatoes, boiled, 1 cup | 0.4 |
| Banana, 1 medium | 0.4 |
| Bulgur, cooked, 1 cup | 0.2 |
| Squash, winter, baked, ½ cup | 0.2 |
Why is pyridoxine important for kidney disease?
PLP, the active form of pyridoxine, is often used as a way to measure levels of pyridoxine in the body. Evidence has suggested that low PLP levels is a contributing factor to the development of early stage chronic kidney disease.
As mentioned earlier in the function of pyridoxine, high homocysteine levels are known to be linked with higher risk of cardiovascular diseases (CVD). However, in those with CKD, there has not been success in reducing the risk of CVD through supplementation of pyridoxine.
Regardless, vitamin B₆ is still an essential vitamin and since it is commonly deficient in those with chronic renal insufficiency, it may be beneficial to take a supplement with pyridoxine included. Always check with your doctor first before taking new supplements.
Vitamin B₇ – Biotin
Function
Biotin helps to process fats, carbohydrates, and proteins in the body. It is unique in the fact that it helps with gene regulation and expression, which has led to opening the door to researching its link with neurological disorders.
The commonly advertised beauty claims that biotin helps with hair and nail growth are based on limited studies that lack sufficient evidence.
Forms of Biotin
Once biotin is consumed, it is broken down in the body into biocytin and biotin-oligopeptides and are further processed by other enzymes to obtain the free biotin that can be absorbed.
Biotin is available in supplement form as free biotin.
Recommended Intake and Deficiency
The adequate intake of biotin for men and women 14-18 years is 25mcg/day and increases to 30mcg/day for those 19 years and older.
Biotin deficiency is rare in the US. However, signs and symptoms of biotin deficiency include hair thinning, scaly, red rash around the eyes, nose and mouth, seizures, skin infections, brittle nails, and lethargy.
Most people can meet their biotin needs by eating a normal, varied diet.
Tolerable Upper Level Intake
There is currently no evidence that high biotin consumption causes toxicity in humans. However, taking large amounts of biotin in supplement form has been noted to affect lab results in thyroid function tests, vitamin D level tests, and more.
Drug-Nutrient Interactions with Biotin
Some medications can have an adverse effect on biotin levels, like the one listed below. It is important to speak with your doctor before starting a new supplement routine to avoid any possible drug-nutrient interactions.
- Anticonvulsants (treatment for epilepsy)
Sources of Biotin
A variety of foods contain biotin, although organ meats, eggs, fish, and seeds & nuts are amongst the highest sources.
See Table 9 for a list of foods that contain biotin.
Table 9. Food sources of biotin
| Food | Micrograms (mcg) of biotin |
| Egg, whole, cooked | 10.0 |
| Salmon, pink, canned in water, 3 ounces | 5.0 |
| Sunflower seeds, roasted, ¼ cup | 2.6 |
| Sweet potato, cooked ½ cup | 2.4 |
| Almonds, roasted, ¼ cup | 1.5 |
| Broccoli, fresh, ½ cup | 0.4 |
| Oatmeal, 1 cup | 0.2 |
Why is Biotin Important for Kidney Disease?
Research on biotin mostly covers its effects on pregnancy and the role it plays in gene expression. While there are no current published studies analyzing the relationship between biotin and kidney disease, it is still an essential vitamin and is beneficial to overall health.
Vitamin B₉ – Folate
Function
Folate is essential in the creation of DNA, making it a key nutrient during stages of growth such as pregnancy and adolescence. It also helps to produce red and white blood cells.
Forms of Folate
The folate that is naturally occuring in food (dietary folate), is known as tetrahydrofolate. When food is fortified with folate, folic acid is used.
Dietary supplements use a variety of forms of folate, including folic acid and 5-methyl-THF, which is often suggested for people with the MTHFR gene mutation.
You may also find folate presented in dietary folate equivalents (DFE). These values depict how different forms of folate are absorbed in the body.
For example, folate from food sources has lower bioavailability than that of folic acid, and therefore you would need to consume more folate from food to get the same DFE as folic acid from fortified foods. The DFEs are listed below.
- 1mcg food folate = 1mcg DFE
- 0.6mcg folic acid from fortified foods or dietary supplements consumed with foods = 1mcg DFE
- 0.5mcg folic acid taken from dietary supplements on an empty stomach = 1mcg DFE
Recommended Intake and Deficiency
The recommended daily intake of folate for men and women 14 years and older is 400mcg DFE. This need is increased to 600mcg DFE per day for pregnant women.
