With the improvement of people's living standards and the change of dietary structure, fatty liver is becoming more and more common, and the corresponding patients are getting younger and younger. So, what exactly is fatty liver? What is the connection between fat and liver? And how to deal with it? This issue will take you to know fatty liver.
The role of the liver in fat metabolism
The liver is the largest internal organ in our body, and it is also the most important organ for the human body to carry out metabolism, and it is an indispensable and important part of maintaining the life activities of the human body. There are many chemical reactions that can occur within liver cells and have more than 500 functions. Nutrients such as glucose, fatty acids, amino acids, minerals, and vitamins absorbed by the small intestine after the human body eats are synthesized, decomposed, and distributed through the liver, and it can be said that the liver is a veritable "chemical factory".
Fat is one of the three major nutrients required by human beings, an important part of human tissues, and the main substance for storing energy in the human body. Fat is mainly distributed in the subcutaneous tissue, omentum, mesentery and around the kidneys.
1. Fat production
There are two sources of body fat, one is ingested from food and the other is synthesized directly in the body.
When we consume fat from food, the fat is hydrolyzed into glycerol and fatty acids in the small intestine through the digestion of bile (mainly secreted by the liver) and lipase, which are subsequently absorbed by the cells of the small intestine and enter the bloodstream, where they flow into the liver with the bloodstream. After fatty acids enter the liver, they will be taken up and utilized by liver cells, and some of them will be oxidized and decomposed to supply energy for themselves; Some of them synthesize fats, phospholipids, cholesterol, etc., and re-enter the blood from the liver, and are transported to various tissues and cells throughout the body with the blood circulation for storage and utilization.
When the human body consumes too much sugar and protein, liver cells will also convert excess glucose and amino acids in the blood into fat, which will be released into the blood, which will be transported to various tissues with the blood for storage and utilization. Of course, fat tissue in other parts of the body can also use blood sugar to synthesize fat, but most of it is still synthesized in the liver.
It can be seen that whether you consume fat directly from food or synthesize fat in the body itself, you can't do without the liver. Now that we know where fat comes from, let's move on to fat consumption.
2. Fat consumption
We all know that glucose is the main substance that provides energy for various tissues and organs of the human body. When the sugars in food enter the human body, they are digested, absorbed and hydrolyzed into glucose into the blood, resulting in an increase in blood sugar, at which point the liver will convert glucose into liver glycogen and store it in the liver, so that the blood sugar content remains stable. When the body consumes glucose and causes blood sugar to drop, liver glycogen will be broken down into glucose and enter the blood, keeping blood sugar stable. If the liver glycogen is not enough to meet the body's energy needs, then the body's stored fat begins to be used.
The fat in the body adipose tissue is hydrolyzed into glycerol and fatty acids under the action of lipase, which is released into the blood, and transported to various tissues with the blood to oxidize and decompose energy to produce energy, and the liver is the main place for oxidative decomposition of fatty acids to produce energy.
3. The role of the liver in cellular metabolism
Through the above analysis, we can know that fat is inseparable from the liver when it is digested and absorbed in the small intestine; After the fatty acids in the blood enter the liver, the liver cells can oxidize and decompose fatty acids to produce energy on the one hand, and on the other hand, they can also use fatty acids to resynthesize fats, phospholipids and other lipids, which are released into the blood again, and transported to other tissues and organs with the blood for storage and utilization.
It is worth mentioning that fats are insoluble in water and need to combine with apolipoproteins to form lipoproteins before they can enter the bloodstream for transportation. Apolipoproteins are mainly produced by liver cells, so fat transportation is also inseparable from the liver.
It can be said that the liver plays an important role in the digestion, absorption, decomposition, synthesis and transportation of fats.
How fatty liver is formed
So what's going on with fatty liver? Fatty liver is a lesion caused by the accumulation of fat in the liver due to various reasons. What causes fat to accumulate in the liver?
Needless to say, obesity is an important factor. Obese people accumulate fat in their bodies, and the amount of free fatty acids in their blood is high, and when the blood flows through the liver, a large amount of fat is synthesized. The amount of apolipoprotein delivered is limited, and the fat cannot be transported outside the liver in a timely manner, resulting in the accumulation of fat in the liver. Sugars can also be converted into fat, so a diet high in sugar can also cause fatty liver.
So don't thin people get fatty liver? A news item mentioned that a 42-year-old, 172cm tall, 138-pound thin man was found to have mild fatty liver during a physical examination. And this kind of person is not alone, it can be seen that obesity is not the only factor that causes fatty liver.
When the body consumes too little protein, resulting in a lack of amino acids necessary for the synthesis of apolipoprotein, apolipoprotein synthesis is blocked, the ability to transport fat is weakened, and fat accumulation in the liver is also caused.
Fasting or excessive dieting can also lead to fatty liver hunger. When the human body is in a state of hunger for a long time, in order to make up for the lack of glucose, an energy-supplying substance, a large amount of fat stored in the body will be used, resulting in an increase in fatty acids in the blood, which will cause fat accumulation after entering the liver.
Long-term heavy alcohol consumption can also cause fatty liver. After alcohol enters the human body, a very small amount is excreted through breathing or urine, and most of it is metabolized and decomposed in the body, and the liver is the main metabolic organ. Long-term heavy alcohol consumption can cause liver cell damage, hinder the liver from releasing proteins, inhibit the decomposition and utilization of fatty acids, and lead to fat accumulation.
Diabetic patients do not secrete enough insulin in their bodies and cannot send glucose into their cells to decompose and supply energy, so they can only use the fat stored in the body to supply energy, resulting in an increase in fatty acids in the blood, and a large amount of fat is synthesized and accumulated in the liver to form fatty liver.
In addition, since the metabolic pathway of the drug is primarily the liver, some drugs taken may cause fatty liver by inhibiting protein synthesis. In summary, fatty liver may be caused by factors that can lead to high levels of fatty acids in the blood, decreased apolipoprotein synthesis in the liver, and weakened ability of the liver to break down fatty acids.
What to do if you have fatty liver
Under normal circumstances, the fat in hepatocytes generally does not exceed 5% of the liver weight, and more than 5% is considered fatty liver. 5% to 10% have mild fatty liver, 10% to 25% have moderate fatty liver, and more than 25% have severe fatty liver. Most patients with fatty liver do not have obvious symptoms, but if they are not controlled and allowed to develop, they may slowly progress along the trend of "fatty liver-steatohepatitis-liver fibrosis-cirrhosis-liver cancer", so it is necessary to pay close attention to it and treat it as soon as possible.
We know that there are many causes of fatty liver, so there are naturally different ways to deal with fatty liver caused by different causes. At present, there is no specific drug for the treatment of fatty liver, so the key is to find the cause of fatty liver, remove the cause, eat a reasonable diet, and enhance exercise.
For fatty liver caused by obesity, it is natural to change the lifestyle, "keep your mouth shut and open your legs"; For fatty liver caused by long-term heavy drinking, abstinence from alcohol is the most important; For fatty liver caused by malnutrition or dieting, attention should be paid to a reasonable diet to maintain a balanced nutrition; For fatty liver caused by diabetes, diabetes should be controlled and treated as soon as possible, with reasonable diet, low sugar and low fat, and appropriate exercise. In addition, medication-assisted treatment can also be taken under the guidance of a doctor.
Finally, I hope everyone can protect their "careful liver" and stay away from cellulite!
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