Berten's ligament is a classic fatography error, typical of young children, which manifests itself in uneven fat deposits like a “belt” around the waist. One of the most common forms of disproportionate fat deposition is at the age of 4-6 years (in girls), when the belly accumulates in just a couple of weeks, and the formation of secondary sexual characteristics, such as swelling of the mammary glands, has not yet been completed. Another reason for the occurrence of bertin's ligament is deficiencies in protein nutrition. In boys, this error is called an “O-shaped figure.” The Bertin ligament should not be confused with a constitutional feature. This is diastasis or separation of the rectus abdominis muscles. This ordinary “detail” appears in humans without any influence of nutrition. Its appearance is due to the fact that over the years, the cervical vertebrae, ribs, and sternum gradually shift downward and forward in relation to the pelvis, and therefore the normal distance between them is disrupted and there is no threat of skin rupture along the midline of the abdomen from their excessive displacement. And the reason for the shift is growing up. In 3-7 year old children, the left and right parts of the abs are normally close together tightly - this is another nuance of the Bertin ligament in children.