Folate deficiency alone is uncommon, as it is normally accompanied by another B vitamin deficiency. The most well known sign of folate deficiency is megaloblastic anemia, meaning that one’s red blood cells are abnormally large in size. However, this type of anemia can also be caused by a deficiency in vitamin B₁₂, so treatment usually involves supplementation of both B₁₂ and folic acid to cover both bases.
Deficiency can also cause a sore tongue, changes in skin, hair, and nail color, GI symptoms, and elevated homocysteine levels in the blood.
Pregnant women with folate deficiency are at high risk of giving birth to infants with neural tube defect, a common cause of spina bifida in babies.
Tolerable Upper Level Intake
The UL for folate from supplements or fortified foods is 800mcg/day for men and women 14-18 years and 1,000mcg/day for men and women 19 years and older.
There is no UL set for the amount of folate someone should have per day from non-fortified food sources, such as vegetables and whole grains.
Drug-Nutrient Interactions with Folate
Folate supplements can change the way certain medications work in the body. Always check with your doctor before starting a new supplement routine as it may change the effectiveness of your medication.
Some of the known medications to be affected by folate supplementation are listed below.
- Methotrexate (treatment for cancer and autoimmune diseases)
- Antiepileptic medications (treatment of epilepsy)
- Sulfasalazine (treatment of ulcerative colitis)
Sources of Folate
Folate is easily found in various foods. The highest sources include dark green leafy vegetables and legumes.
See Table 10 for a list of food sources of folate.
Table 10. Food sources of folate
| Food | Micrograms (mcg) of Dietary Folate Equivalents (DFE) |
| Spinach, boiled, ½ cup | 131 |
| Black-eyed peas, boiled, ½ cup | 105 |
| Rice, fortified white, medium-grain, cooked, ½ cup | 90 |
| Asparagus, boiled, 4 spears | 89 |
| Brussels sprouts, frozen, boiled, ½ cup | 78 |
| Broccoli, chopped, frozen, cooked, ½ cup | 52 |
| Kidney beans, canned, ½ cup | 46 |
| Peanuts, dry roasted, 1 ounce | 27 |
Why is Folate Important for Kidney Disease?
There is some research that shows folic acid therapy as an effective treatment in reducing the risk of cardiovascular disease (CVD) in patients with kidney disease. Given that about 85% of kidney patients have high homocysteine levels, a risk factor for CVD, studies regarding the efficacy of folic acid as a treatment in lowering homocysteine levels give hope in lowering the incidence of CVD in those with kidney disease.
However, more research is needed to verify these claims. There are also contradicting studies that have concluded that supplementation does not reduce the risk of CVD, but rather only reduce the risk of stroke.
Vitamin B₁₂ – Cobalamin
Function
Like folate, Vitamin B₁₂ is necessary for red blood cell formation and DNA synthesis. It also assists in neurological function.
Forms of Vitamin B₁₂
The form that naturally occurring vitamin B₁₂ is tied to proteins in foods and needs to be broken down to get “free” vitamin B₁₂. Once it is in free form, it can bind to a substance in the body called intrinsic factor and be absorbed. Some people do not produce intrinsic factor and need to consume the free form of vitamin B₁₂ to meet their needs.
Fortified foods and supplements use the free form of vitamin B₁₂ and therefore get to skip the break down step.
The prescription form vitamin B₁₂ is known as cyanocobalamin and sometimes hydroxocobalamin. These forms are often given in the form of a shot and should be administered by a medical professional.
Recommended Intake and Deficiency
The recommended daily intake of vitamin B₁₂ for men and women 14 years and older is 2.4mcg. Most people in the US meet these recommendations through a normal, varied diet.
Those who are at highest risk of deficiency include the elderly and people with pernicious anemia. People with pernicious anemia lack intrinsic factor, a substance that allows the body to absorb vitamin B₁₂.
The most common presentation of B₁₂ deficiency is megaloblastic anemia, a type of anemia where the red blood cells are too large and quantity is low. Other signs and symptoms of B₁₂ deficiency include imbalance, depression, poor memory, and soreness of the mouth and tongue.
Tolerable Upper Level Intake
There are currently no established ULs set for vitamin B₁₂ due to its low potential for toxicity.
