Definition

What Is Chronic Kidney Disease?

Chronic kidney disease (CKD) is the gradual, progressive loss of kidney filtration capacity over months to years. The kidneys, which filter about 150 quarts (140 liters) of blood daily¹⁹ and remove metabolic waste, electrolytes, fluid and toxins, lose nephrons (functional units) faster than they can be replaced, eventually leading to retention of waste products, fluid overload, electrolyte imbalances and systemic toxicity.

CKD is classified into 5 stages based on estimated glomerular filtration rate (eGFR¹). Stages 1 to 3 are often asymptomatic; stages 4 to 5 represent advanced disease requiring intensive management or renal replacement therapy (dialysis or transplant). Treating the underlying causes can slow the move from early to late CKD².

Most CKD cases are driven by diabetes, hypertension or both, making CKD largely a downstream consequence of metabolic dysfunction. The gut-kidney axis is increasingly recognized: uremic toxins that start from gut bacteria (indoxyl sulfate, p-cresyl sulfate, TMAO) are being studied for links with faster kidney decline and cardiovascular complications²⁰.

⚠️ CKD is often called a "silent disease": most people in the early stages have no symptoms, and many have none until their kidney disease is advanced¹⁷. ~9 in 10 adults with CKD don't know they have it. Annual screening with eGFR + urine albumin is critical for anyone with diabetes, hypertension, family history or age 60+.

A smooth normal kidney beside a shrunken, damaged kidney with a lumpy surface, ringed by four icons labeled anemia, fatigue, heart disease and high blood pressure

Stages of Chronic Kidney Disease

Stages 1 to 2 (Early)

eGFR ≥60 mL/min/1.73m² with kidney damage markers (proteinuria¹, abnormal imaging). Asymptomatic, and the window where slowing progression matters most. Lifestyle and dietary interventions here have the most leverage: aggressive blood pressure control and glucose management can slow progression. Established scarring does not reverse, so the goal is preserving what is there².

Stage 3 (Moderate)

eGFR 30 to 59. Subtle symptoms emerge: fatigue, mild swelling, frequent urination. Complications begin: anemia, mineral-bone disease, mild metabolic acidosis. Nephrology referral indicated. Phosphorus and potassium management starts to matter. Cardiovascular risk climbs sharply.

Stages 4 to 5 (Advanced)

eGFR <30. Significant symptoms: marked fatigue, edema, uremic symptoms (nausea, itching, metallic taste). Stage 5 (eGFR <15) is kidney failure: dialysis or a transplant is planned, and dialysis starts on symptoms and overall assessment, often at an eGFR of 5 to 10. Even at this stage, nutrition supports symptom control and slows residual function loss.

Treatment Comparison

Conventional and Holistic Treatment for Chronic Kidney Disease

🌿 HOLISTIC

💊 CONVENTIONAL

🌿

Holistic / Functional Approach

Plant-forward Mediterranean diet, controlled protein, gut microbiome support, blood sugar & BP control, anti-inflammatory nutrients

Slowing Progression

Plant-forward eating lower in animal protein and sodium is associated with slower progression, adapted for potassium and phosphorus by stage⁷

Key Levers

Sodium <2 g/day, protein about 0.8 g/kg/day in CKD stages 3 to 5 (lower only under close supervision), plant-dominant sources⁹

Timeline

Blood pressure and albuminuria respond to treatment first; the longer-term goal is slower eGFR decline, not reversal²

