Can belly fat shrink your brain? Top neurologist explains the hidden link between visceral fat, memory loss, and dementia risk

Many people focus on improving their health to prevent diabetes, heart disease, or obesity, but an often-overlooked factor could quietly be influencing another vital organ. Scientists are increasingly discovering that what happens inside the body can have long-term consequences beyond metabolism, potentially affecting how people think, learn, and remember as they age. Understanding these hidden risks has become an important part of healthy ageing. Highlighting the growing evidence, Apollo doctor, a top neurologist Dr Sudhir Kumar recently shared on his X handle how excess visceral fat may significantly increase the risk of cognitive decline and dementia.

According to Dr Kumar, not all body fat behaves in the same way. While fat stored just beneath the skin is relatively less harmful, visceral fat—the deep abdominal fat surrounding internal organs—is metabolically active and far more dangerous. Growing research suggests that higher levels of visceral adipose tissue are associated with poorer brain health, even after accounting for a person's age and overall body weight.

Why visceral fat is more harmful than ordinary body fat

Visceral fat differs from the fat that sits under the skin because it actively releases inflammatory chemicals and hormones that can disrupt several processes throughout the body. Unlike subcutaneous fat, this deep abdominal fat surrounds vital organs and is strongly linked to chronic diseases. Studies have found that people with greater amounts of visceral fat are more likely to experience cognitive decline, develop dementia, and show reductions in overall brain volume. Researchers have also observed a smaller hippocampus—the region responsible for learning and memory—in individuals with higher visceral fat levels.

How excess abdominal fat can affect the brain

The relationship between visceral fat and brain health is driven by multiple biological changes rather than a single factor. Excess abdominal fat promotes chronic low-grade inflammation, which can gradually damage brain cells over time. It also contributes to insulin resistance, high blood pressure, unhealthy cholesterol levels, and damage to the body's smallest blood vessels, all of which can reduce healthy blood flow to the brain. Hormonal changes linked to visceral fat may further interfere with normal brain function. Together, these processes can slowly impair memory, thinking, and overall cognitive performance.

Brain function may decline long before dementia appears

Research suggests that the impact of visceral fat on the brain often begins years before dementia becomes noticeable. People carrying higher levels of abdominal fat may experience reduced executive function, making it harder to plan, organise, and make decisions. They may also process information more slowly, struggle with attention, and perform worse on memory-related tasks. These subtle cognitive changes may develop gradually, highlighting the importance of addressing visceral fat early rather than waiting for symptoms of memory loss to appear.

The most effective ways to reduce visceral fat

Dr Kumar emphasises that there is no scientifically proven "fat-burning" supplement capable of specifically targeting visceral fat. Instead, the strongest evidence supports sustainable lifestyle changes. Regular aerobic exercise combined with strength training at least twice a week can significantly reduce abdominal fat while improving overall metabolic health. Following a Mediterranean-style diet rich in vegetables, fruits, whole grains, healthy fats, lean protein, and fibre also supports healthy weight management. Sleeping for seven to nine hours each night and maintaining a healthy body weight further contribute to lowering visceral fat and protecting long-term brain health.

Don't judge health by the weighing scale alone

Dr Kumar also advises looking beyond body weight when assessing health risks. Waist circumference and waist-to-height ratio often provide a clearer picture of visceral fat than the weighing scale alone, with a waist-to-height ratio below 0.5 considered a useful target for most adults. For individuals living with diabetes, prediabetes, hypertension, or fatty liver disease, reducing visceral fat becomes even more important, not only for protecting the heart but also for preserving brain health and lowering the risk of future cognitive decline.