Drug-Nutrient Interactions with B₁₂
There are a handful of medications known to interact with B₁₂ in the body. Talk with your doctor about if you should be taking a B₁₂ supplement and how it may interact with any current medications.
Examples of medications that interact with vitamin B₁₂ are listed below.
- Chloramphenicol (antibiotic)
- Proton pump inhibitors (treatment of gastroesophageal reflux)
- H2 receptor antagonists (treatment of peptic ulcer disease)
- Metformin (treatment of diabetes)
Sources
Vitamin B₁₂ is mostly found in animal-based products unless fortified in plant-based foods, such as breakfast cereals. Below is a table of food sources for vitamin B₁₂.
Table 11. Food sources of vitamin B12
| Food | Micrograms (mcg) per serving |
| Clams, cooked, 3 ounces | 84.1 |
| Salmon, sockeye, cooked, 3 ounces | 4.8 |
| Nutritional yeast, fortified with 100% Daily Value for vitamin B₁₂, 1 serving | 2.4 |
| Milk, low-fat, 1 cup | 1.2 |
| Breakfast cereals, fortified with 25% Daily Value for vitamin B₁₂, 1 serving | 0.6 |
Why is vitamin B₁₂ important for kidney disease?
There is a high prevalence of vitamin B₁₂ deficiency in CKD patients and is even more common in CKD patients 60 years and older.
Studies have shown that B₁₂ supplementation can reduce homocysteine levels, a risk factor for cardiovascular disease, in patients with CKD but it is less effective when compared to those with normal kidney function.
Since the best sources of vitamin B12 come from animal-based foods, something that is typically restricted in the diet of CKD patients, it is important to seek out kidney-friendly food sources of B₁₂ to make sure you are meeting the daily recommendations and prevent B₁₂ anemia.
It may be beneficial to talk to your doctor about getting your B₁₂ levels tested in order to prevent anemia. Always consult your medical provider before starting a new supplement routine.
Vitamin C – Ascorbic Acid
Function
Vitamin C is best known for its “immune boosting” properties and is often marketed as such. While vitamin C does help to support the immune system by acting as an antioxidant, many don’t know the other critical roles it plays in the body.
Beyond being a strong antioxidant, vitamin C also assists in wound healing through collagen production and helps to maximize iron absorption in the body.
Forms of Vitamin C
When looking for supplements, you will likely see vitamin C have ascorbic acid written below it or on the ingredients list. Ascorbic acid is the same form of vitamin C you would find in your orange juice.
Other forms of vitamin C, though less common, are sodium ascorbate and calcium ascorbate.
Although, if you are buying kidney-specific renal vitamins, you will probably find that they contain little to none vitamin C content. The next section explains why.
Recommended Intake and Deficiency
The recommended daily allowance for vitamin C is 75mg per day for men 14-18 years and 90mg for men 19 years and older. For women, it’s 65mg ages 14-18 years and 75mg 19 years and older.
Vitamin C deficiency is uncommon in the US and has rarely been seen in any developed country since the 18th century.
Severe vitamin C deficiency presents itself as scurvy. The most notable sign of scurvy is bleeding and inflammation of the gums. Other symptoms include poor wound healing, joint pain, petechiae, and loosening or loss of teeth.
Iron deficiency anemia may also occur due to vitamin C’s prominent role in proper iron absorption in the body.
Those who are at a higher risk for deficiency include:
- Smokers
- Infants fed cow’s milk
- Individuals with limited food variety
- Individuals with malabsorption and certain chronic diseases
Tolerable Upper Level Intake
Vitamin C is considered to have a low risk for toxicity and is not typically of concern to the average, healthy person to overconsume.
However, to those living with CKD, the amount of vitamin C you should consume should be discussed with your doctor as many studies suggest that supplementation can lead to more incidents of kidney stones.
Drug-Nutrient Interactions with Vitamin C
Vitamin C supplements have been known to react with several medications, including, but not limited to:
- Chemotherapy and radiation
- Statins (ZocorⓇ)
Sources of Vitamin C
The primary sources of vitamin C are found in fruits and vegetables. Oftentimes we think of oranges when it comes to vitamin C, but there are many other ways to get your daily dose in!
See Table 1 for a list of food sources for vitamin C.
