To understand the correlation between liver and blood glucose levels, let us understand the role of the liver in our body.
The liver is the heaviest organ in the body, weighing 1.4 kg and acting as the reservoir and processor of food. The main function of the liver is filtering the blood for utilisation, storage and supply of nutrients to the body.
Let us look at the process of blood filtering by the liver closely:
The heart pumps the nutrient and oxygen-rich blood to the liver.
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The liver utilises oxygen for storing and processing the nutrients such as carbohydrates, proteins, fats and vitamins from the consumed food.
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These nutrients get stored and processed within the structural and functional elements of the liver called lobules.
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The carbohydrates and fats are broken down into simple sugars and fatty acids which are either stored in the liver or utilised by the body when in need.
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If the body is not utilising the stored nutrients then the liver may be overloaded with nutrients leading to diseases.
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Along with nutrients, the blood reaching the liver may also contain toxins which are detoxified by the liver and sent to the kidney for excretion.
Apart from this, the liver also plays a key role in regulating the glucose levels in the blood.
But how does the liver affect blood glucose levels?
The liver not only stores glucose but also supplies glucose depending on the needs of the body.
This need of the body for storage or supply of glucose is determined by the hormones-
insulin and glucagon.
Let us understand the effect of the liver on blood glucose levels.
· How does the liver reduce blood glucose levels?
Post a meal, our blood is rich in glucose which is the chief source of energy for our body.
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A rise in blood glucose levels signals the pancreas to secrete insulin which is responsible for the regulation of blood glucose levels.
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In a non-diabetic person, insulin is released when there is high blood glucose and the glucose in the blood is converted into glycogen (the storage form of glucose) by the liver.
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This glycogen is stored for breakdown and uptake by the body when there is low blood sugar which can be during fasting – (for example: between meals) or in need of energy (for example – during a high-intensity workout).
We have understood how insulin and the liver help in reducing blood glucose levels when there are high levels of glucose in the blood.
· But how does the liver increase blood glucose levels?
The liver can increase blood sugar levels when there is a need for energy in the body.
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This process is mediated by the hormone glucagon which stimulates the release of glucose into the blood when there are low blood glucose levels.
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When fasting or in high need of energy, there is low blood glucose. So, the liver breaks down the stored glycogen and converts it to glucose for utilisation by the body.
Diseased liver and blood glucose levels:
In a healthy human body, insulin signals the liver for the uptake and reduction of blood glucose levels by converting glucose to glycogen.
However, in the case of diabetes, insulin function is impaired and leads to high blood glucose levels.
The coordination between insulin and the liver is affected in diabetes.
Diseases of the liver that are frequently associated with diabetes include:
· Non-alcoholic fatty liver disease
· Alcoholic cirrhosis
· Chronic hepatitis C (CHC)
· Hemochromatosis
Liver dysfunction and diabetes are closely linked because both the diseases are caused due to obesity and insulin resistance.
The majority of patients with NAFLD (Non-alcoholic Fatty Liver Disease) have type 2 diabetes and are known to aggravate each other.
· The common risk factors causing both diseases include obesity, fatty food and a sedentary lifestyle.
In patients with Liver cirrhosis which is one of the major diseases of the liver where the liver becomes fibrous due to excess alcohol consumption, type 2 diabetes can be developed due to insulin sensitivity.
· This type of diabetes which occurs secondary to cirrhosis is called Hepatogenous diabetes.
· About 96% of patients with liver cirrhosis may be glucose intolerant and 30% develop type 2 diabetes.
It can be understood that the correlation of liver disease and glucose metabolism are closely associated. Hence, in order to minimise the effects of liver dysfunction and diabetes leading to one another, it is important to keep the factors leading to the diseases in control.
Let us look at some of the common factors causing liver disease and ways to maintain a healthy liver.
