Visceral fat is located deep in the core abdominal area, surrounding and protecting the vital organs. Too much visceral fat creates can lead to inflammation and high blood pressure, which increases the risk of serious health problems. This is also know as central obesity.
Another problem with viscera fat is its impact on adiponectin or 'fat hormone'. Adiponectin's function is to regulate your body fat. Visceral fat inhibits adiponectin. As a result your body produces more fat than actually need. A high level of visceral fat also influences your insulin sensitivity. Which means that it can lead to type 2 diabetes later in life.
Even if an adult’s weight and body fat remains constant, the distribution of fat naturally changes with age and is more likely to shift to the abdominal area as they get older. Ensuring a healthy level of visceral fat directly reduces the risk of certain diseases such as heart disease and high blood pressure and may delay the onset of type 2 diabetes.
Here you can find more information about visceral fat.
To understand how TANITA measures visceral fat, please read: