Alpha-1 antitrypsin (AAT) deficiency is a genetic disorder that increases your risk for lung and liver disease.

While there is no specific diet for AAT deficiency, eating the right foods and avoiding others can help you better manage the condition.

This article explains what to eat and avoid with AAT deficiency and provides a sample alpha-1 antitrypsin deficiency diet.

What is alpha-1 antitrypsin (AAT) deficiency?

AAT is a protein produced mainly in your liver that protects your lungs from being damaged by an enzyme that is released from white blood cells to fight infections (1).

Without enough healthy AAT, this enzyme destroys the air sacs in your lungs and causes lung disease.

Abnormal AAT can also buildup in the liver and cause damage that leads to liver cirrhosis or even cancer.

It’s an inherited disorder, meaning you inherit the condition from both your parents.

AAT affects an estimated 1.5–3% of people living in the United States and Europe (1).

AAT deficiency shares many of the same symptoms as chronic obstructive pulmonary disease (COPD) and emphysema.

Most people with AAT deficiency don’t know they have it and usually develop the first signs and symptoms of lung disease between 20 and 50 years old.

Symptoms of AAT deficiency include (1):

  • shortness of breath
  • repeated lung infections
  • persistent cough
  • phlegm or sputum production
  • red and painful spots on the thighs or buttocks

A simple blood test can confirm an AAT deficiency diagnosis, however, your doctor may perform additional tests to assess any damage to your lungs and liver.

From the results of these tests, your doctor can determine the best treatment plan for you according to your preferences and goals for care.

Alpha-1 antitrypsin deficiency diet

The connection between diet and improving health outcomes in people with AAT deficiency remains largely unstudied.

However, because 10–15% of people with AAT deficiency will develop severe lung and liver disease, diet is an important component for managing the condition (2).

Although the keto diet or ketogenic diet — a diet rich in fat, moderate in protein, and low in carbs — has been suggested to improve AAT deficiency symptoms, there is no research to support this claim.

Instead, eating foods that support liver and lung health while avoiding those that are damaging is essential.

Foods to avoid

You should avoid foods that can cause liver and lung inflammation and worsen your condition.

Saturated fats

Saturated fats are naturally found in animal-based foods and added to others.

These fats don’t necessarily cause inflammation but they can worsen inflammation that is already present with AAT deficiency.

However, not all saturated fats are created equal.

Saturated fats found naturally in dairy products don’t seem to increase inflammation and may actually decrease inflammation (3).

Conversely, saturated fats from highly processed foods like cakes, biscuits, sausages, bacon, and fast food can worsen inflammation (4).

These foods also tend to contain added sugars, excess sodium, and low amounts of fiber.

Added sugars

Added sugars — while not inherently bad — can cause harm to your liver when you consume them as excess calories.

This is because added sugars can increase a type of fat in your blood called triglycerides, which can build up in your liver and cause inflammation.

The American Heart Association recommends limiting added sugars to less than 6 teaspoons (25 grams) for women and 9 teaspoons (36 grams) for men (5).

Common sources of added sugars include candy, desserts, regular soda, pastries, and less obvious items, like barbeque sauce.

Still, it’s always good to check the food label for added sugar.

Alcohol

There is limited research on the effects of drinking alcohol with AAT deficiency.

However, because excessive alcohol use is a primary cause of liver cirrhosis, guidelines suggest that there is no known safe level of alcohol use for people with AAT deficiency (6).

Therefore, you should abstain from alcohol completely to reduce further harm to your liver and other organs.

It’s also recommended to avoid drugs that can harm the liver like ibuprofen and other non-steroidal anti-inflammatory drugs (NSAIDs).

Foods to eat

Many foods contain nutrients and certain compounds that protect your cells and organs against damage from excess inflammation and oxidative stress.

Fruits and vegetables

In addition to containing essential vitamins and minerals, fruits and vegetables contain beneficial plant compounds called polyphenols.

Polyphenols have potent antioxidant effects that neutralize harmful free radicals and protect your lungs and liver from damage (7, 8).

It’s best to consume a variety of fruits and vegetables — either fresh, frozen, or canned — of different colors to get the most health benefits.

Whole grains

Like fruits and vegetables, whole grains also contain a variety of vitamins, minerals, and polyphenols.

One study in people with COPD found that eating whole grains was independently associated with improved lung function (9).

A different study — this time in people with fatty liver disease — found significant reductions in liver inflammation for those who ate mostly whole grains compared with those who didn’t over 12 weeks (10).

Aim to eat at least half your grains as whole grains such as whole wheat, oats, quinoa, brown rice, and popcorn.

If you’re unsure whether a product contains whole grains, check the ingredient list. The first ingredient listed should contain the word “whole.”

Lean proteins

Protein has several essential roles in your body.

You need protein to support immune health, make important hormones and enzymes, maintain fluid balance, and for the growth of new tissues like muscle.

Protein is especially important for people with liver or lung damage from AAT deficiency to support health and reduce muscle loss.

Good sources of protein include:

  • Poultry: chicken, turkey, eggs
  • Meats: lean cuts of pork tenderloin, and eye of round, sirloin, and flank steaks
  • Dairy: cottage cheese, Greek yogurt, milk
  • Seafood: cod, oysters, salmon, scallops, shrimp, tilapia, trout, and tuna
  • Legumes: chickpeas, lentils, lima beans, navy beans, peas, pinto beans, soybeans, and peanuts
  • Nuts and seeds: almonds, cashews, chia seeds, flaxseeds, pine nuts, pistachios, pumpkin seeds, sunflower seeds, and walnuts

One-day sample alpha-1 antitrypsin deficiency diet

Here is a one-day sample AAT diet rich in fruits, vegetables, and lean proteins:

Breakfast: avocado spread across whole-grain toast and two scrambled eggs with spinach

Snack: hummus with sliced sweet peppers and carrot sticks for dipping

Lunch: grilled chicken breast sandwich with a side salad

Snack: cottage cheese with sliced peaches and sliced almonds

Dinner: pork loin, roasted potatoes, and Brussels sprouts

Use this sample meal plan to guide your choices as everyone has different needs and may not have the resources to purchase or regularly access these foods.

Alpha-1 antitrypsin deficiency and exercise

Like good nutrition, exercise is essential for overall health, but it becomes even more important with AAT deficiency for improving lung function.

In fact, research suggests that exercise capacity — the maximum amount of physical exertion that you can sustain — is the best predictor of health status and lung function in people with AAT deficiency (11).

Talk with your doctor about pulmonary rehabilitation — a supervised exercise and education program designed to help people with chronic lung diseases like AAT deficiency achieve a better quality of life.

The bottom line

AAT deficiency is a genetic condition in which your body doesn’t produce enough of AAT — a protein produced in your liver that protects your lungs.

While there is a lack of research on the topic, eating the right diet can help you better manage your condition and reduce harm to your liver and lungs.

With AAT deficiency, you should emphasize fruits, vegetables, and whole grains, and limit saturated fats from high-processed foods, excess added sugars, and added sugars.


Gavin Van De Walle, MS, RD, LN
Gavin Van De Walle, MS, RD, LN

Gavin Van De Walle holds a master's degree in human nutrition and bioenergetics. He is a registered dietitian who aims to arm the public with evidence-based nutrition recommendations so they can make their own educated and informed health decisions.