The cricketer turned politician Navjot Singh Sidhu claimed in a January 29 Facebook post that he had lost 33 kgs within five months through lifestyle changes and dietary modifications. 

 “Before and after … have lost 33 kilograms in less than 5 months since August last year … it was all about willpower, discipline, process and a strict diet facilitated by pranayama (breath control ) weight training and walking ….. impossible is nothing people … ‘ pehla sukh nirogi kaya,” the post read. 

This works out to a weight loss of 6.6kg or about 13 pounds a month. While this may be achievable, is it biologically sustainable? 

What’s the fact?

Losing weight through lifestyle and dietary changes is good for health, but experts and studies warn that shedding pounds too quickly can lead to muscle loss.

“Slow loss is good loss: Start losing weight early, focusing on 1 to 2 pounds per week. This will assume that the weight which you lose is mostly fat. Weight loss of more than 2-3 pounds will result in things you don’t want like muscle loss,” says a report in Children’s Hospital Colorado.

The principle of weight gain is simple: energy intake exceeds energy expenditure. So, weight loss follows when energy expenditure is more than energy intake. 

Any strategy geared to lose weight has to be customised to suit an individual’s body type, note these recommendations by the National Heart, Lung, and Blood Institute, an official health website of the United States government. 

“The initial goal of weight-loss therapy should be to reduce body weight by about 10 percent from baseline. With success, and if warranted, further weight loss can be attempted,” the website suggests. “Weight loss should be about 1 to 2 pounds per week for a period of 6 months, with the subsequent strategy based on the amount of weight lost.”

A report in the Centre for Disease Control (CDC) too recommends a weight loss of  1-2 pounds per week and advises against rushing the process. 

“People who lose weight at a gradual, steady pace—about 1 to 2 pounds a week—are more likely to keep the weight off than people who lose weight quicker,” the report points out.

Expert concerns about rapid weight loss

Priya Agarwal, Clinical Dietitian at TGH Onco, Life Hospital in Pune said that losing 33 kg in just 5 months, especially at the age of 61, has potential health risks. 

“When weight loss occurs too quickly, the body may start to break down muscle tissue, which can slow down metabolism and make it harder to maintain weight loss,” she told First Check.

Rapid weight loss, according to her, can also lead to inadequate nutrient intake, causing weight loss and related health issues, including negative impact on hormones.

“Rapid weight loss can affect hormone levels, including a decrease in Leptin, which regulates energy balance and metabolism,” she said. “Severe calorie restriction and rapid weight loss can disrupt the electrolyte levels, leading to muscle cramps, fatigue and other complications.”

She continued: “Severe calorie restriction and rapid weight loss can weaken the immune system, making it harder for the body to fight off infections.”

Another potential risk could be the risk of “developing gallstones,” small, hard deposits that can form in the gallbladder, Agarwal warned.

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