For anyone trying to lose weight, one of the earliest pieces of advice is predictable: cut down sugar. While this may sound like a simple dietary suggestion, medical experts say the science behind it is far more compelling. According to University of Utah Health, excess sugar overwhelms the liver, forcing the body to convert it immediately into fat. Now, a viral explanation by robotic GI surgeon and obesity specialist Dr Anshuman Kaushal has helped many understand why sugar keeps pushing weight upwards despite exercise.

Why the body keeps turning sugar into fat

In a widely shared Instagram video posted on December 2, Dr Kaushal says, “Sugar is not sweet at all. Sugar is strategic. It hijacks insulin, fills fat cells, and leaves you blaming genetics.”
He compares the body to a banking system with three accounts:

  • Current account – your blood glucose level, which must stay between 70–100 mg/dL.
  • Savings account – liver and muscle glycogen.
  • Fat locker – long-term storage for excess sugar.

Tea, biscuits, aerated drinks, sweets and desserts, he says, constantly “top up” the current account, overwhelming the body’s manager — insulin. Fearing a metabolic crash, insulin immediately begins storing excess glucose in the glycogen “savings account”. But this too has a limit. Once full, all extra sugar is rerouted to the fat locker, leading to rapid fat gain.

How excess sugar affects health

High sugar intake also elevates HbA1c, the blood marker indicating average glucose over 2–3 months. With repeated spikes, insulin remains chronically high, blocking fat-burning pathways.
Dr Kaushal adds, “Ever wonder why gyms are full but waistlines are fuller? Because every sugar top-up goes straight to the fat locker.”

He emphasises that weight gain is often less about “slow metabolism” and more about “constantly high insulin”.

What you can do

Dr Kaushal’s advice is straightforward:

  • Reduce sugar to prevent frequent insulin spikes.
  • Keep the “current” and “savings” accounts steady, so the body does not activate the fat locker.
  • Understand that drinks like cold coffee or desserts like gulab jamun are treated as pure fat once in excess.

“Reduce sugar, reduce insulin spikes, unlock fat-burning mode,” he concludes.