Table 1. Food Sources of Vitamin C
| Food | Milligrams (mg) per serving |
| Red Pepper, sweet, raw, ½ cup | 95 |
| Orange Juice, ¾ cup | 93 |
| Orange, 1 medium | 70 |
| Kiwifruit, 1 medium | 64 |
| Broccoli, cooked, ½ cup | 51 |
| Cantaloupe, ½ cup | 29 |
| Cauliflower, raw, ½ cup | 26 |
Why is Vitamin C Important for Kidney Disease?
Supplementing with vitamin C in high amounts is often discouraged for those with CKD and is not typically one of the recommended vitamins for kidneys. Consequently, this suggestion can be confusing to many, as we typically hear all our lives about how beneficial vitamin C is to our health.
Since vitamin C can be turned into oxalate in the body, there is concern as to what its contribution may be in kidney stone formation. One study where participants had an intake of 1000mg of vitamin C per day showed an increase of oxalate excretion, a common way to measure oxalate levels, by 20 percent.
Higher oxalate levels can lead to more frequent stone formation. For someone with CKD, it is important to lower your risk of kidney stones as much as possible. You can refer to my previous article, Tips on How to Prevent Kidney Stones Naturally, to learn more.
Cooking with Water-Soluble Vitamins
If fat-soluble vitamins absorb best in the body with high fat meals, it makes sense if you are thinking that you should consume a tall glass of water with your next water-soluble vitamin rich meal.
While staying hydrated is always important, know that you don’t have to take in any excess water than normal just because you are having a meal high in water-soluble vitamins. This is especially important if you are on fluid restriction as you don’t want to use up half your daily allotment just to eat one meal!
Here are some simple ways you can help to maximize the water-soluble content in food during the cooking process.
Minimize the amount of water used
This helps prevent the amount of water that the vitamins within the food can leach out into, which is especially important if you plan on discarding the water after cooking. Try roasting or broiling over steaming or blanching.
Cut your fruits & vegetables into larger pieces
Where there is surface area, there is a chance of nutrients to “leak” out. The larger the pieces, the less total surface area there is to be exposed when compared to dicing into small bits. Consider this especially when using cooking methods involving water.
Cook first, then cut
Going off of the previous tip, you can save more vitamin content by cooking the vegetable whole first, then cutting it to the desired size afterwards.
Go low and slow
If you are preparing a meat dish, such as pork, high in various B vitamins, you can help to preserve that vitamin content by opting for methods that cook at a lower temperature for a longer amount of time, such as braising.
How to Choose Vitamins for Kidneys
Third Party Verification
The FDA is not responsible for reviewing the safety and effectiveness of supplements before they are marketed. However, all supplement manufacturers are required to follow Current Good Manufacturing Practices which sets certain standards for products all across the board.
Even with these standards in place, looking for a third party verification label is a good way to ensure you know what you are buying. This means that a separate, non-affiliated company comes to verify the potency and practices used to create the product at the manufacturing site.
Below are some easy-to-spot images of popular third-party testers that you can look for when purchasing supplements.
Looking for Additives
If you follow a strict vegetarian or vegan diet, you will also want to look for the type of coating a supplement has. Many use animal-derived ingredients for their capsules.
Supplements may also have added sweeteners or come in a “gummy” form that you may want to avoid.
My Recommendations
It’s easy to become overwhelmed by which vitamins for kidneys to get, whether it’s online and in stores. If you’re looking for a multivitamin that has everything you need all in one, you can find my preferred brands on my Amazon shop* for reputable brands that I trust.
For those in the United States, I have a Fullscript dispensary* in which you can receive 15% off of your supplement order!
These multivitamins contain vitamins and minerals in appropriate doses for many CKD patients, however, remember to always consult with your medical provider before starting a new supplement routine.
Summary
Water-soluble vitamins provide a wide range of benefits whether they are coming from food or supplement sources. They are vital nutrients that help your body carry out necessary bodily functions.
Many people with kidney problems may find themselves deficient in many B vitamins as the main dietary source comes from animal-based foods, something that is often restricted in the diet for those with CKD.
As has been noted, the one water-soluble vitamin that is typically not recommended for CKD patients is vitamin C, as it has been linked to higher incidences of kidney stones.
All things considered, everyone with CKD has different needs when it comes to vitamins for the kidneys. It is important to talk with your medical provider before changing or starting a new supplement routine. You could start the conversation by asking about getting a micronutrient test done, like Spectracell, to see what you are deficient in.
There are a handful of multivitamins formulated with CKD patients in mind, but you can find my personal recommendations here and you will receive 15% off your order!
