A one-size-fits-all approach to IF is inappropriate, particularly for those with renal and cardiac vulnerability. Photograph used for representational purposes only
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The trend of intermittent fasting is growing in the community, and it has gained popularity among those trying to improve their general health or control their weight. There has also been interest in the possible benefits of intermittent fasting (IF) in promoting health and combating chronic diseases. But it is important to understand how IF works in order to avoid health issues and ensure optimal outcomes.

The kidney is essential to maintain the body’s equilibrium. Maintaining the body’s balance depends on the kidneys’ ability to filter waste, regulate blood pressure, and control fluid and mineral levels. Any substantial change in eating habits can affect how they operate.

Who can and cannot practice IF

When done correctly, intermittent fasting is generally safe for those with healthy kidneys. It might even be beneficial, by improving blood sugar regulation and reducing inflammation, both of which, over time, can support kidney function. A family history of kidney problems, diabetes, high blood pressure, or pre-existing renal disease, on the other hand, raises concerns. Long-term meal skipping or inadequate hydration can lead to dehydration, which strains the kidneys. Certain forms of fasting that restrict fluid intake, particularly when done for extended periods or in heated environments, could raise the risk of kidney stones or perhaps serious kidney damage.

These days, different salt compositions are increasingly consumed with different kinds of food, which may cause harm rather than benefit a patient with kidney and cardiac problems in particular. Fluid intake in excess can also be a problem with already weak kidneys. While intermittent fasting holds promise as a metabolic intervention, its effects on kidney health depend heavily on individual patient profiles. A one-size-fits-all approach is inappropriate, particularly for those with renal and cardiac vulnerability. It is important to counsel patients on both the potential benefits and risks of IF, offering personalised strategies for safe implementation.

Also Read:Intermittent fasting inhibits hair regeneration in mice: study

If in doubt, ask a doctor

Fasting may sometimes create imbalances and may also damage kidney function if done without a doctor’s instructions. Also, deterioration of kidney function can lead to the need for dialysis or a kidney transplant. Dialysis, which occurs multiple times each week, is when a machine is used to filter the body’s waste and fluids. A kidney transplant is where the damaged kidney is replaced with a functioning kidney from a donor. Typically, when patients are on dialysis, it is best not to fast because it may impair their ability to take in their fluids and electrolytes.

Intermittent fasting can be beneficial in certain circumstances, but how it affects kidney function depends on the person’s general health. Before beginning any fasting regimen, anyone with known renal problems or risk factors should speak with a doctor. Simple dietary adjustments can have a significant impact on important organs, and thus, it is always safer to proceed under supervision.

(Dr. Saurabh Khiste is a consultant nephrologist at Manipal Hospital, Baner, Pune. Email: saurabh.khiste@manipalhospitals.com)

A: The increase in core temperature observed during illness is commonly called fever and occurs in response to infection by a pathogen or certain types of physical injury. When a person becomes infected with bacteria, the white blood cells of the immune system recognise the incoming pathogen as foreign and initiate the first stages of the immune response: the acute phase.

In this reaction, white blood cells called monocytes release a variety of proteins called cytokines. They are central to the immune response. In particular, there is a predominance of two types of cytokine called interleukin-1 and tumour necrosis factor-alpha. These cytokines cause an increase in body temperature.

It is not clear how but it is known that they also cause the production of other chemicals in the brain. The main group of chemicals here are the postaglandins. They react very strongly with the hypothalamus area of the brain, which then sends a signal to the body to increase the temperature.

The mechanisms that the brain employs to effect this are not certain but are known to include increasing the metabolic rate and shivering. These two processes burn metabolic fuel faster than normal, and body heat is given off.

Experimental work shows that elevated temperatures can enhance certain aspects of the immune response. The growth rates of various types of bacteria are slowed at temperatures above normal body temperature.

– Nigel Eastmond, University of Liverpool

The lack of widespread, equitable preparedness and awareness increases the risk, especially for daily wage workers, outdoor laborers, and communities with limited access to healthcare or shelter |Image used for representational purpose only
| Photo Credit: Getty Images

At least 35,000 lives were lost in India due to exposure to extreme hot and cold temperatures between 2001 and 2019, a new study has found.

Climate extremes and health impacts

In 2015 alone, it estimated 1,907 deaths due to a heatstroke and 1,147 because of cold exposure. Data for analysis was taken from the India Meteorological Department and National Crime Records Bureau, among other datasets. Findings, published in the journal Temperature, show an upward-moving, increasing trend in deaths due to a heatstroke and exposure to cold temperatures.

Lead author Pradeep Guin from O P Jindal Global University, Haryana, said that deaths due to exposure to extreme temperatures are avoidable and that measures to mitigate health impacts need to be put in place.

“With an intense heatwave forecast to hit most of the country this summer and extreme weather events becoming more frequent around the globe as the world warms, there is no time to be lost in raising awareness about the dangers of extreme temperatures and putting in place measures to reduce their impact,” Guin said.

He added, “Support systems exist, but more needs to be done.” Deaths due to extreme temperatures were found to be more common among men of working age.

During the study period of 2001-2019, deaths due to extreme heat were three to five times higher among men, while those due to extreme cold were four to seven times higher, compared to women, the researchers said.

Extreme weather risks and response plans

State-wise, Andhra Pradesh, Uttar Pradesh, and Punjab were found to record the most deaths due to a heatstroke, whereas the most deaths due to exposure to extreme cold came from Uttar Pradesh, Punjab, and Bihar.

The authors wrote, “Between 2001 and 2019, India reported 19,693 and 15,197 deaths due to heatstroke and cold exposure, respectively.” Guin said, “Deaths due to heatstroke is more significant, compared to deaths due to cold exposure, albeit recording an upward trend.” Co-author Nandita Bhan from the school of public health and human development at O P Jindal Global University, said the results highlight the urgent need of heat and cold action plans for vulnerable states.

“Several states in India are developing heat action plans that can provide relief through innovative built environment initiatives, and these need study as well as scale-up, including expanding cold action plans across more vulnerable states,” Bhan said.

Previous studies have largely looked at health impacts of extreme temperatures in developed countries and one-off events, such as a heatwave, rather than looking at low- and middle-income countries, the researchers said.

They added that with India experiencing temperature extremes each year, it is important to know places most at risk, which can help in designing measures to keep population safe.

Rapid weather fluctuations

A recently published study in the journal Nature Communications showed that ‘rapid flips’ in temperatures — a switch between hot and cold extremes in a relatively short time — have increased in 60 per cent of the world’s areas over the past 60 years.

It said that because of the limited time available to adapt to temperature changes, these flips could magnify the negative effects of hot and cold extremes on societies and nature, impacting humans and animals, infrastructure and agriculture.