Total Blood In the Human Body: Everything You Should Know

We all have heard that blood is the lifeline of the human body. It is a dynamic and complex fluid that sustains every cell and organ. 

From transporting vital nutrients, oxygen, hormones, and waste products, to defending against infections and helping maintain the body’s temperature, blood in the human body does it all. 

Have you ever heard of it? 

On average, approximately. 4.5 to 6 liters of blood circulate through the adult’s body, accounting for about 7-8% of total body weight. Still, if you have ever pondered: 

• How much blood do we have? 

• What determines this amount?

• How does blood change under different circumstances?

Also read:

 https://redcliffelabs.com/myhealth/blood-test/the-impact-of-natural-24-hour-fluctuations-on-blood-test-results/ 

Today’s blog sheds light on the fascinating world of human blood volume, its components, the factors that influence it, and its critical role in health and survival. 

Here is a general guideline: 

Blood volume varies slightly by gender due to factors such as age, health conditions, height, and weight. 

Adult men: 5 -6 liters (approx 1.3 to 1.6 gallons). This is due to their larger body size and greater muscle mass. 

Adult women: 4.5 liters (approx. 1-1.3 gallons). Adult females typically have less blood than males due to the direct effect of sex hormones and iron status. 

Children: The amount of volume depends on age and size (approx 80-90 mL per kg of body weight. 

Newborns: Approx. 240-350 mL (0.2 -0.3 liters)

Pregnant women: Blood volume tends to increase significantly during pregnancy by 30 % to 50% to support the fetus. 

Blood In the Human Body: Understanding Blood Volume as a Percentage of Body Weight

Blood makes up about 7-8% of an adult body’s weight. In infants, this percentage can be as much as 9-10%, and for children, it can be slightly higher (8-9%). This variation occurs due to differences in the body composition and metabolic needs. 

Quick Blood Trivia: You Might Like to Know

Your bone marrow produces about 2 million red blood cells every second. This constant renewal helps maintain your blood volume and function. 

What are the components of blood?

Blood is not just a red liquid; it is a complex tissue composed of several essential components. Let’s discover them in detail. 

Plasma

Plasma is a pale yellow fluid that makes up about 55% of the human blood. It carries nutrients, hormones, proteins, waste products, and other substances. More than 90% of blood plasma is water, and the remaining 10% consists of dissolved substances. 

Red Blood Cells (RBCs)

Approximately 45% of the blood volume consists of red blood cells (RBCs). The primary function of RBCs is to transport oxygen from the lungs to the tissues. They also remove carbon dioxide for exhalation. 

White Blood Cells (WBCs)

White blood cells (WBCs) are a part of the immune system. It contains less than 1% of blood volume. The main role of WBCs is to defend against infection. 

Platelets

Platelets play a crucial role in helping blood clots form and wounds heal. They make up less than 1% of blood volume. 

Hence, by transporting nutrients, fighting infections, and stopping bleeding, these four components of blood keep you alive. 

Total Blood in the Human Body: How the Body Responds to Blood Loss

A healthy adult can lose about 470 mL (one pint) of blood without serious harm. This is called tolerable loss. Losing more than one pint of blood can result in symptoms such as dizziness, confusion, rapid heartbeat, and eventually shock, and requires immediate medical attention. This is called a serious loss. 

1. Compensated blood loss

When you lose a small or moderate amount of blood, such as after a minor cut or injury, your body responds to protect itself. To maintain a steady blood pressure, your heart beats faster, and your blood vessels constrict. This allows the brain and vital organs to receive sufficient blood, enabling your body to remain safe.

2. Decompensated blood loss

In severe blood loss, your body’s compensatory mechanism may fail, causing low blood pressure, reduced oxygen delivery to tissues, and ultimately, organ failure. Therefore, an immediate medical intervention is needed to prevent serious complications. 

6 Main Factors that Affect Blood Volume 

Several factors that can increase or decrease blood flow in the human body include: 

• Body size and composition: The volume of blood is greater in larger and more muscular people. 

• Sex: Compared to females, males typically have more blood due to their larger body size and greater muscle mass. 

• Pregnancy: Blood volume increases significantly by 30% to 50% in pregnancy to support the growth of the fetus. 

• Altitude: Individuals living at high altitudes may have an increased blood volume and red blood cell production to carry more oxygen. 

• Hydration: Staying hydrated is essential. Dehydration means the loss of water that the body takes in. Plasma is 90% water; fluid loss shrinks the total volume of plasma.

• Medical conditions such as anemia, heart failure, kidney disease, and severe bleeding lower blood volume. 

Why Does the Volume of Blood In the Human Body Matter? 

Maintaining the right amount of blood volume is essential because: 

• Oxygen and nutrient delivery: Blood carries oxygen from the lungs and delivers nutrients absorbed from the digestive system to every cell in the body. 

• Waste removal: Blood transports waste products such as carbon dioxide and urea to the kidneys and lungs, where they are removed from the body. 

• Temperature regulation: Blood distributes heat throughout the body. Thus, it helps regulate your body temperature. 

• Immune defense: Antibodies and white blood cells in the blood protect against infections and diseases. 

• Clotting and healing: Platelets and clotting factors help stop bleeding and promote healing after injury. 

Also read: https://redcliffelabs.com/myhealth/blood/the-blood-type-diet-eat-the-right-for-your-type/

How to Book A Blood Test From Home- Redcliffe Labs Guide 

Redcliffe Labs enables you to monitor your health with affordable, comprehensive checkups and blood tests. Call 898 898 87 87, or download the Redcliffe Labs mobile app to schedule your test at your convenience. 

Step-by-step information on booking a blood test online from Redcliffe Labs. 

1. Visit the official Redcliffe Labs website: https://redcliffelabs.com/.

2. Search for the specific test you need. 

3. Add the test to the cart. 

4. Complete the payment process online.

5. You will receive confirmation through SMS and WhatsApp.

Free home sample collection and fast, reliable test results will be delivered within a stipulated time. 

Conclusion

Understanding the role of total blood in the human body highlights just how vital this remarkable fluid is for your health and well-being. Blood is your body’s lifeline, transporting oxygen and nutrients, supporting your immune system, and carrying away waste products.

With Redcliffe Labs, taking care of your health is simple. Whether you book your test online, use the mobile app, or call in, you can take comfort in the convenience of home sample collection and the fast, reliable results.

FAQs:

What happens if your body loses up to 15% of blood?

If your body loses up to 15% of its total blood volume, it may lead to a mild increase in heart rate, a slight rise in breathing rate, and you may feel anxious or lightheaded. 

What happens if you lose 15- 30% of blood?

Losing 15-30% of blood is called moderate loss. Symptoms associated with moderate loss are rapid breathing, pale skin, fast heart rate, and dizziness. 

What are the common symptoms associated with severe blood loss?

Severe blood loss is a medical emergency, indicating that your body has lost more than 30-40% of your total blood volume. It can cause a drop in blood pressure, confusion, a weak pulse, and the risk of organ failure. 

What does critical blood loss mean?

Critical blood loss means more than 50% of blood is lost, and prompt transfusion and resuscitation are required.