Advantage

Works on diet, blood pressure, blood sugar and weight alongside medication

Full Holistic Approach Includes

Plant-dominant Mediterranean diet: higher plant intake is linked with slower progression in observational studies¹⁴; your renal dietitian sets the balance around your potassium and phosphorus results.
Strict sodium restriction <2 g/day (some sources advocate <1.5 g), a major dietary lever for BP and proteinuria reduction. Hidden sodium in processed foods is the main source.
Controlled protein intake, about 0.8 g/kg/day in CKD 3 to 5 without dialysis, lower only under close supervision⁹. Excess protein burdens nephrons.
Bicarbonate/alkali support: metabolic acidosis accelerates CKD progression. Fruits and vegetables provide natural alkali; oral sodium bicarbonate, prescribed when blood bicarbonate is low (typically 1 to 2 g twice a day), can slow progression; it adds sodium, so take it only as prescribed.
Gut microbiome support: prebiotic fiber (resistant starch, inulin), probiotics and less animal protein may lower production of uremic toxins (indoxyl sulfate, p-cresyl sulfate, TMAO).
Aggressive blood pressure control: a target your nephrology team sets; KDIGO suggests a systolic pressure under 120 mmHg where tolerated²¹. Dietary approaches (DASH-adapted for kidney) and hibiscus tea can help. Two common blood pressure tips need care in CKD: magnesium supplements and beets. Magnesium is cleared by the kidneys and accumulates as function declines, so supplements need your nephrology team's agreement and are generally avoided in later stages. Beets are high in potassium, and in CKD potassium is the mineral that can cause harm fastest; what is safe depends on your stage and your latest blood test results⁴.
Blood sugar optimization if diabetic, A1c <7% or the target your care team sets for you. SGLT2 inhibitors slow kidney disease progression with or without diabetes¹⁰; discuss with nephrologist.
Phosphorus management: limit processed foods (high inorganic phosphate additives) more strictly than naturally phosphorus-rich foods (the additive form is far more completely absorbed).
Omega-⁠3 EPA/DHA (2 to 3 g/day), studied for proteinuria and cardiovascular risk in CKD; a benefit is not established.
Vitamin D repletion: most CKD patients are deficient; correcting a deficiency is reasonable. The activated prescription form may be needed in stage 4 to 5.

⚠️ Critical: CKD nutrition requires individualization based on stage, lab values (potassium, phosphorus, bicarbonate) and comorbidities. Work with a renal-trained dietitian. Never make dramatic protein, potassium or phosphorus changes without lab guidance.

💊

Conventional / Medical Approach

ACE inhibitors/ARBs, SGLT2 inhibitors, mineralocorticoid antagonists, phosphate binders, EPO, dialysis

First-Line

ACE inhibitors or ARBs for albuminuria >30 mg/g, even without high blood pressure (recommended with diabetes or above 300 mg/g, suggested otherwise)⁹

SGLT2 Inhibitors

In trials, SGLT2 inhibitors reduced the risk of kidney disease progression by 37%, with similar effects in people with and without diabetes¹⁰

Symptom Management

EPO for anemia, phosphate binders, vitamin D analogs, sodium bicarbonate

End-Stage

Dialysis (hemodialysis or peritoneal dialysis) or kidney transplant, started on symptoms and overall assessment, often at eGFR 5 to 10; planning starts below 15 to 20 ⁹

Conventional Approach Includes

ACE inhibitors or ARBs, which reduce intraglomerular pressure and proteinuria and slow progression. Monitor potassium and creatinine.
SGLT2 inhibitors: landmark trials (CREDENCE, DAPA-CKD, EMPA-KIDNEY) show kidney protection beyond diabetes. Now indicated for CKD regardless of diabetes status.
Nonsteroidal mineralocorticoid antagonists, newer; reduce cardiovascular events and CKD progression in diabetic CKD.
GLP-⁠1 agonists, emerging kidney protection beyond weight/glucose effects.
Phosphate binders, needed when serum phosphorus rises in CKD 4 to 5.
Erythropoiesis-stimulating agents (EPO), for anemia of CKD when hemoglobin drops below 10 g/dL.
Active vitamin D, for secondary hyperparathyroidism in CKD 4 to 5.
Dialysis or transplant, planned once eGFR falls below 15 to 20; dialysis starts on symptoms and overall assessment, often at an eGFR of 5 to 10.

⚠️ Important: Most CKD medications require ongoing lab monitoring. ACE inhibitors and ARBs can raise potassium (hyperkalemia) and creatinine. SGLT2 inhibitors increase the risk of yeast infections and, rarely, ketoacidosis with normal blood sugar (euglycemic DKA). Never adjust doses without prescriber guidance.

Nutritional Strategy

Diet for Chronic Kidney Disease

The CKD diet evolves with stage. Early CKD focuses on prevention (DASH/Mediterranean); late CKD requires careful management of protein, sodium, potassium and phosphorus based on labs.

Foods that protect kidney function, and what to limit

What to eat or do	Details
✅ Prioritize These:
Plant-Based Proteins	Legumes, tempeh, lentils. Plant foods contain phosphorus in a less absorbable form⁴, and eating patterns higher in plants are linked with a lower risk of CKD and slower progression¹⁴. How much suits you depends on your potassium and phosphorus results.
Vegetables & Fruits	Especially berries, apples, cabbage, cauliflower, peppers, leafy greens (in moderation if you are on a potassium restriction). Provide natural alkali to counter metabolic acidosis, fiber for the microbiome and antioxidants for kidney protection.
Omega-⁠3-⁠Rich Fish (2x/week)	Wild salmon, sardines, Atlantic mackerel. Their EPA/DHA are studied for proteinuria and heart risk in CKD, though a benefit is not established. Smaller fish are lower in mercury, important when kidney clearance is reduced.
Olive Oil & Healthy Fats	Mediterranean staple. Anti-inflammatory and supports cardiovascular health (cardiovascular risk rises as kidney function falls¹⁶). It provides calorie density without protein burden, useful for maintaining weight in advanced CKD.
❌ Limit or Eliminate:
Sodium (<2 g/day)	A major dietary lever. Hidden sodium in bread, deli meats, canned soups, restaurant food and condiments adds up fast. Read labels: anything >200 mg sodium per serving is high. Cook at home to control intake.
Excess Animal Protein	Red meat especially. Generates acid load, uremic toxin precursors (TMAO from carnitine, indoxyl sulfate from tryptophan via gut bacteria). Limit red meat to 1 to 2 servings a week in CKD stage 3 and above and replace some animal protein with plant proteins; keep total protein at the target your renal dietitian sets.
Ultra-Processed Foods (Phosphate Additives)	Inorganic phosphate additives in processed foods (look for "PHOS" on labels) are far more completely absorbed than natural phosphorus. Sodas, processed meats, fast food, frozen meals. A major dietary phosphorus source, and the most avoidable.
Sugar & Refined Carbs	Drives diabetes/insulin resistance (the #1 cause of CKD), accelerates inflammation and promotes AGE (advanced glycation end-product) formation that directly damages renal microvasculature.

Supplement Protocol

Evidence-Based Supplements for Chronic Kidney Disease

CKD supplementation requires special caution: failing kidneys can't clear excess nutrients normally. Always coordinate with your nephrologist; some supplements are dangerous in advanced CKD.

