Foods to Avoid if You Have High Ammonia Levels

October 10, 2025 •

4 min read

Approximately 90% of adult cases of hyperammonemia, or high ammonia levels, are linked to liver disease such as cirrhosis. To manage this serious condition, it is vital to know which foods you should avoid if you have high ammonia levels to reduce the strain on your liver and prevent toxic buildup that can affect the brain.

Quick Summary

High ammonia levels are toxic to the central nervous system, often a result of impaired liver function. Restricting specific dietary components, particularly high-protein sources and processed foods, can help manage levels. This involves carefully choosing protein sources and limiting foods that increase the metabolic burden on the liver, as part of a medically supervised nutrition plan.

Key Points

Restrict Protein Intake: Limiting high-protein foods like red meat, eggs, and certain seafood helps control ammonia production.
Favor Plant-Based Protein: Opt for vegetable and low-fat dairy protein over animal sources to lower ammonia levels and promote better gut health.
Avoid Alcohol Completely: Anyone with liver disease causing high ammonia levels must avoid all alcohol, as it is a major liver toxin.
Limit Processed and Salty Foods: High sodium and processed ingredients can worsen fluid retention associated with liver disease.
Consult a Professional: A personalized diet plan should be developed in consultation with a doctor and dietitian to ensure proper nutrition while managing ammonia levels.

The Connection Between Diet and High Ammonia

Ammonia is a waste product created when the body breaks down protein. Normally, the liver converts this toxic substance into urea, which is then safely eliminated by the kidneys. When liver function is compromised, this process fails, causing ammonia to accumulate in the bloodstream. A high-protein diet exacerbates this issue, leading to a buildup that can cause significant neurological problems, a condition known as hepatic encephalopathy. For individuals with a healthy liver, high protein intake is generally managed without issue. However, for those with liver disease or certain metabolic disorders, dietary adjustments are critical.

Foods to Limit or Avoid Due to High Protein Content

One of the most important dietary changes is controlling protein intake, particularly from certain sources that can be harder on the liver. The goal is to provide enough protein to maintain muscle mass and nutritional status without overloading the system.

Red Meat: Beef, pork, and other red meats are dense sources of protein. Studies show that replacing meat with plant-based or dairy proteins can reduce ammonia generation.
Organ Meats: Offal like liver, kidney, and brain are extremely high in protein and should be avoided.
Certain Seafood: While some types of fatty fish are beneficial for liver health, many seafoods, particularly shellfish, are high in protein and should be limited.
Eggs: Eggs are a concentrated source of protein and must be managed as part of an overall controlled protein diet.
Full-Fat Dairy: Full-fat milk, cheese, and yogurt are high in both fat and protein, making them less suitable for those managing ammonia levels.
Legumes: Beans, lentils, and peas contain significant amounts of protein and should be monitored.
Nuts and Seeds: Like legumes, nuts and seeds are protein-rich and should be consumed in moderation and under a doctor’s guidance.
Soy Products: Products like tofu, tempeh, and edamame are also high-protein plant sources that need careful management.

Processed and Salty Foods

For individuals with liver disease, it's not just about protein. Processed and salty foods contribute to fluid retention (ascites), a common issue with compromised liver function.

Processed Meats: Bacon, sausage, deli meats, and hot dogs are packed with sodium and should be cut out.
Canned and Packaged Goods: Soups, canned vegetables, and packaged snacks are often loaded with hidden salt, which can worsen fluid retention.
Excessive Salt: Avoid adding extra salt at the table. Check food labels for sodium content and look for low-sodium alternatives.
Fast Food and Fried Food: These are typically high in unhealthy fats, which can be harder for a damaged liver to process, and also contain high levels of sodium.

Other Items to Avoid or Restrict

Alcohol: Alcohol is a major toxin for the liver and should be completely avoided by anyone with liver disease.
Sugary Foods: Excessive sugar, especially high-fructose corn syrup, can promote fat accumulation in the liver and should be limited.
Certain Supplements: Always consult a healthcare provider before taking any dietary supplements. Some, including certain vitamins, can be toxic to a damaged liver.

Understanding Protein Quality: Plant vs. Animal

Recent studies suggest that for patients with cirrhosis, replacing animal-based protein with plant-based or dairy protein can have beneficial effects on ammonia levels. This is believed to be related to the amino acid composition and fiber content of plant-based foods, which may help modulate gut microbiota and reduce ammonia absorption.


Feature	Animal-Based Protein	Plant-Based Protein	Implication for High Ammonia
Source	Meat, poultry, fish, eggs, dairy	Legumes, soy, nuts, seeds, whole grains	Plant-based may be easier to process for damaged livers
Fiber Content	None	High	High fiber helps increase nitrogenous waste excretion
Amino Acid Profile	Rich in methionine and tryptophan	Lower in methionine and tryptophan	Lower levels of these amino acids may reduce toxic byproducts in liver disease
Gut Health Impact	Can encourage bile-tolerant, ammonia-producing bacteria	Tends to promote a healthier, more diverse microbiome	A healthier gut can reduce systemic inflammation and toxins
Sarcopenia Prevention	Can be effective, but carries ammonia risk	Shown to help maintain muscle mass in some studies	Important to manage intake to support muscle without raising ammonia

Conclusion

High ammonia levels, often caused by liver disease, require careful dietary management to prevent serious complications like hepatic encephalopathy. A low-protein diet focused on plant-based and low-fat dairy sources, combined with strict avoidance of alcohol, processed foods, and high-sodium items, is the cornerstone of nutritional therapy. Close monitoring and collaboration with a healthcare provider or registered dietitian are essential to tailor the plan to individual needs and ensure adequate nutrition is maintained while controlling ammonia levels effectively. Remember that while diet plays a significant role, it is only one component of a comprehensive treatment plan that may include medication and other therapies.

For more detailed information, consult the guidelines provided by the American Association for the Study of Liver Diseases (AASLD) or a qualified medical professional.

Frequently Asked Questions

A low-protein diet is often recommended because protein breakdown is the primary source of ammonia production in the body. By reducing dietary protein, the metabolic load on a compromised liver is lessened, helping to prevent ammonia buildup.

Not all protein is bad. Adequate protein is essential to prevent malnutrition and muscle loss, particularly in liver disease. However, the type and amount of protein are critical. Plant-based and low-fat dairy proteins are often better choices than red meat or other heavy animal proteins.

No, diet is a key component but not the sole treatment. Managing high ammonia, especially in serious conditions like hepatic encephalopathy, often requires a combination of medication, dietary changes, and addressing the underlying cause with a healthcare provider.

Many vegetables are excellent choices. Vegetables are rich in fiber and beneficial compounds and contain less problematic amino acids than animal protein. Good examples include broccoli, asparagus, and leafy greens.

Alcohol is highly toxic to the liver and can severely impair its function. Since the liver is responsible for clearing ammonia from the blood, alcohol consumption directly contributes to higher ammonia levels and should be completely avoided.

Salty and processed foods can increase fluid retention and bloating (ascites), which is a common problem for people with liver disease. Managing salt intake is crucial to controlling these symptoms.

Hepatic encephalopathy is a brain function decline that occurs when the liver is unable to remove toxins, including ammonia, from the blood. The buildup of these toxins in the brain can cause confusion, disorientation, and other neurological symptoms.