Understanding What Foods Are High in LTP Protein

November 20, 2025 •

4 min read

Lipid transfer proteins (LTPs) are found in many plant foods and are resistant to heat and digestion, a fact that differentiates LTP allergy from other plant-based allergies. For individuals with LTP syndrome, this means cooked or processed foods can still trigger a reaction, making it crucial to know what foods are high in LTP protein and require careful management.

Quick Summary

A detailed resource on identifying common and less obvious food sources containing high levels of lipid transfer proteins (LTPs) for people with LTP allergy, covering fruits, nuts, vegetables, and processed items.

Key Points

LTPs are Plant-Based Proteins: Lipid Transfer Proteins are a type of protein found in many plant foods, including fruits, vegetables, nuts, and cereals.
LTPs are Heat-Stable: Unlike allergens in Oral Allergy Syndrome, LTPs are resistant to heat and processing, meaning cooked or processed forms of food can still trigger a reaction.
Peel and Seeds are High in LTPs: The highest concentration of LTPs is often found in the peel and seeds of fruits and vegetables, but avoidance of the whole food is often necessary for sensitized individuals.
Processing Increases Concentration: Processed and concentrated forms of plant foods, like juices, jams, and dried fruit, can have higher levels of LTPs.
Co-factors Can Trigger or Worsen Reactions: Exercise, alcohol, and certain medications (NSAIDs) can act as co-factors, increasing the likelihood or severity of an LTP allergic reaction.
Reactions are Individual: Not all individuals with LTP allergy will react to every LTP-containing food; personal reactions can vary, so a personalized avoidance plan is essential.
Anaphylaxis is a Risk: Due to their stability and ability to cause systemic reactions, LTP allergies carry a risk of severe reactions, including anaphylaxis, for some individuals.

What Exactly Are Lipid Transfer Proteins (LTPs)?

Lipid Transfer Proteins (LTPs) are a family of proteins found in a wide variety of plant-based foods, including fruits, vegetables, nuts, and cereals. Their primary function within the plant is to protect against disease and pests by transporting lipids (fats). From a human health perspective, LTPs are significant because they are highly stable proteins, resisting degradation by heat, enzymes, and digestion. This resistance is a key factor in LTP allergy, as the proteins remain intact and can trigger an allergic immune response even after cooking, fermenting, or processing. This stands in contrast to Oral Allergy Syndrome (OAS), where allergens are often denatured by heat. LTP allergy is not as common as OAS but can lead to more severe, systemic reactions.

High-LTP Fruits and Their Processed Derivatives

Fruits are one of the most common sources of LTPs, with the highest concentration often found in the peel and seeds. For individuals with LTP allergy, this means that peeling the fruit may not always be enough to prevent a reaction, especially if the fruit is processed. The amount of LTP in a food can vary, which makes predicting a reaction difficult, so allergists recommend avoiding all forms of a trigger food.

Stone Fruits: Peaches, cherries, and apricots are well-known triggers for LTP allergy. The protein Pru p 3 from peaches is considered a marker allergen for the syndrome.
Apples and Pears: These common fruits contain LTPs, and reactions can occur from eating them raw or even in cooked and processed forms like applesauce or juice.
Grapes and Berries: Grapes, raisins, wine, and grape juice are significant sources of LTPs. Berries, including raspberries and blueberries, also contain LTPs.
Citrus Fruits: Oranges and tangerines have been implicated in LTP allergy.
Dried and Concentrated Fruits: The processing of fruits into dried forms (like raisins, dried fruit peel) or concentrated products (jams, juices, smoothies) can lead to a higher concentration of the protein, increasing the risk of a reaction.

Nuts, Seeds, and Legumes Rich in LTPs

Many tree nuts, legumes, and seeds are also major sources of LTPs, and cross-reactivity is common within this group for sensitized individuals. Again, the proteins are stable and not destroyed by roasting or other forms of processing.

Tree Nuts: Hazelnuts, almonds, and walnuts are frequently associated with LTP allergy, with specific LTPs like Cor a 8 (hazelnut) and Jug r 3 (walnut) being identified.
Peanuts: While technically a legume, peanuts contain the LTP Ara h 9, which is a known allergen, particularly in Southern Europe.
Seeds and Legumes: Mustard seeds and sunflower seeds can be triggers. Other legumes like lentils, green beans, and peas may also contain LTPs that cause reactions.

Vegetables, Cereals, and Miscellaneous Items

LTPs are present in a diverse range of plant-based foods, and reactions can be highly individual. Common triggers extend beyond fruits and nuts to include many vegetables and cereals.

