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HDL42
Triglycerides180
ApoB110
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Alanine Aminotransferase (ALT)mg/dL
Gamma-Glutamyl Transferase (GGT)mg/dL
Alkaline Phosphatase (ALP)mg/dL
343 U/L very high
0 from your result
elevatedvery high
1normal 5 to 41500
what this means

343 is very high for AST, enough that the number itself is the problem.

this is the average reading · make it yours below

reading as

This level is usually treated as urgent. A result this far outside the range is normally checked by a doctor promptly, not at your next routine appointment.

You are 302 U/L over the normal ceiling of 41. That reads very high.

343 is very high. That is above the normal range for AST. How much it matters depends on the markers it travels with, which is what the sections below are rewritten against.

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Your BloodMarker report · Aspartate Aminotransferase (AST)

Aspartate Aminotransferase (AST) 343 U/L: Is That High?

Yes. 343 U/L is well outside the normal range for AST.

But a number alone is only half the story. Your Alanine Aminotransferase (ALT), Gamma-Glutamyl Transferase (GGT) and your risk factors decide how much it means. Tell it who you are.

Reviewed against ALF, NIH, Mayo Clinic, AGA guidelines · Last reviewed March 22, 2026

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YOUR NUMBERS

Normal: <40
Raised: 40-79
High: 80+

Values in U/L. Your Aspartate Aminotransferase (AST) of 343 is marked.

What they say together.

Aspartate Aminotransferase (AST) is read as part of a set. Add the ones printed next to it on your test and the figures below work themselves out, with the ranges this page uses for each.

U/LHIGH
U/LexampleNORMAL
U/LexampleRAISED
343 ÷ 38 =9AST to ALT ratio, the De Ritis ratio. Under 1 is the usual fatty-liver pattern; above 2 points at alcohol.
62 and 381.6GGT against ALT. GGT rising faster than ALT is the pattern that separates alcohol and bile flow from fat in the liver.
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Is Aspartate Aminotransferase (AST) 343 U/L Low, Normal, or High?

Aspartate Aminotransferase (AST) 343 U/L might be considered higher than typical reference ranges found in many laboratory reports. This specific level suggests an elevated amount of this enzyme in your system, which often warrants further attention and discussion with a healthcare provider.

While exact 'normal' ranges can vary slightly between labs, a reading of 343 U/L usually indicates an increased activity of this particular protein. Understanding this number is an important step in exploring what it could mean for your overall well-being and cellular health.

This value serves as a signal, inviting you to learn more about your body's intricate processes.

what this page cannot tell you

The AST/ALT ratio above 2:1 suggests alcoholic liver disease. Near 1:1 points to non-alcoholic fatty liver. Which is yours?

This page has not been given your ALT, so that half of the picture is missing here. It is describing the average reader with Aspartate Aminotransferase (AST), not you.

Read mine against my ALT →

An Aspartate Aminotransferase (AST) level of 343 U/L signals significant acute cellular injury, often indicating a serious and immediate health concern requiring urgent medical attention. This value is critically elevated, vastly exceeding the normal range and suggesting substantial damage to cells where AST is abundant.

At this markedly elevated level, primary suspects include acute liver inflammation or injury, such as from severe viral hepatitis, significant alcohol-related damage, or adverse reactions to certain medications. Additionally, profound damage to skeletal muscle, like in rhabdomyolysis from severe trauma or intense exertion, can also drive AST to such heights.

Immediate medical evaluation is essential, typically involving further blood tests such as Alanine Aminotransferase (ALT), bilirubin, and alkaline phosphatase to help pinpoint the organ of origin and assess overall liver function.

A Creatine Kinase (CK) level is crucial if muscle injury is suspected, and imaging studies, like an abdominal ultrasound, might also be ordered. While an AST of 343 U/L is alarming, it’s important to understand that with prompt diagnosis and appropriate treatment, many underlying causes are manageable, emphasizing the urgency of complete follow-up and adherence to medical advice, even if you feel relatively well.

The liver and Aspartate Aminotransferase (AST) LIVER Produces Aspartate Aminotransferase (AST) Blood supply Bile output Elevated Aspartate Aminotransferase (AST) may indicate liver cell damage or stress
for your numbersThe section below is written for 343 against a general adult target. What 343 means for you depends on the rest of your lipids and your other risk factors. Your report starts from your whole picture, not one line.
for your numbersThe risk below is the average one for this AST. Whether it applies to you depends on the rest of your panel, which the article has not been given. Add them and this stops describing strangers.

Hidden Risk of Aspartate Aminotransferase (AST) 343 U/L

An Aspartate Aminotransferase (AST) 343 U/L reading can sometimes point to underlying issues that might not yet have obvious symptoms. This enzyme is present in various tissues throughout the body, including the liver, heart, muscles, and kidneys.

When cells in these tissues are damaged, AST can be released into the bloodstream, causing its levels to rise. A higher AST level, like 343 U/L, may suggest that some cellular distress is occurring, even if you feel perfectly fine.

It's a sign your body might be working harder than usual to manage or repair something internally. This elevation is not a diagnosis in itself, but rather an indicator that further investigation could be beneficial to understand the root cause.

what this page cannot tell you

AST and ALP together distinguish between liver cell damage and cholestatic disease, which have completely different treatments.

This page has not been given your ALP, so it cannot tell you which of those you are. It is describing the average reader with Aspartate Aminotransferase (AST), not you.

