How Exposure to Hot and Cold Affects Kidney Health

November 3rd, 2025 by Dr Josh M Randall

Edema, changes in urination, constant fatigue and weakness, shortness of breath, nausea, and high blood pressure are all symptoms of impaired kidney function. Diabetic nephropathy, infection, kidney stones, cancer, urolithiasis, cystitis, and more can develop. How to protect your health? First, you need to understand the cause of the disease. The latest research is surprising. It turns out that the climate has a significant impact on kidney function. Extreme temperatures sometimes increase the risk of CKD. Let’s learn how to prevent this and maintain your health for years.

Research: Heat and Cold Effects on Kidney Health

In 2019, 1.43 million people died from kidney disease. Kidney disease mortality is associated with ambient temperature, but most studies focus on summer heat. Researchers set out to quantify the short-term relationship between ambient temperature and kidney disease mortality in Japan and assess how this relationship changed from 1979 to 2019. Experts analyzed 997,590 kidney disease deaths in 47 prefectures. Heat increased the risk primarily in previous decades, but not recently. An estimated 11.21% of kidney failure deaths were attributable to cold.

Cold exposure remains a stable and significant risk factor for kidney failure mortality in Japan. Protecting patients with impaired kidney function during cold weather should be a priority.

Why is cold important for the kidneys? Possible mechanisms include dehydration during the cold season, which causes hemodynamic stress on renal perfusion; seasonal electrolyte imbalances; and cold-induced vasoconstriction and increased blood pressure. Older women are more vulnerable to colds. It is likely related to thermoregulatory factors, hormonal balance, and comorbidities.

The following study aimed to determine how exposure to high and low temperatures affects kidney function in people with diabetes, hypertension, and chronic kidney disease. The researchers used a retrospective cohort from St. Mary’s Hospital in Seoul’s clinical data repository, which has contained detailed patient records since 1997. Heat exposure was measured using a heat index. It combines temperature and humidity to reflect perceived temperature.

The analysis revealed a significant linear decline in kidney function as the heat index increased to approximately 25°C. This study provides compelling scientific evidence that high temperatures negatively impact kidney function in patients with chronic diseases. These findings are critical for public health initiatives, allowing for more accurate identification of high-risk individuals and the development of prevention strategies for heat-related kidney disease.

Temperatures above 25°C significantly correlate with decreased kidney function in patients with chronic diseases (diabetes, hypertension, and chronic kidney disease). The results provide a scientific basis for developing public health policies to prevent heat-related illnesses. They can help identify individuals at high risk of developing or worsening kidney disease and raise public awareness of the health risks associated with climate change.

High Temperature and Kidney Disease

Studies show that hot weather increases hospitalizations related to kidney disease by 30%. For people with chronic kidney disease, summer heat and sun pose significant health risks. To help you manage these risks, we’ve compiled important tips from leading experts.

Why Is Heat a Threat to Your Kidneys?

In hot weather, the body loses fluid through sweat. Healthy kidneys compensate by retaining water. This results in more concentrated urine. Thirst prompts you to drink more. However, if you have chronic kidney disease, are on dialysis, or have had a kidney transplant, your kidneys will not function as well as usual. It makes it more challenging to maintain this delicate fluid balance.

Practical Recommendations for All Kidney Disease Patients in Hot Weather

Listen to your thirst. Don’t wait until you feel thirsty to drink water. Remember that sugary drinks may be less effective at quenching thirst. You shouldn’t rely on alcohol for hydration. Salt intake is usually limited. A slight increase during extreme heat can help the body retain essential fluids. However, always consult your doctor first.

Additional recommendations:

• Avoid sun exposure during peak hours.
• Rest in the shade and wear a wide-brimmed hat.
• Reduce physical activity in hot temperatures.
• Be aware of signs of dehydration. Watch for dark yellow urine, dizziness, fatigue, and dry mouth.
• Check your weight and blood pressure regularly.
• Use sunscreen with SPF 50 year-round, not just in the summer.
• Wear protective clothing and a hat in the summer.
• Avoid sunbathing and never use tanning beds.

Manage your kidney health and enjoy a safe summer. Always consult your doctor for personalized advice.

Cold Exposure and Kidney Disorders

Winter can be challenging for anyone. But for people with kidney disease, dialysis patients, or organ transplant recipients, cold weather can create additional health challenges. How can you protect yourself and stay healthy in low temperatures? Read on to learn more.

How Does Cold Weather Affect Your Kidneys?

In cold weather, blood vessels constrict to conserve body heat, which increases blood pressure. This strains the heart and kidneys, reducing blood flow and the ability to function properly. If cold weather lasts more than three days, the risk of heart attack and stroke in people over 60 can double.

Cold air can weaken the immune system, making you more susceptible to colds, flu, and other respiratory infections. In people with kidney disease, these infections can quickly progress to serious illness. Cold stress, dehydration, and high blood pressure can contribute to kidney strain in winter. Many people with chronic kidney disease suffer from anemia due to low iron levels, which can increase cold sensation.

Protection from the Cold

1. CKD patients are at increased risk of influenza, pneumonia, and COVID-19 complications. Discuss your annual flu shot, pneumococcal vaccine, and COVID-19 booster with your healthcare provider.
2. If you are over 50 or taking immunosuppressants, ask about the shingles vaccine.
3. Keep your home warm. Heat the room you spend most of your time in to at least 18°C (64°F).
4. Wear several layers of thin wool, cotton, or fleece clothing.
5. Dehydration can also occur in winter, increasing the risk of kidney damage.
6. Women should drink eight glasses (200 ml each) of fluid daily. Men should drink 10 glasses of water.
7. If you are restricting your fluid intake, follow the recommendations of a nephrologist.
8. Rehydrate immediately after vomiting or diarrhea.
9. Close doors and protect against drafts to retain heat.

Cold weather doesn’t necessarily mean poor health. Good preparation for the cold weather will help reduce health risks in winter and protect your kidneys throughout the season.

Conclusion

Now you know that temperature changes and kidney function are closely related. Be sure to take care of yourself in any weather. Be especially careful with your health if you have kidney problems. And of course, consult a doctor promptly. The Orange County Urology Associates specialists are ready to provide you with professional, patient-centered urological care. Our modern urology clinic serves all Orange County, Anaheim, Los Angeles, and San Diego patients worldwide. OCUA’s 11 experienced urologists use the latest technology and techniques and advanced diagnostic tests to help patients regain their health. Make an appointment with us with any urological concerns, and we will help!