Did you know that kidneys, like the heart and brain, are essential organs? March 13th, 2025 is World Kidney Day. Chronic kidney disease is a progressive condition affecting more than 10 per cent of people worldwide, or about 800 million individuals. This disease already threatens even more than 10 per cent, and the threat will only grow. Why? In short, because of climate change and the damage it can cause even to healthy kidneys.
To raise awareness about the importance of maintaining healthy kidneys, the international community commemorates World Kidney Day.
Kidney health and heat
Knowing whether you have healthy kidneys is often difficult, because many with kidney disease have no symptoms. The kidney is a vital organ, filtering waste products, toxins and chemicals from your blood, and getting rid of them in the urine. Keeping your kidneys healthy is crucial for your health. While some are simply more prone to developing kidney problems, we are all now more susceptible. Why is this?
Planetary temperatures have increased by almost 2°C, causing increased frequency of extreme heat, more marked near the equator, the geographical location of T&T and the Caribbean. The body’s response to high temperatures is sweating, which cools the body. Excessive sweating, however, leads to dehydration, reducing blood flow to the kidneys. Another kidney-threatening factor is the 80-90% humidity the region often experiences. These two marks of climate change mean that the Heat Index for T&T (calculated using both temperature and humidity) is commonly in the Red Zone. A high heat index results in profuse sweating, dehydration and can result in deterioration of kidney function. Some suffering these effects may be diagnosed with ARF (Acute Renal Failure), which can be reversed through rehydration and replacing electrolyte loss. Coconut water, rich in potassium, and other products are available for rehydration, though one should be cautious purchasing energy drinks which may contain caffeine or related products.
Who is vulnerable?
If untreated, ARF can progress to CRF, Chronic Renal Failure. You’re probably wondering who is most susceptible. Underlying health conditions like high blood pressure, diabetes, heart disease, obesity, sickle-cell disease, pre-existing renal disease, taking certain medications like diuretics (make you urinate more), some antihypertensives (blood pressure reducers) and non-steroidal anti-inflammatory drugs put you at risk. Because the body functions less well, such individuals are more prone to heat stress and heat stroke, which can lead to kidney injury.
One doctor recently shared that her elderly patients are often unable to care for themselves during very hot periods, because of fluid and electrolyte loss. Infants and young children who have a higher surface area-to-body mass ratio, also absorb heat from the environment more easily and are at higher risk.
Outdoor workers, including the military, police, agricultural workers, those in construction and athletes are at higher risk of kidney injury. Strenuous activity during the extremely hot/humid conditions described worsen outcomes. I have vivid memories of patients coming to me with discoloured urine and extremely painful muscles, because high heat generated by increased muscle activity damaged their muscle cells, releasing toxins into their bloodstream and damaging their kidneys. You may have just played mas and might be wondering how to find out if your kidneys are healthy!
How is kidney disease diagnosed?
Your doctor can do urine and blood tests confirming kidney health or problems. For those with underlying diseases or histories of renal disease, more detailed studies like ultrasounds, CT scans, MRIs or renal biopsies can be done to find out if you have CRF. People with CRF are put on restrictive diets that include low protein and electrolytes. Such individuals are candidates for renal dialysis and may benefit from a kidney transplant.
How to protect my kidneys?
What should you do if you want to maintain healthy kidney function? Don’t smoke, avoid consuming excessive alcohol and caffeine, maintain ideal body weight, exercise frequently and practice a healthy lifestyle. Treat underlying health conditions and remember: everything in moderation. Remember to drink enough, avoiding sugary high-energy drinks (even when they’re advertised to seem like the better choice!), opt for shady areas, minimise heat exposure, wear light clothing, hats, sunglasses, sunblock and choose cooler times for outdoor activities. Cold drinks, cool showers, air-conditioning or visiting a nearby mall if you do not own a unit, are great options. Keep an eye on media updates about heat!
Conclusion
Be aware of what keeps kidneys healthy, treat underlying diseases, and stay cool and hydrated. Remember, infants, children, the elderly, outdoor workers and people using certain medications are at higher risk. While avoiding heat is impossible in T&T and the wider Caribbean, using everything you just learned and listening to media updates about excessively hot days/days with high heat indices will go a long way towards protecting yourself – and one of your body’s most vital organs. Climate change is accelerating, so stay informed, and stay safe.
Dr Paula Henry, MB BS, MBA, MPH is a director of the EarthMedic and EarthNurse Foundation for Planetary Health
phenry@earthmedic.com
The foregoing was a weekly column by EarthMedic and EarthNurse NGO to equip readers to face the climate and health crisis.