Day 141 – 147 | Week’s FIRE Map

The kidneys are small but mighty organs quietly work behind the scenes, handling multiple jobs every day.

Your kidneys are two bean-shaped organs, each about the size of your fist, located just below your ribs towards your back. Every day, they filter roughly 200 litres of blood, removing waste, excess fluids, and toxins  –  which your body then gets rid of as urine. That’s an impressive workload!

But filtering is just part of their job. Your kidneys also balance essential minerals like sodium, potassium, calcium, and phosphate. They help control blood pressure through hormone signals and play a key role in making red blood cells and activating vitamin D, which keeps your bones strong.

When your kidneys are healthy, you hardly notice them. But once they start to struggle, it can affect everything  –  from your energy and blood pressure to how your body clears out toxins.

Insulin isn’t just about controlling blood sugar – it also helps your kidneys balance salt and protects their tiny filters, called glomeruli, which work like mini sieves to clean your blood.

When insulin resistance develops, your cells stop listening to insulin’s signals. This causes two problems: blood sugar levels rise, and your body produces more insulin to try to keep up. Over time, both high blood sugar and high insulin can damage your kidneys. Let’s take a closer look at how this happens:

• Glomerular Hyperfiltration: At first, your kidneys go into overdrive trying to clear the extra sugar, filtering blood faster than usual. This makes you urinate more frequently – a common early sign of diabetes called polyuria. Think of your kidneys like marathon runners who never get a break; eventually, they get worn out.
• Proteinuria: As high blood sugar damages the filters, proteins like albumin start to leak into your urine. This early warning sign, called proteinuria, is like your kidneys waving a little red flag that something’s wrong.
• Inflammation and Oxidative Stress: High sugar and insulin levels set off a chain reaction, causing ongoing low-level inflammation and forming harmful molecules. Imagine oxidative stress like tiny particles of “rust” slowly damaging your kidney tissue.
• High Blood Pressure: High insulin levels make your body hold on to more salt, which raises your blood volume and blood pressure. This extra pressure puts even more strain on your kidneys.
• Fat Buildup: Insulin resistance can also lead to fat collecting in and around your kidneys. This extra fat can cause scarring and make it even harder for your kidneys to do their job.
• Fluid Imbalance: When insulin isn’t working right, your kidneys may struggle to keep the right balance of salt and water. This can lead to swelling and keep your blood pressure high.

All these challenges add up, often leading to chronic kidney disease.

Chronic Kidney Disease, or CKD, means your kidneys are slowly losing their ability to filter waste and balance fluids in your body. This happens gradually over months or years. The early signs can be tricky to spot – maybe you’re feeling more tired than usual, noticing swelling in your ankles or feet, or peeing more – or less – than normal. Often, people don’t realise something’s wrong until kidney function has dropped a lot.

If CKD isn’t managed, it can raise your risk for serious issues like heart disease, anaemia, and bone problems. In the worst cases, it can progress to end-stage kidney failure, where you might need dialysis or a kidney transplant to survive.

CKD is a massive challenge worldwide, affecting about 850 million people and contributing to over 1.2 million deaths each year, along with countless cases of disability.

It also places a huge burden on healthcare systems, costing billions in treatment and management, which highlights the urgent need for prevention and early action.

Now, here’s something important: insulin resistance and diabetes are major drivers of CKD across the globe. But there’s good news too. While there’s no magic pill to cure CKD, you can slow it down by keeping things like blood sugar, blood pressure, and inflammation under control. Even better, insulin resistance – the root cause for many – can be reversed with lifestyle changes. By tackling insulin resistance head-on, you might prevent or even turn back the kidney damage.

Let’s talk about how different diabetes and other medications can affect your kidneys.

SGLT2 inhibitors (like empagliflozin and dapagliflozin – that’s Forxiga and Jardiance) are often prescribed to protect your kidneys and slow down kidney disease. However, if you’re aiming to reverse insulin resistance – the underlying cause of many kidney problems – by following a low-carb or ketogenic diet like FIRE, there’s an important warning. When you mix SGLT2 inhibitors with a very low-carb eating plan, your risk of developing a dangerous condition called ketoacidosis goes up – even if your blood sugar levels aren’t very high. This is a serious complication that can land you in the hospital, which is why we strongly recommend stopping SGLT2 inhibitors if you’re starting the FIRE diet. 

