The Basics of Blood

Blood is fundamental to how our bodies function, so its composition can have a profound impact on our long-term health. Here's the lowdown:

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What is blood? 

Blood is an essential component in the human body. It is made up of two key components: plasma and blood cells. 

Plasma makes up around 55-60% of your total blood volume. This fluid component of blood is mostly water (90%) and is an important delivery system in the body. Several other components such as proteins, sugar molecules, fats and electrolytes are also dissolved in the plasma.

Blood cells make up the remaining 40-45% of your blood volume, the majority of which is red blood cells. Red blood cells contain a protein called hemoglobin which is responsible for the red hue of blood. These cells are created in your bone marrow in response to a hormone called erythropoietin. White blood cells and platelets make up less than 1% of your blood volume, and these cells are needed for immunity and blood clotting. 

Your blood runs through a network of blood vessels and makes up about seven to eight percent of your total body weight. An average male has just over 5 litres of blood (11 pints), whereas the average female has around 4 litres (9 pints).

What does blood do?

Transport oxygen

One of the main functions of blood is to transport oxygen from the lungs to every cell in the body, and then to return carbon dioxide to the lungs for removal. Healthy red blood cells, with good hemoglobin levels are needed to ensure that oxygen is carried around the body effectively.  

Transport nutrients and hormones 

Once food has been digested, it’s absorbed into the bloodstream in the form of glucose, amino acids, fatty acids, vitamins and minerals. Your blood then delivers these nutrients where they are needed.

Hormones are also transported in the bloodstream. These are messenger molecules that ensure communication and control between different systems and organs in the body.  

Delivery of waste products to the kidneys and liver 

Most processes in our bodies result in waste products that need to be removed. Blood transports these waste products to the kidneys or liver. These organs are essential for safe removal. 

Blood clotting 

When you’re injured, you will bleed as a result of a tear in a blood vessel. Blood clotting, also known as coagulation, covers over the tear to stop blood loss. This process occurs because platelets and proteins called fibrins work together to plug the injured area and prevent blood loss. 

Blood helps regulate temperature

Our internal temperature needs to be maintained between 36.5°C and 37.5°C. Blood helps to regulate this by controlling the diameter of the blood vessel. The tightening ((called vasoconstriction) or relaxation (called dilation) of the blood vessel moves the blood closer to or further away from the surface of the skin. The closer to the skin, the more heat is lost.

Blood keeps us healthy

The white blood cells found in blood protect the body from disease. When pathogens, such as bacteria or viruses enter the body, your white blood cell count will increase significantly. White blood cells are able to fight off threats. 

Where is Blood Found? 

Blood circulates through the body through a system of blood vessels called arteries, veins and capillaries. Blood found in arteries is usually rich in oxygen and nutrients (with the exception of the pulmonary artery) and carries blood away from the heart. Blood found in the veins, on the other hand, is being carried towards the heart and is generally deoxygenated (with the exception of the pulmonary vein). The capillaries are tiny blood vessels that form the bridge between arteries and veins within the tissues.

Should I do a blood test?

Because blood has so many functions it can be a good indicator of health. In a medical setting, blood tests are often diagnostic and there are many reasons why doctors require blood tests. 

Home blood tests are most often used as a form of primary prevention, identification of nutrient deficiencies and monitoring of chronic conditions. As a primary prevention tool, they can be incredibly useful to identify the early warning signs of conditions before they develop. 

For example, your lipid profile looks at the levels of bad cholesterol (LDL and triacylglycerides) and good cholesterol (HDL) in your blood. If these levels are off, it can be an early warning sign of heart disease. Similarly, if you have insulin resistance or prediabetes, a blood test can tell you earlier meaning you can take preventative measures. 

Blood Optimisation 

Blood tests can indicate the health of your blood as well as the functioning of your body as a whole. For this reason always focus on both: improving the functioning of your blood and optimising your blood profile for a healthier body. 

How to optimise your lifestyle for blood function.

Make sure you hydrate

Your blood is made up of mostly water. Therefore, it is essential that you consume enough of it. For the average adult, 8 glasses a day is enough, but some people might need even more.

Get enough iron, B12, folate and protein

Red blood cells are vital for oxygen delivery and preventing anaemia! Iron, vitamin B12, folate and protein are essential for building healthy red blood cells. Eat a balanced diet that provides you with what you need. If you struggle to hit those targets you might want to consider if supplementing is the approach for you.

How to optimise your blood profile for health

Pick the right kind of carbs

A diet high in refined carbs can affect your HBA1C as well as your triglyceride levels which are indicators of type 2 diabetes and heart disease respectively. Swapping processed starches and sugary foods for whole grains, fruit, vegetables and legumes is a good place to start. 

Avoid saturated and trans fats

A diet high in saturated and trans fats has been linked with an altered lipid profile and can result in higher LDL (bad) cholesterol levels. Mono- and polyunsaturated fats - those found in olive oil, nuts, seeds, avocado and oily fish - can improve cholesterol levels and can result in higher HDL (good) cholesterol. 

Avoid alcohol

Alcohol has been linked with a higher risk of liver damage and can affect your lipid profile (especially triglycerides). 

Maintain a healthy body weight

Maintaining a healthy body weight and regular exercise can improve so many aspects of your health, including your liver function, heart health, and risk of type 2 diabetes. A reduced risk of these conditions will result in a more favourable blood profile. 

Getting a blood test can reveal vital insights as to your current health status and point you in the right direction towards better lifestyle choices for your optimum wellness. With SnapShot you can connect your genetic report with your blood report and find your personalised route to better health.

Discover SnapShot

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