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5 Human Organs that Weigh About 300 Grams

While most of our human organs, are small, there a couple that come close to weighing 300 grams. For the most part, the majority of them weigh less than 300 grams.

Still, we’ll look at the organs of the human body to see how they weigh in compared to 300 grams, and even share a little about the largest and smallest body organs.

1. Human Heart

The human heart is the most important body organ; without it life stops. The average heart beats 100,000 times a day and sends 2,000 gallons of blood through our body.

Without the heart, blood would not be able to flow through the 60,000 miles of blood vessels that feed our organs and tissues. When the heart is damaged, it has to work even harder at pumping to keep up with the body’s demand for blood.

All hearts do not weigh the same. A man’s heart weighs about 10 ounces (283 grams), while a woman’s heart weighs approximately 8 ounces (227 grams), making it no bigger than a fist.

Heart disease is one of the biggest killers of men and women, so it’s important to eat healthy, well-balanced meals to keep the heart healthy. Some other helpful habits to keep a healthy heart are to not smoke, and to keep your blood pressure and cholesterol levels at good, healthy numbers.

2. Kidneys

Our kidneys are appropriately named, as they are the shape of a kidney bean, and are correlated to our age and body size (height, weight, body mass index).

This means the larger we are, the larger our kidneys will be. When fully developed, our kidneys are the size of a fist. They are about 10 to 13 cm (4 to 5 inches) long, 5 to 7.5 cm (2 to 3 inches) wide and 2 to 2.5 cm (1 inch) thick. A male’s kidney can weigh up to 175 grams, and in women the kidney can weigh up to 190 grams.

The left kidney is slightly larger than the right. Since we are born with two of them, this makes the total weight of our kidneys around 300 to 400 grams.

3. Pancreas

The pancreas is a large gland located behind the stomach and next to the small intestine. It has two main functions: it releases digestive enzymes into the small intestine to help digest food, and it releases insulin and glucagon into the bloodstream.

A male’s pancreas is a little larger than a women’s, weighing about 144 grams, while the female pancreas weighs approximately 122 grams.

4. Spleen

The spleen is located below the rib cage on the left side of our body. It supports the body in many ways. It acts as a filter for blood as part of the immune system.

Old red blood cells are recycled there, and platelets and white blood cells are stored there. The human spleen measures about 7 x 5 x 2 inches, but differs depending on the individual. It’s estimated weight is .44 pounds, or a little less than 300 grams.

5. A Newborn’s Brain

The human brain is an astonishing organ that holds a great deal of memory, is susceptible to damage and still be adaptable to change. Men tend to have bigger brains than women.

This is due mostly to body size, as its size is based on the size of the body it’s in. It’s interesting that parts of the frontal lobe and limbic cortex, the parts of the brain associated with problem-solving and emotional regulation, tend to be bigger for women than for men.

The size of an adult brain is around 1300 to 1400 grams (3 pounds), but a newborn baby’s brain weighs about 350 to 400 grams (3/4 of a pound).

The Largest Body Organ

The liver is the heaviest internal organ in the human body, weighing about 3.43 pounds, (5 times the size of the heart).

As with some other organs, the liver’s size is dependent on the gender and the size of the individual. The larger the size of the body, the larger the liver. The liver’s size plays a big part in its role. It’s designed to regulate glycogen storage levels, break down toxins and clean our blood.

The Smallest Body Organ

There are two organs that have been identified as the smallest body organ.

The pineal gland is a small pea-sized structure located in the middle of the brain. It is responsible for producing and regulating some hormones in our body. It weighs about 172mg.

The lymph node removes excess fluid, absorbs fat and fatty acids and transports them to our circulatory system. It also creates white blood cells that helps the body fight against disease.

Lymph nodes are located in different parts of the body, including the neck, behind the ears, under the jaws and chin, under the armpits, and in the groin. They range in size from 2 millimeters to 1 to 2 centimeters long.