Metformin is generally safe in the early stages of chronic kidney disease, but if your kidney function drops, your doctor might need to lower your dose or switch your medication.

NSAIDs (like ibuprofen or naproxen) are popular painkillers, but they can be tough on your kidneys if taken often or in high amounts.

Certain antibiotics and contrast dyes (used in some medical scans) can also put extra strain on your kidneys, especially if you already have reduced kidney function.

Blood pressure medications are often kidney-friendly and even protective, but they need to be carefully chosen and monitored to make sure they’re helping and not causing any harm.

If you have questions about your medications, always keep the conversation open with your FIRE-friendly doctor. Never start or stop medicines on your own.

Chronic Kidney Disease (CKD) can feel overwhelming, but research shows that lifestyle changes – caring for your body, mind, relationships, and even sense of purpose – can make a real difference in slowing its progression and improving your wellbeing. We’ve dug deep into the scientific literature to bring you evidence-based strategies. Let’s dive into your kidney care toolkit!

Food as Medicine: Stick to the Green List

What you eat is a cornerstone of managing CKD. A low-carb, high-fat diet can stabilise blood sugar and ease the strain on your kidneys by reducing the workload of filtering excess glucose. Focus on healthy fats like avocados, nuts, olive oil, fatty fish or a Karoo chop, which have anti-inflammatory benefits that may help protect your kidneys. Research backs this up, showing low-carb diets improve glycaemic control and reduce CKD risk factors, especially for those with diabetes. Now, let’s debunk a myth: you don’t always need to drastically cut protein to save your kidneys. Recent studies suggest moderate protein intake – like on the FIRE diet, around 1.2 g/kg of body weight per day – is safe and beneficial in early to moderate CKD, supporting muscle mass and nutrition. Very high protein should be avoided in later stages, but restricting protein can sometimes actually do more harm than good! 

The power of fasting

Fasting (like doing a 23-hour fast on Mondays, Wednesdays, and Fridays) or occasional longer fasts (around 72 hours) may boost insulin sensitivity and lower inflammation, giving your kidneys a “rest” from constant processing. Fasting reduces blood pressure and oxidative stress – both tough on kidneys – and stimulates autophagy and stem cell production to assist with recovery. Stay well-hydrated with fluids and electrolytes while fasting. If unsure, always check with your FIRE-friendly doctor.

Restorative sleep

Good sleep – aim for 7–9 hours in a cool, dark, quiet space – is crucial for your body to repair. Poor sleep messes with blood sugar, blood pressure, and inflammation, all stressing kidneys. Research links sleep issues like apnoea to faster CKD progression, so prioritising quality rest with a consistent bedtime can help.

Stress management and social support

Chronic stress spikes cortisol, blood sugar, and blood pressure, hitting kidneys hard. Practices like prayer, mindfulness, meditation, journaling, nature walks, or connecting with loved ones ease this burden. Studies show reducing stress and having a supportive community (even virtual) lowers inflammation and improves CKD outcomes while helping stick to healthy habits. Nurture your Uppers!

Hormesis: Building resilience through exercise

Small, controlled stressors – known as hormesis – like moderate exercise or 90 seconds under a cold shower, help your body adapt and grow stronger. Exercise slows CKD progression, boosts quality of life, and supports heart health by improving circulation and reducing inflammation. While it may not directly improve kidney filtration rates, physical activity reduces frailty and manages risk factors like blood pressure and weight. Even light activities like brisk walking or swimming, tailored to ability, make a difference. Do your FIRE Fit exercises every day!

Conscious breathing and mindfulness

Even your simple FIRE Fit breathing exercises are important – they can lower blood pressure and calm stress, indirectly supporting kidneys. Prayer and mindfulness meditation cuts stress-related damage. Though direct CKD studies on breathing are limited, its effect on hypertension – a major CKD driver – makes it valuable.

Research shows lifestyle changes – diet, fasting, sleep, movement, stress management, mindfulness, and having fun with others – can slow CKD progression, boost quality of life, and manage risk factors, even improve kidney function.