Tomatoes: Both fresh tomatoes and concentrated products like tomato paste and pizza sauce are common culprits due to their high LTP content.
Leafy Greens and Vegetables: Lettuce, cabbage, fennel, parsley, and asparagus have all been associated with LTP allergy.
Cereals: Cereals like wheat, corn, and barley contain LTPs, and products derived from them, such as beer, can also cause reactions.
Specialty Foods: Items like goji berries and figs also contain LTPs and can trigger allergies in sensitive individuals.

The Role of Processing and Co-factors

Processing methods that involve heating or fermentation do not break down LTPs. This is a critical distinction from pollen-food syndrome, where heat often eliminates the allergen. For example, a person with LTP allergy to grapes may react to wine, and a person allergic to tomatoes may react to pizza sauce. Additionally, certain co-factors can increase the severity of an allergic reaction to LTPs. These include:

Exercise: Physical activity can exacerbate symptoms.
Alcohol: Consuming alcohol alongside an LTP-containing food can trigger a more severe reaction.
NSAIDs: Taking non-steroidal anti-inflammatory drugs like ibuprofen can enhance the allergic response.
Stress: High stress levels are also considered a co-factor.

Comparing Allergen Stability: LTP vs. PFS Allergens


Feature	LTP Allergens	Pollen-Food Syndrome (PFS) Allergens
Protein Stability	Highly stable and resistant to heat, processing, and digestion.	Labile, meaning they are easily broken down by heat and digestion.
Effect of Cooking	Allergic reactions can still occur with cooked or processed foods.	Cooking or heating the food often renders it safe to eat.
Common Triggers	Stone fruits (peaches), nuts (almonds), vegetables (tomatoes).	Raw fruits (apples, pears), vegetables (carrots), and nuts.
Reaction Location	Often systemic, with potential for severe reactions like anaphylaxis.	Typically localized to the mouth and throat (Oral Allergy Syndrome).

What to Do If You Suspect an LTP Allergy

If you experience allergic symptoms after consuming certain plant-based foods, especially in both raw and cooked forms, it is essential to consult a healthcare professional. Self-diagnosis is not recommended, as it can be difficult to distinguish LTP allergy from other food allergies. An allergist can conduct tests to determine the specific foods triggering your reactions. Depending on the severity of the allergy, they may recommend avoiding the specific foods entirely or suggest that some foods can be tolerated if peeled. Anyone at risk of a severe reaction (anaphylaxis) should be prescribed and carry an adrenaline auto-injector. Always follow the guidance of a medical professional for management and treatment.

Conclusion

Knowing what foods are high in LTP protein is a critical step for individuals diagnosed with LTP allergy. These proteins are present in a wide array of plant foods, and unlike other plant-related allergies, they remain active even after cooking or processing. Common offenders include stone fruits, various nuts, and vegetables like tomatoes and lettuce. Understanding the role of co-factors and the importance of professional medical advice is key to safely managing this complex food allergy. By being vigilant about your dietary choices and working with a specialist, you can minimize the risk of a reaction and improve your quality of life.

Consult an allergist for personalized management and dietary guidance regarding LTP allergy.

Frequently Asked Questions

No, Lipid Transfer Proteins are known to be heat-stable and are not destroyed by cooking or other processing methods like fermenting or pasteurizing. For people with LTP allergy, this means both raw and cooked foods can be problematic.

No, LTP allergy is distinct from Oral Allergy Syndrome (OAS). OAS allergens are typically broken down by heat, causing reactions only to raw food, while LTP allergens are stable and can cause more severe, systemic reactions from both raw and processed foods.

Common high-LTP foods include nuts like almonds, hazelnuts, and walnuts; stone fruits such as peaches, cherries, and apricots; vegetables like tomatoes and lettuce; and cereals such as wheat and barley.

Yes, processed foods like jams, juices, and dried fruits can contain high concentrations of LTPs because the protein is not destroyed during processing and may be more concentrated in these products.

Co-factors are external elements that can increase the severity of an LTP allergic reaction. Common examples include exercise, consuming alcohol, taking non-steroidal anti-inflammatory drugs (NSAIDs), and stress.

Not necessarily. Reactions are highly individual, and some people may only react to a small number of LTP-containing foods. An allergist can help you identify your specific trigger foods, and you should only avoid the ones that cause symptoms.

Diagnosis of LTP allergy is done by a healthcare professional, typically an allergist. It involves a review of your symptoms and can include skin prick tests or component-resolved diagnosis (CRD) to identify specific LTPs causing the reaction.