Brown fat

Looks like

Tissue of smaller cells with many small fat droplets and many mitochondria, which give it its colour; in adults mainly in the neck and above the collarbones.

What it does

Burns fat to make heat, keeping newborns and cold-exposed adults warm.

Keeping it well

Cold exposure activates it. It is abundant in babies, so they rely on it to stay warm and need to be kept warm.

Related conditions

• Obesity