Supplement	What it is for	Typical range	Timing	Notes & cautions
Omega-⁠3 EPA/DHA	Studied for proteinuria and cardiovascular risk in CKD; that it slows progression is not established. Anti-inflammatory and lipid-modulating effects.	2 to 3 g combined EPA+DHA/day	With largest fat meal	Triglyceride form, third-party tested. Discontinue 1 week before surgery (antiplatelet effect). In heart trials, fish oil supplements raised the risk of atrial fibrillation, an irregular heartbeat, more so above 1 g a day¹⁸, so check this dose with your clinician first.
Vitamin D3	Low vitamin D is common in CKD. Kidneys convert 25-⁠OH-D to active 1,25-⁠OH-D, and this conversion falls as CKD progresses. Correcting a deficiency is reasonable; benefits for immunity or blood pressure are not established.	D3: Test 25-⁠OH-D first and set the dose with your clinician	With fat meal	Test 25-⁠OH-D. In CKD 4 to 5, the activated prescription form is often needed.
Sodium Bicarbonate (alkali)	Metabolic acidosis (low serum bicarbonate) accelerates CKD. In the open-label UBI trial in 740 people with CKD stages 3 to 5, treating low bicarbonate cut doubling of creatinine from 17.0% to 6.6% over about 3 years, and fewer started dialysis or died¹⁵.	0.5 to 1.0 mEq/kg/day (typically 1 to 2 g sodium bicarbonate 2x/day)	Between meals	Prescribed when bicarbonate <22. Adds sodium load; monitor BP. Capsules better tolerated than powder.
CoQ10 (Ubiquinol)	Mitochondrial cofactor. CKD impairs mitochondrial function in kidneys and heart. Small trials report lower oxidative stress markers; effects on kidney function or the heart are not established.	100 to 200 mg/day (ubiquinol)	With fat meal	Statins lower blood CoQ10; a benefit from supplementing is not established. Ubiquinol form better absorbed in CKD.
Curcumin (Turmeric Extract)	Anti-inflammatory, antifibrotic. Small RCTs in CKD show reduced proteinuria, inflammatory markers and oxidative stress.	500 to 1,000 mg curcumin	With food, 2x/day	Avoid with anticoagulants. Liver injury has been reported mainly with high-dose, high-absorption formulations such as those with piperine, so stop and seek advice if you notice dark urine or yellowing skin.
Probiotic + Prebiotic (Synbiotic)	Gut dysbiosis in CKD increases uremic toxin (indoxyl sulfate, p-cresyl sulfate) production. Specific probiotics + prebiotic fiber may reduce these toxins; effects on clinical outcomes are not established. Strongest evidence: Lactobacillus, Bifidobacterium strains with resistant starch.	Multi-strain 25 to 50 billion CFU + 5 to 10 g resistant starch	With meals	Eat fermented foods alongside. Adjust prebiotic fiber gradually to avoid gas. Avoid high-potassium prebiotic foods if hyperkalemic.
L-Carnitine (in dialysis patients)	Dialysis depletes L-carnitine; supplementation may reduce dialysis-associated symptoms (fatigue, muscle weakness, cardiac dysfunction). Mixed evidence; NOT for pre-dialysis CKD (could increase TMAO).	500 to 1,000 mg/day (dialysis patients only)	Post-dialysis days	Discuss with nephrologist. TMAO concerns in non-dialysis CKD.
Iron + B-Vitamins (for CKD anemia)	Iron-restricted erythropoiesis is common in CKD. Oral iron may be poorly absorbed; IV iron often needed. B12 and folate support red cell production.	Per nephrologist (often IV iron in clinic + oral B-complex)	n/a	Coordinate with nephrology: iron repletion requires monitoring ferritin and transferrin saturation. Excess iron is harmful.

References & Evidence Notes

Each numbered entry below is either a source you can follow or a note setting out what the evidence does and does not support. Both are numbered together so the markers in the text line up.

Last reviewed October 20, 2026. Supplement entries are cross-checked against the NIH National Center for Complementary and Integrative Health and the Linus Pauling Institute Micronutrient Information Center.⁸ This page needs a stronger caution than most, because in kidney disease several ordinary supplements become genuinely dangerous. Do not start any supplement without your nephrology team. Potassium can cause fatal arrhythmias and is present in supplements, salt substitutes and many healthy foods. Magnesium is cleared by the kidneys and accumulates. High-dose vitamin C is converted to oxalate and can deposit in the kidney. Many herbal products are directly nephrotoxic, and some imported products have been adulterated with aristolochic acid, a known cause of kidney failure. NSAIDs including ibuprofen and naproxen should generally be avoided. What is safe depends on your stage and your latest blood test results, which is why a renal-trained dietitian is not an optional refinement here. Nothing on this page reverses established kidney damage; the realistic and worthwhile goal is slowing progression.

