How much does the human skeleton weigh? What causes the differences in skeleton weight? How does the weight of the skeleton change during a human’s life? This article will go into the details of these questions to help you understand the human body better.
The human skeleton has had millions of years to evolve since it is the cornerstone of current human physiology.
All the changes in size, shape, and weight were evolutionarily advantageous, so what was the final product? Let’s go into the details and find out;
How Much Does The Human Skeleton Weigh?
The skeleton makes up about 15%of a person’s total body weight, so a person who weighs 70 kg will have a 10.5 kg average skeleton. The skeleton density and weight change based on genes, gender, activities, and other factors, but it peaks between 25 and 30.
Children have more bones than adults but are smaller and less dense; thus, lighter and older people also have lighter bones than people in their prime.
What Factors Affect The Weight Of A Human Skeleton?
There are minor differences in human skeleton weights at the same age and gender which implies that there are factors that contribute to the exact value.
So what aspects of the human skeleton determine how heavy their bones are? Let’s take a close look and find out;
1. Age and Sex
Age affects the weight of the skeleton by affecting size and processes. Younger people generally are smaller and developing, so they have smaller skeletons. As they grow, factors like bone growth and bone density will change the weight of their skeleton.
Adolescents’ bones get denser and heavier as they hit puberty and experience rapid growth. The weight will reach its maximum between 25 and 30 and get less dense as a person ages.
Averagely, males have heavier skeletons and more bone density than females due to genetic and hormonal factors. Hormones like estrogen and testosterone play a role in bone growth and development, and their variations in men and women bring the difference.
2. Body Size and Composition
People with larger or heavier body sizes often have heavier skeletons. The human body adapts to its environment, changing bone density over time to help support the body’s weight and structure. A larger body needs more bone mass, so the skeleton adapts.
The ratio of lean mass to body fat also affects the weight of your skeleton. Lean mass refers to bones, muscles, organs, etc.
People with higher muscle mass tend to have more skeletal weight since there is higher demand on the bones from the muscles.
Heavy lifting activities and exercises can stimulate bone growth and increase density. This means that physically active people generally have denser and heavier bones than those that don’t.
3. Genetics and Nutrition
Your parent’s genes play a role in determining bone structure, density, and size. Some individuals have genetically predetermined characteristics that will make their skeletons lighter or heavier regardless of their activity levels or size.
Proper development and maintenance of bones depends on nutrients such as calcium, vitamin D, and proteins. The adequate amount of these nutrients will lead to stronger bones with higher bone density, making for a heavier skeleton.
4. Medical Conditions, Injury, and Trauma
Certain medical conditions, such as osteoporosis or osteogenesis imperfecta, can lead to bone density and structure alterations. This can change the skeleton’s weight, and sometimes, the treatments for such conditions bear the same effects.
Surgeries, fractures, other types of injuries, and skeletal trauma can change the bone structure and weight.
Skeleton Weight Changes During Humans Lifetime
The human skeleton is constantly changing and adapting to give you the best service based on what you do. So how does the skeleton change from childhood as you grow up and age? Let us look at the complete life cycle and find out;
Infancy and Childhood
A child’s skeleton is mainly made of cartilage at birth since it is softer and more flexible; thus, it makes the childbirth safer for the mom and child.
The cartilage will gradually transform into bone through the process of ossification. The high cartilage content at birth makes the skeleton lighter.
Ossification continues as the child grows and develops, and the cartilage is replaced by bone. The bone density is higher than cartilage, increasing the skeleton weight. Physical activity and proper nutrition are crucial during this early childhood to create a solid skeletal foundation.
Adolescence and Young Adulthood
Puberty starts with rapid growth spurts and significant hormonal changes, both aspects that directly affect skeletal weight.
Humans and most animals have growth plates at the end of long bones, which allow for longitudinal bone growth; they make you taller.
During this time, the bones become denser and longer, which contributes further to skeletal weight increase.
Hormones like estrogen and testosterone are critical in the mineralization and growth of bones during puberty.
Depending on genetics, individuals usually reach their peak skeletal mass around their late teens or mid-twenties.
During this age, bone density and strength are at their peak, and the body needs adequate calcium, vitamin D, and exercise to achieve the ideal bone mass.
Bone density stabilizes during early adulthood (25-35), but the body remodels the bones to meet its requirements.
Lifestyle factors such as diet and exercise can cause subtle changes in bone mass during his window, but it remains at about 15% of the body weight.
Aging and Old Age
Once people get past 40, the rate of bone breakdown outpaces bone formation, which leads to a decrease in bone density and strength. Hormones decrease, especially estrogen in women and testosterone in men, further contributing to bone loss.
The risk of bone and joint conditions like osteoporosis increases in old age. Osteoporosis is a condition that weakens bones and makes them more susceptible to fractures. The structural and mass changes decrease the skeletal weight as you age.
Older people often participate in fewer activities, which further contributes to decreased skeletal weight. This can lead to a condition known as frailty, where overall physical strength and bone density decline significantly.
Composition of the Human Skeleton?
What makes up the human skeleton to get to the 10.5kg average? The human skeleton has various parts that allow it to anchor muscles, support the body organs, and facilitate movement. You can divide the skeleton into two parts as follows;
1. Axial Skeleton
The axial skeleton is the middle section of the skeleton, and it includes bones that make up the longitudinal axis of the body. These include the ribcage, skull, and vertebral column.
The skull comprises many hard bones that protect the brain and the eyes. It also houses other sensory organs like the ears, nose, and tongue.
It has cranial bones and facial bones that create its structure which contributes to what a person’s face looks like.
The vertebral column or spine constitutes 33 individual bones called vertebrae. The spine is categorized into regions; thoracic, neck, lumbar, pelvic, and coccygeal.
The spine provides support and protection for the spinal cord while allowing for movement in the upper body.
The rib cage consists of the thoracic vertebrae, sternum, and ribs. They encircle the thoracic cavity to protect the lungs and heart from physical damage.
2. Appendicular Skeleton
The appendicular skeleton comprises the bones that form the arms and legs and supporting structures that connect them to the axial skeleton.
The upper limbs include the bones of the arms, forearms, wrists, and hands. The humerus is the bone of the upper arm, between the elbow and shoulder, while the radius and ulna make up the forearm.
The wrist has 8 small bones called carpals, while the hand has 27 small bones that allow movement and grabbing.
The lower limbs comprise the bones of the thighs, legs, ankles, and feet. The femur is the thigh bone, while the tibia and fibula are the leg bones. The ankle comprises tarsal bones, and the foot includes metatarsals and phalanges.
The pelvic girdle is an area around the hip bones and sacrum. It supports the upper body’s weight and connects the lower limbs to the axial skeleton.
All these parts work together to facilitate all human movement and activities, from eating to sleeping and everything in between.
Bone marrow, ligaments, tendons, and cartilage are connective tissues that hold the bones in place and pull them to cause movement.
You can take better care of yourself and your kids with this understanding of how much the human skeleton weighs.
The weight varies slightly based on sex, genetics, physical activity levels, and age, with the peak skeletal weight between 25 and 30 for most people.
The human skeleton comprises 206 bones in adulthood, which is critical for human life. You need it for even the most basic movements, so you must take the best care to keep it in perfect health. Get a proper diet and exercise for more bone density and stronger bones.