Read mine against my ALP →

A serum aspartate aminotransferase level of 343 U/L signifies significant hepatocellular injury, far exceeding typical fluctuations. This extreme elevation points towards acute damage to liver cells, potentially leading to a cascade of complications.

The rapid release of AST suggests an ongoing, aggressive process that can impair the liver's crucial functions, including detoxification, protein synthesis, and bile production. Without prompt intervention, this can progress to hepatic inflammation, potentially causing jaundice, impaired clotting, and in severe, untreated cases, acute liver failure, characterized by encephalopathy and coagulopathy.

The magnitude of this elevation warrants immediate investigation into the underlying cause to prevent irreversible damage.

for your numbersThis section lists every reason AST moves, because on its own the number cannot say which is yours. The rest of your panel and a few risk factors would cross most of them off in a sentence.

This part is about the number

Everything below explains what raises Aspartate Aminotransferase (AST). It cannot tell you which of them is yours.

Your test can. Every marker on it is read against every other one, which is where the answer actually lives.

PDF or a photo of the printout · read in seconds

What Does a Aspartate Aminotransferase (AST) Level of 343 U/L Mean?

When your Aspartate Aminotransferase (AST) is at a level like 343 U/L, it's natural to wonder what exactly that signifies for your body. AST is an enzyme, a type of protein, that helps cells function by speeding up certain chemical reactions.

It's especially concentrated in the liver, but also found in significant amounts in the heart, skeletal muscles, and kidneys. An elevated AST value, such as 343 U/L, typically suggests that there has been some kind of damage to cells in one or more of these organs.

When cells are injured, their contents, including AST, can leak into the bloodstream. This means the higher the level, the more extensive or acute the cellular damage might be. For instance, if the liver cells are experiencing inflammation or injury, they release AST.

Similarly, muscle injury or certain heart conditions could also lead to an increased Aspartate Aminotransferase level. It's like a signal from your internal systems, indicating a need for a closer look at what might be causing cellular stress.

This information provides a starting point for understanding your health and engaging in a comprehensive discussion with your healthcare team about potential next steps.

An AST reading of 343 U/L is most plausibly linked to acute viral hepatitis, such as Hepatitis A, B, or E, where viral replication directly causes widespread liver cell lysis.

Certain medications, particularly acetaminophen or statins taken in excess or by susceptible individuals, can also precipitate this level of AST elevation through direct hepatotoxicity. Less commonly, but still relevant at this range, is a severe bout of alcoholic hepatitis, where chronic alcohol abuse leads to acute inflammatory damage.

Ischemic hepatitis, due to severely low blood flow to the liver, could also manifest at this level, often in the context of shock or severe dehydration.

Your AST 343 means different things depending on your other markers

AST + ALT
The AST/ALT ratio above 2:1 suggests alcoholic liver disease. Near 1:1 points to non-alcoholic fatty liver. Which is yours?
AST + ALP
AST and ALP together distinguish between liver cell damage and cholestatic disease, which have completely different treatments.
AST + Creatine Kinase
If your CK is also high, your elevated AST might be from muscle damage, not liver damage at all.
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The part one number cannot show
Your AST of 343 means different things depending on its companion markers.
Your full panel shows which story is yours.
See what is driving yours →

Lifestyle Changes for Aspartate Aminotransferase (AST) 343 U/L

Addressing an elevated Aspartate Aminotransferase (AST) 343 U/L often involves looking at various aspects of your daily life beyond just what you eat. Regular physical activity, for example, plays a crucial role in overall health, but the type and intensity of exercise can also influence enzyme levels.

Overexertion, particularly intense or prolonged workouts, can sometimes temporarily elevate AST levels due to muscle breakdown. Finding a balanced exercise routine that supports your body without causing undue stress is key.

Managing stress effectively is another significant factor. Chronic stress can impact various bodily systems, and while not a direct cause of AST elevation, it can contribute to overall inflammation and cellular distress.

Techniques like mindfulness, meditation, or spending time in nature can help regulate your stress response. Additionally, ensuring adequate, restorative sleep each night allows your body to repair and regenerate cells.

Sleep deprivation can contribute to systemic inflammation, which might indirectly influence enzyme levels. Limiting exposure to environmental toxins, such as certain chemicals or pollutants, can also support liver health and cellular integrity.

Making conscious choices about these lifestyle elements can be empowering steps in supporting your body's health and potentially influencing an Aspartate Aminotransferase reading. These adjustments are about creating a supportive environment for your body's natural healing processes.

With an AST of 343 U/L, immediate medical evaluation is paramount. Schedule an urgent appointment with your primary care physician or an emergency department. Further laboratory tests should include a complete liver panel (ALT, ALP, Bilirubin, Albumin, PT/INR) and viral hepatitis serologies.

A lifestyle review focusing on recent medication changes, alcohol intake, and potential exposure to infectious agents is critical. You will likely be referred to a hepatologist or gastroenterologist specializing in liver diseases.

Tracking your symptoms, such as fatigue, abdominal pain, or jaundice, and monitoring your hydration status are important interim measures.

for your numbersThe portions below are generic because the page does not know your body. Add your height and weight above and the fibre targets resize to you at once, a small preview of what the full report does with every number.

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What you actually get

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You have just spent a few minutes reading a page written for a number. Upload your whole test and you get the same thing written for your body: every marker read against every other, in the order they should be fixed, as something you read rather than a dashboard you have to decode.

  • Read in orderWhich number to deal with first, and which ones are only following it.
  • Written, not chartedThe same voice as this page, about your own blood, on your own page.
  • Every retest joins itThe line builds itself, so the next version shows what moved.

Sources

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