On staging and risk: in a meta-analysis of general population cohorts with more than 1.2 million people, an eGFR below 60 and an albumin-to-creatinine ratio of 10 mg/g or more each independently predicted death, including cardiovascular death, which supports using both measures to define and stage CKD, PubMed 20483451. In 1.1 million adults, cardiovascular events rose as eGFR fell, PubMed 15385656, and in 27,998 people followed for 5 years, death was far more common than dialysis at every stage, PubMed 15037495. Diabetes and high blood pressure are the most common causes (note 12). ↩
On what can and cannot change: NIDDK advises that advanced, long-lasting CKD typically cannot be undone, that CKD tends to get worse over time, and that managing blood pressure, blood glucose and weight can help slow its progression and prevent or delay kidney failure, NIDDK, what is CKD and managing CKD. SGLT2 inhibitors reduced the risk of kidney disease progression by 37% in people with and without diabetes (note 10). Claims that diet restores lost kidney function should be treated with suspicion; slowing progression is the goal the evidence supports. ↩
On protein: a Cochrane review of 17 studies in 2,996 people found that a low protein diet probably makes little or no difference to deaths and may make little or no difference to reaching kidney failure compared with a normal intake, while a very low protein diet probably reduces the number who reach kidney failure; effects on body weight were uncertain, PubMed 33118160. KDIGO suggests 0.8 g/kg a day in stages 3 to 5, with very low protein diets only under close supervision (note 9). Protein targets are set with a renal dietitian, not self-directed. ↩
On the minerals that can cause harm quickly: hyperkalemia causes cardiac arrhythmias and can be fatal; risk rises as eGFR falls and with RAS-blocking drugs. Potassium is present in salt substitutes, many supplements and foods usually considered healthy, including beets, bananas, potatoes, tomatoes and dried fruit. Salt substitutes are the easiest of these to miss, and a review of 32 hypertension and 14 kidney guidelines found the advice on them incomplete and inconsistent, so do not assume a general healthy-eating recommendation was written with your kidneys in mind, PubMed 38284271. Phosphorus restriction becomes relevant in later stages, and the form matters as much as the amount: phosphorus in plant foods is less available for absorption than phosphorus from animal protein or from the inorganic phosphate additives in processed food, PubMed 34113962. Magnesium is renally excreted and accumulates as function declines, so magnesium supplements are generally avoided in advanced CKD. None of these is a matter of general dietary principle; they depend on stage and current blood test results. ↩
On supplements and herbs that cause direct harm: high-dose vitamin C is metabolized to oxalate, and oxalate nephropathy is a recognized risk of high-dose intravenous vitamin C, particularly with very large or repeated doses, PubMed 41815850. Aristolochic acid, found in some traditional herbal preparations and as an adulterant, causes irreversible kidney failure, and is one of the established contributors to upper tract urothelial carcinoma, PubMed 42588616. Star fruit is both neurotoxic and nephrotoxic in kidney failure, PubMed 33693950. Creatine raises serum creatinine, which confounds monitoring even where it is not itself harmful. Fat-soluble vitamins and vitamin A in particular can accumulate. ↩
On medicines to be careful with: NIDDK warns that NSAIDs, found in common pain relievers and cold medicines, can damage the kidneys and cause acute kidney injury, especially with kidney disease, diabetes or high blood pressure; that a provider may lower a dose, space doses out, stop a medicine or switch it as kidney disease gets worse; and that your pharmacist and every provider need to know all the medicines, over-the-counter products, vitamins and supplements you take, NIDDK, managing CKD. Tell any prescriber, including dentists, that you have kidney disease. ↩
On the things that genuinely help and are often missed: in a randomized trial of 134 adults with advanced CKD and low bicarbonate, oral sodium bicarbonate slowed the decline in kidney function and improved nutritional status, PubMed 19608703; NIDDK lists anemia among the complications of CKD and tiredness among the symptoms of advanced disease, NIDDK; and a meta-analysis of observational studies linked plant-based eating with a lower risk of CKD and slower progression, PubMed 40081608, adapted for potassium and phosphorus by stage. Limiting protein is the opposite of the advice for age-related muscle loss, and many older adults have both; see the sarcopenia guide, and take your protein target from your kidney team rather than from either page alone. ↩
National Center for Complementary and Integrative Health (NIH), nccih.nih.gov, and the Linus Pauling Institute Micronutrient Information Center, lpi.oregonstate.edu/mic. ↩
On the KDIGO 2024 guideline for chronic kidney disease: it suggests a protein intake of 0.8 g/kg body weight per day in adults with CKD stages G3 to G5, with very low protein diets only under close supervision, and sodium below 2 g per day. It recommends starting an ACE inhibitor or ARB for albuminuria in the A3 range without diabetes and in the A2 and A3 ranges with diabetes, suggests it for the A2 range without diabetes, and applies these even in the absence of high blood pressure. It advises starting dialysis on a composite assessment of symptoms, signs and laboratory results, which often but not invariably happens at a GFR between 5 and 10, and planning for transplant or dialysis access when GFR is below 15 to 20, KDIGO, 2024. ↩
On SGLT2 inhibitors and kidney progression: a 2022 collaborative meta-analysis of 13 large placebo-controlled trials in 90,409 participants found that SGLT2 inhibitors reduced the risk of kidney disease progression by 37%, with similar effects in people with and without diabetes, PubMed 36351458. ↩
On how common chronic kidney disease is: CDC estimates that 14% of US adults, about 37 million people, have CKD, including 38% of adults with diabetes, 21% of adults with high blood pressure and 34% of adults aged 65 or older, and that about 9 in 10 adults with CKD do not know they have it, CDC, Chronic Kidney Disease in the United States. ↩
On what causes chronic kidney disease: the most common causes in adults are diabetes and high blood pressure; others include acute kidney injury, glomerular diseases such as IgA nephropathy, autoimmune disease such as lupus, drugs toxic to the kidneys, polycystic kidney disease and rare genetic conditions, kidney stones with complications, metabolic syndrome and severe obesity, NIDDK, Causes of Chronic Kidney Disease in Adults. ↩
On monitoring in chronic kidney disease: the KDIGO 2024 guideline advises checking blood pressure, creatinine and potassium within 2 to 4 weeks of starting or raising an ACE inhibitor or ARB, continuing it unless creatinine rises by more than 30% within 4 weeks, and treating the early reversible fall in eGFR with an SGLT2 inhibitor as no reason to stop. It advises measuring eGFR and urine albumin at least yearly, reviewing a fall in eGFR of more than 20% or a doubling of albumin, screening nutrition twice a year from stage G4, and sick day guidance to pause some medicines during a dehydrating illness. Its signs of kidney failure include confusion and other neurological symptoms of uremia, loss of appetite, itching that does not respond to treatment, inflammation around the heart, and fluid or blood pressure that cannot be controlled, KDIGO, 2024. ↩
On plant-based eating and kidney disease: a meta-analysis of studies in 121,927 adults followed for an average of 11.2 years found plant-based diets were associated with a 26% lower incidence of chronic kidney disease, with higher intakes linked to lower risk and slower progression in a dose-dependent way, while unhealthy plant-based diets may not protect the kidneys. These are associations from observational studies, PubMed 40081608. ↩
On treating metabolic acidosis: in the open-label UBI trial, 740 people with CKD stages 3 to 5 and low bicarbonate were randomized to sodium bicarbonate or standard care for 36 months; doubling of creatinine occurred in 6.6% against 17.0%, and fewer started dialysis (6.9% against 12.3%) or died (3.1% against 6.8%), PubMed 31598912. ↩
On kidney function and heart risk: in 1,120,295 adults followed for a median of 2.8 years, the risk of cardiovascular events rose as eGFR fell, to 1.4 times at an eGFR of 45 to 59, 2.0 times at 30 to 44, 2.8 times at 15 to 29 and 3.4 times below 15, after adjustment, PubMed 15385656. ↩
On how CKD shows itself and what slows it: NIDDK explains that most people in the early stages of CKD have no symptoms and many have none until the disease is advanced, and that managing blood pressure, blood glucose and weight can help slow its progression and prevent or delay kidney failure, NIDDK, what is chronic kidney disease. ↩
Gencer B, Djousse L, Al-Ramady OT, Cook NR, Manson JE, Albert CM. Effect of long-term marine omega-⁠3 fatty acids supplementation on the risk of atrial fibrillation in randomized controlled trials of cardiovascular outcomes: a systematic review and meta-analysis. Circulation. 2021;144(25):1981-⁠1990. PubMed 34612056. Seven trials with 81,210 people followed for about 5 years: omega-⁠3 supplements were linked to a higher risk of atrial fibrillation (hazard ratio 1.25), more so in trials of more than 1 g a day (1.49), and the risk rose with each additional gram. ↩
On how much blood the kidneys filter: NIDDK states that in a single day the kidneys filter about 150 quarts of blood, of which only 1 to 2 quarts become urine, NIDDK, your kidneys and how they work. ↩
Lim YJ, Sidor NA, Tonial NC, Che A, Urquhart BL. Uremic toxins in the progression of chronic kidney disease and cardiovascular disease: mechanisms and therapeutic targets. Toxins (Basel). 2021;13(2):142. PubMed 33668632. A review: uremic toxins build up as kidney function falls, and their buildup is associated with CKD progression and with cardiovascular disease. It covers indoxyl sulfate, p-cresyl sulfate and TMAO among others and notes that few of these toxins have yet been studied in depth. ↩
Cheung AK, et al. Executive summary of the KDIGO 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease. Kidney Int. 2021;99(3):559-⁠569. PubMed 33637203. Drawing mainly on the SPRINT trial, the guideline proposes a systolic blood pressure target below 120 mmHg, measured with standardized office readings, for most people with CKD not on dialysis; children and kidney transplant recipients are the exceptions. ↩

