Belly fat sounds easy to manage on paper by eating better, moving more and staying consistent. But after turning 30, many people notice a strange change. The same diet stops working, same workouts give fewer results. And belly fat starts building up quietly.
If this feels familiar, you are not alone. A Harvard-trained doctor says this change is not about laziness or lack of discipline. It is about what happens inside the body with age.
In a recent Instagram post, a California-based gastroenterologist trained at AIIMS, Harvard and Stanford (Dr Saurabh Sethi) explained why belly fat becomes harder to lose after 30. His message was clear. The problem starts internally, even if your lifestyle looks the same from the outside.
Why Belly Fat Increases After 30
According to Dr Sethi, the body begins to change in subtle but powerful ways after the age of 30. One major shift is muscle loss. Adults naturally lose around 3 to 8% of muscle mass every decade. Less muscle means the body burns fewer calories at rest.
Muscles also play a key role in handling sugar. Around 70 to 80% of glucose is processed by muscle tissue. When muscle mass drops, sugar stays in the bloodstream longer. The body then stores it as fat, often around the abdomen.
Another issue is declining insulin sensitivity. As people age, the body responds less efficiently to insulin. This means the same amount of carbohydrates now causes higher sugar spikes. These spikes push the body to store fat faster, especially around the waist.
Hormones also change after 30. Levels of growth hormone, testosterone and oestrogen slowly decline. At the same time, cortisol, the stress hormone, tends to rise. Dr Sethi explained that this mix strongly favours deep abdominal fat storage.
Over time, visceral fat builds up faster than surface fat. This deep fat surrounds internal organs and worsens inflammation and insulin resistance. The effect is stronger in people with fatty liver, prediabetes, diabetes, or high triglycerides.
Signs And Simple Ways To Reduce It
Many people notice clear warning signs as metabolism slows down. The waistline increases even when body weight stays stable. Energy drops sharply in the afternoon. Sugar cravings feel stronger. Carbs cause bloating. Fat gathers more in the upper abdomen.
Well, these changes can be managed with the right approach.
Dr Sethi suggested starting with protein. Adults should aim for around 1.2 to 1.6 grams of protein per kilogram of body weight each day. Protein helps preserve muscle and improves metabolic health.
Strength training is also crucial. Lifting weights at least three times a week helps rebuild muscle and boosts calorie burn. Daily walking improves insulin sensitivity and supports fat loss over time.
Sleep matters more than most people realise. Getting seven to eight hours of sleep each night helps balance hormones and control cravings.
Belly fat after 30 is not a personal failure, but a biological shift. Once you understand the reason, the solution becomes much clearer.
