Kidney Cleanse: Do Your Kidneys Really Need One?
Your kidneys filter your blood around the clock. Here is why a juice, fast or herbal kidney cleanse is not needed, how some cleanses can put extra strain on the kidneys, and the simple habits that actually protect them.
Kidney cleanse programs are easy to find. Some ask you to drink only juice for a few days. Others combine fasting with large amounts of water, green smoothies, vinegar, vitamin C or capsules of herbs, all with the promise of flushing your kidneys clean.
It sounds sensible. After all, your kidneys clean your blood, so why not give them a hand? The trouble is that healthy kidneys do not need a cleanse, and some of the methods used can make life harder for them, not easier.
Your kidneys already clean themselves
Your two kidneys clean toxins and waste out of your blood, which then leave the body as urine. Cleveland Clinic explains that they filter about 190 liters (200 quarts) of fluid a day, but reabsorb most of it, so most people pass about 1.9 liters (2 quarts) of urine daily.
They also balance fluids and minerals such as sodium and potassium, and they help control blood pressure. This is ongoing, automatic work. There is no build-up of sludge waiting for a special drink to wash it away.
What the evidence says
In a Cleveland Clinic interview, kidney specialist Dr. Juan Calle said there is really no medical evidence to support kidney cleanses, and that some cleanses may actually be harmful to the kidneys. He also said there is no strong evidence to recommend fasting for kidney health.
This fits the wider picture. NCCIH, part of the US National Institutes of Health, reviewed detox and cleanse programs and found only a small number of human studies, mostly of low quality, with no studies of long-term effects. The US Food and Drug Administration and Federal Trade Commission have acted against some detox sellers over hidden ingredients and false claims about treating disease.
Where kidney cleanses can backfire
Overloading on certain foods. Dr. Calle described people who fast for long periods and then overdo foods such as spinach, kale, beets and rhubarb, or high doses of vitamin C, in ways that can affect the kidneys. NCCIH notes that some cleanse juices, such as those made from leafy greens and beets, are high in oxalate, and that people prone to kidney stones should limit high-oxalate foods.
Flooding the body with fluid. NCCIH warns that drinking large amounts of water or herbal tea while eating very little for days could cause dangerous imbalances in electrolytes, the minerals your kidneys work to keep steady.
Pills of unknown content. Dr. Calle pointed out that supplements are not well monitored. A capsule labeled as a kidney cleanse may contain herbs or amounts you would not expect.
Unpasteurized juice. Juices that have not been treated to kill germs can make people ill, and NCCIH says this can be serious for children, older adults and people with weak immune systems.
What actually helps your kidneys, step by step
Step 1: Drink water through the day so you stay hydrated. You do not need to force huge amounts.
Step 2: Limit salt, stay physically active and keep to a healthy weight. Eat plenty of fruit and vegetables, the right amount of protein, and fewer ultra-processed foods.
Step 3: Keep blood pressure and, if you have diabetes, blood sugar under control. These matter more than any cleanse.
Step 4: Use anti-inflammatory pain relievers known as NSAIDs, such as ibuprofen, sparingly. Cleveland Clinic warns that frequent use can damage the kidneys.
Step 5: Do not smoke, and ask your doctor about regular blood and urine tests. These show how well your kidneys are working; a cleanse cannot.
Questions people ask
Can cranberry juice or apple cider vinegar cleanse my kidneys?
None of the medical sources we checked supports any drink as a kidney cleanse. Your kidneys do the cleaning themselves; what helps is staying hydrated and looking after your blood pressure and blood sugar.
Is it good to drink as much water as possible?
No. Drinking enough to stay hydrated helps, but very large amounts, especially while eating little, can upset your electrolyte balance.
How do I find out if my kidneys are healthy?
Ask your doctor. A simple urine test and blood test show how well your kidneys are filtering. A cleanse cannot tell you this.
Sources
- Is a Kidney Detox Safe? with Juan Calle, MD — Cleveland Clinic
- Kidneys: Location, Anatomy, Function and Health — Cleveland Clinic
- "Detoxes" and "Cleanses": What You Need To Know — NCCIH
This article is for general information only and is not medical advice. Herbs can interact with medicines and health conditions. Talk to a doctor or pharmacist before trying a herbal remedy, especially if you are pregnant, breastfeeding, giving it to a child, or taking any medication.