Symptom	What happens
Fluid & Filtration
Changes in Urination	Foamy urine (proteinuria), blood in urine (hematuria), nocturia (waking to urinate), decreased urine volume or paradoxically increased volume in early stages. Often the first observable sign, but easily dismissed.
Swelling (Edema)	Failing kidneys retain sodium and water, so fluid accumulates in ankles, feet and around the eyes (especially in the morning). Severe cases develop pulmonary edema (shortness of breath when lying flat).
High Blood Pressure (New or Worsening)	CKD both causes and is caused by hypertension. Newly diagnosed or harder-to-control BP in someone with risk factors should trigger kidney function testing: the kidneys regulate fluid volume and renin output, both critical to BP.
Cold Intolerance & Pale Skin	Failing kidneys produce less erythropoietin → anemia → reduced oxygen-carrying capacity → coldness, pallor. CKD anemia is a major driver of fatigue and is often underdiagnosed before stage 3 to 4.
Systemic & Uremic
Persistent Fatigue	Multifactorial: anemia (low erythropoietin), uremic toxin buildup, sleep disruption, metabolic acidosis, mitochondrial dysfunction. CKD fatigue is profound and unresponsive to sleep, a key marker that quality of life is being compromised.
Nausea, Vomiting & Loss of Appetite	Uremia (waste buildup) suppresses appetite and causes nausea, often worst in the morning. Many CKD patients develop unintentional weight loss and muscle wasting that paradoxically worsens prognosis.
Metallic Taste & Bad Breath (Uremic Fetor)	Urea breakdown in saliva produces ammonia, which creates a metallic taste and ammonia-like breath. Foods (especially red meat) start tasting wrong. Powerful subjective marker of advanced uremic toxin retention.
Restless Legs, Muscle Cramps & Itching	Mineral imbalances (calcium, phosphorus, magnesium), uremic toxin buildup and peripheral neuropathy cause restless legs at night, severe muscle cramps and persistent generalized itch (uremic pruritus). These late-stage symptoms severely impact quality of life.