Supplements can give your kidneys an extra layer of support, but they work best alongside a healthy lifestyle. They’re not a magic fix. It’s always a good idea to discuss any new supplements with your FIRE-friendly healthcare provider to make sure they’re right for you. Below is a list of vitamins, antioxidants, and adaptogens that can be tailored to your personal needs with your doctor’s guidance.

Vitamins

• Vitamin D
  Vitamin D helps your body balance calcium and phosphorus, which is important for strong bones and a healthy immune system. Getting enough Vitamin D may also reduce inflammation and gently support your kidneys.
  Dosage: Usually 8,000 to 16,000 IU daily, aiming for blood levels around 80 ng/ml.

• Delta Tocotrienol (Vitamin E form)
  This form of vitamin E acts as an antioxidant and may help lower inflammation, especially in early stages of kidney disease.
  Dosage: 125 mg a day, best taken with a meal that has some healthy fat.

• Magnesium
  Magnesium supports your blood vessels, nerves, and more than 350 cellular reactions.
  Dosage: 500–1,000 mg magnesium oxide per day, only if your doctor advises.

Antioxidants

• Omega-3 Fatty Acids
  Found in fish oil, omega-3s help calm inflammation – making them great for both heart and kidney health.
  Dosage: 2,000 mg daily.

• Coenzyme Q10 (CoQ10)
  This antioxidant protects kidney cells and boosts your body’s energy production. Some studies show it may help slow kidney issues.
  Dosage: 200–600 mg per day.

• Alpha-Lipoic Acid
  Another powerful antioxidant, especially helpful for people with diabetes. It helps your body handle glucose and eases stress on your kidneys.
  Dosage: 200–600 mg, up to three times daily.

• N-Acetylcysteine (NAC)
  NAC boosts your body’s own antioxidant powers. It may protect your kidneys from injury.
  Dosage: 600–1,200 mg daily.

• Curcumin
  The active part of turmeric, curcumin is known for fighting inflammation and oxidative stress, possibly slowing down kidney decline.
  Dosage: 500–1,000 mg daily, ideally with a pinch of black pepper for better absorption.

• Modified Citrus Pectin (MCP)
  MCP may protect your kidneys by reducing scarring and inflammation. It works by blocking a protein (Galectin-3) linked to kidney damage. The main downside is the cost.
  Dosage: 5–15 grams daily in powder form.

• Resveratrol
  Resveratrol, found in grapes and red wine, is a popular antioxidant. It may help your kidneys by reducing stress and inflammation and protecting the kidney cells. In Southern Africa, people also use Eucalyptus Bark Extract and Papaya Seed Extract (2 capsules daily of each). These locally available antioxidants work in similar ways to reduce cell damage and inflammation.

Adaptogens

Herbs like rhodiola, ginseng, and ashwagandha help your body handle stress, lower inflammation, reduce oxidative damage, and boost your energy – sometimes easing fatigue that comes with chronic kidney issues. In Southern Africa, Sutherlandia (also known as Cancer Bush) (1000 mg daily) is a favourite, affordable adaptogen for kidney support.

Prebiotics and Probiotics

Keeping your gut healthy can also benefit your kidneys! There’s a close relationship between your gut and kidneys – sometimes called the gut-kidney axis. When your gut bacteria are out of balance (a condition called dysbiosis), it can actually put extra stress on your kidneys and worsen inflammation. Taking prebiotics and probiotics may help restore balance to your gut bacteria, lower toxin build-up, and calm inflammation throughout your body. Aim for multi-strain probiotics in the range of 10–50 billion CFUs daily, along with about 10 grams of inulin (a type of prebiotic fibre) each day.

Here’s the encouraging news: your kidneys have the amazing ability to heal, especially if issues are caught early and you give them the right support. The FIRE lifestyle – healthy eating, fasting, good sleep, stress management, and mindful living – really does add up over time. When you combine these positive habits with the right vitamins, antioxidants, and gut support tailored to your needs, you’re putting yourself on the road to recovery.

Remember, you’re not alone in this journey. Celebrate every bit of progress, no matter how small, and treat yourself with compassion and patience along the way.

Your kidneys work quietly every day to keep you healthy – so show them the same care, kindness, and commitment. Healing is possible, and you’re already on your way.