Cause	How It Contributes to Chronic Kidney Disease	What Helps
Diabetes	High blood sugar damages the kidneys' filters over time and lets protein the body needs leak into the urine¹². About 4 in 10 US adults with diabetes have CKD¹¹.	Blood sugar control and cutting sugar and refined carbohydrate (Nutritional Strategy); an SGLT2 inhibitor, which in trials lowered the risk of kidney disease progression by 37% with or without diabetes¹⁰ (conventional care)
High blood pressure	High pressure damages the blood vessels of the kidneys' filtering system, and the extra fluid that damaged kidneys hold on to raises pressure further, a self-reinforcing cycle¹².	Sodium below 2 g a day⁹ and less processed food (Nutritional Strategy); an ACE inhibitor or ARB when albumin is found in the urine, even without high blood pressure⁹ (conventional care)
Glomerular and autoimmune disease	Conditions such as IgA nephropathy, membranous nephropathy, focal segmental glomerulosclerosis and lupus damage the filters directly¹².	Diagnosis and disease-specific treatment from a nephrologist (conventional care); no diet treats these conditions
Inherited kidney disease	Polycystic kidney disease and rarer genetic conditions such as Alport syndrome cause CKD¹².	Specialist care, and screening with eGFR and urine albumin when there is a family history, as the Definition section advises (conventional care)
Kidney injury from medicines and herbs	Drugs that are toxic to the kidneys and episodes of acute kidney injury can lead to CKD¹². NSAID pain relievers can damage the kidneys and cause acute kidney injury, especially with kidney disease⁶, and aristolochic acid, found in some herbal preparations, causes irreversible kidney failure⁵.	Avoid NSAIDs and tell every prescriber, dentist and pharmacist that you have kidney disease⁶; clear any supplement with your nephrology team first (Supplement Protocol)
Severe obesity and metabolic syndrome	Both are listed among the other causes of CKD in adults¹², and both travel with diabetes and high blood pressure.	A plant-forward, lower-sodium eating pattern adapted to your stage and blood test results (Nutritional Strategy)

Test	What it shows
Essential Labs (Annual)
eGFR (Estimated Glomerular Filtration Rate)	Calculated from serum creatinine, age, sex and (formerly) race. Normal: ≥90. Stage 1 to 2: ≥60 with damage markers. Stage 3a: 45 to 59. Stage 3b: 30 to 44. Stage 4: 15 to 29. Stage 5: <15. Modern CKD-EPI 2021 formula removed race coefficient for accuracy.
Urine Albumin-to-Creatinine Ratio (uACR)	Detects kidney damage BEFORE eGFR declines. Normal: <30 mg/g. Moderately increased (microalbuminuria): 30 to 300. Severely increased: >300. Microalbuminuria is the earliest detectable kidney injury, and is also a powerful cardiovascular risk marker.
BUN, Creatinine, Electrolytes	Blood Urea Nitrogen, creatinine, sodium, potassium, calcium, phosphorus, bicarbonate⁷. Trends matter more than single values. Rising creatinine, hyperkalemia, hyperphosphatemia or acidosis (low bicarbonate) all signal progressing CKD.
Advanced Workup (As Indicated)
Cystatin C	Alternative to creatinine, not affected by muscle mass. Especially useful in elderly, malnourished or muscular patients where creatinine-based eGFR is misleading. eGFR can be calculated from cystatin C alone or combined (most accurate).
Renal Ultrasound	Assesses kidney size, structure, obstruction, cysts and stones. Small kidneys (under about 3.5 inches, 9 cm) indicate chronic damage; large kidneys may indicate diabetic nephropathy or polycystic kidney disease. First-line imaging for CKD workup.
PTH, Vitamin D, Iron Panel, Ferritin	CKD causes secondary hyperparathyroidism (PTH rises early), vitamin D deficiency (kidneys activate 25-⁠OH-D to 1,25-⁠OH-D) and anemia of CKD (iron-restricted erythropoiesis). Monitor and correct each.
24-⁠Hour Urine Collection	Quantifies protein loss, creatinine clearance, sodium/potassium excretion. More accurate than spot urine for proteinuria assessment and for evaluating dietary sodium intake, useful when refining the CKD diet plan.

Chronic Kidney Disease

What Is Chronic Kidney Disease?

Stages of Chronic Kidney Disease

Stages 1 to 2 (Early)

Stage 3 (Moderate)

Stages 4 to 5 (Advanced)