Q:

Curious about what recommendations are being made for sunflower oil avoidance in patients who are either 1) clinically allergic or 2) sensitized to sunflower seed. Many of my sesame allergic patients raise questions about other seeds, and I will occasionally test to fresh poppy seed, sunflower seed, and/or pumpkin seed to assuage their concerns about their children's range of "reactivity". However I do have a small number of patients who have either had overt clinical reactions to sunflower seed or moderately positive skin tests to fresh sunflower seed. Avoiding the seed is no big deal but avoiding the oil is quite prohibitive. The best reference I could find was from JACI 2000, Zitouni N et al, which looked at amounts of allergenic protein detected at each stage of refining sunflower oil and indeed there were "trace" amounts present in the final product. An older paper (JACI Halsey 1986) actually challenged two patients "anaphylactic" to sunflower with commercial sunflower oil and neither reacted. Are there any other references that would be helpful in making a recommendation to patients?

A:

Thank you for your recent inquiry.

Unfortunately there is no definitive answer to your question. There are reviews that deal with the issue, and perhaps the best of these are seen in Abstract Numbers 1, 3, and 4, which are copied for you below. These give strong reassurance that allergic reactions to sunflower oil are very rare because of the refinement process. However, they do note that allergic reactions to sunflower oil have been reported (see Abstract Number 2 copied below), and therefore the issue as to whether or not such reactions can occur is dependent on the particular oil encountered (to what degree it has been refined) as well as the level of sensitivity of the patient. Thus, in the end analysis, a decision regarding whether or not to avoid sunflower oil in a patient sensitive to sunflower seed is one that is based on clinical judgment. Unfortunately there is no practical, objective way to assess this risk in a given patient.

However, as noted, in the vast majority of instances it would be safe to ingest sunflower oil in a patient with sunflower seed allergy due to the refinement of the oil as noted in the reviews cited below.

Thank you again for your inquiry and we hope this response is helpful to you.

(1) Food and Chemical Toxicology
Volume 38, Issue 4, April 2000, Pages 385-393
Review
Allergenicity of refined vegetable oils
R.W.R Crevela, , M.A.T Kerkhoffb, M.M.G Koningb
Purchase
a
Toxicology Unit, Unilever Safety and Environmental Assurance Centre, Unilever Research, Colworth House, Sharnbrook, Bedford MK44 1LQ, UK
b
Unilever Research, 120 Olivier van Noortlaan, 3010 AT Vlaardingen, The Netherlands
Accepted 20 September 1999. Available online 13 September 2000.
Abstract
Several commercially important refined vegetable oils are derived from plants which are recognized as potent food allergens (e.g. peanut, soy). Full refining of oils results in the almost complete removal from oils of protein, which is responsible for allergic reactions. However, it is uncertain whether the minute amounts remaining could provoke allergic reactions in highly susceptible individuals. This has led to a vigorous debate about the safety of refined oils and specifically whether to label each oil individually because of the potential risk of allergenicity. Peanut oil has been the most thoroughly studied. It has been shown, in well-designed studies, that refined peanut oil can be safely consumed by the vast majority of peanut-allergic individuals, whereas unrefined oil can provoke reactions in some of the same individuals. However, some other studies report cases of allergic individuals reacting to oils, which are presumed to be refined. While it is likely that the discrepancy between these observations is due to differences in the processing of the oils, and possibly the protein content, this has not been formally demonstrated. Few data exist on the potential allergenicity of other edible vegetable oils; what data there are suggest that the major oils (soy, maize, sunflower, palm) do not provoke allergic reactions in susceptible individuals. Determining the content and immunoreactivity of the residual protein of refined oils is crucial to assessing the allergenic risk they present. Current methodology is inadequate and has not been validated for use with oils and aqueous extracts from oils. Little is known about the importance of different processing steps on allergenicity, although this information is crucial to risk assessment, particularly when considering process modifications. Available data suggest that the protein content of crude oils is of the order of 100–300 μg and that refining results in levels up to about 100-fold lower. The review concludes that peanut oil, and by extrapolation other edible vegetable oils, presents no risk of provoking allergic reactions in the overwhelming majority of susceptible people. However, there is a need to standardize and validate methodology for measuring the protein content and immunoreactivity of such so that they can be used to maintain process specifications. Thresholds of reactivity to allergens in man also need to be established in order to assess fully the risk from very small amounts.

(2) Food allergy to sunflower oil in a patient sensitized to mugwort pollen
Allergy
Volume 49, Issue 7, pages561-4, 1994
G. Kanny1,*,

(3)Update on threshold doses of food allergens: implications for patients and the food industry
Current Opinion in Allergy & Clinical Immunology:
June 2004 - Volume 4 - Issue 3 - pp 215-219
Abstract
Purpose of review: The purpose of this review is to bring the reader up to date on the importance of assessing a food's lowest observed adverse-effect level (LOAEL) with two aims. Firstly, to help industry choose tests with a level of sensitivity capable of detecting food allergens hidden in industrial products. Secondly, to specify protective measures for highly allergic individuals in order to prevent recurrent severe anaphylaxis. The review also seeks to highlight the present issues and unsolved questions.

Recent findings: Thanks to standardized oral-provocation tests (double-blind placebo-controlled food challenges), LOAELs have been identified for many IgE-dependent food allergies. Most studies concern the pediatric population. Data is available for milk, egg, peanut, wheat flour, and sesame. The LOAELs are commonly in the range of 1-2 mg of natural foods, representing a few hundred micrograms of protein. These minimal reactive doses characterize about 1% of people allergic to milk, egg, or peanut. The level at which no observed adverse effect is seen might be a few tens of micrograms of protein for peanut. At the present time, allergy to oil seems to be restricted to unrefined cold-pressed oils.

Summary: Concerning IgE-dependent food allergies, the threshold dose inducing symptoms is now known to vary a great deal according to the individual. A reactive dose of less than 65 mg characterizes 16 and 18% of patients allergic to egg or peanut. Less than 30 mg of milk proteins characterizes 5% of those allergic to milk. For milk, egg, and peanut, 1% of patients have a very low threshold, about 1 mg. Such data emphasize the necessity of using detection tests with a sensitivity better than 10 parts per million. The modifications of allergenicity undergone by protein ingredients that are now commonly introduced into industrially made products are not yet sufficiently known. A better knowledge of the reactive doses of these proteins is needed.

(4) Allerg Immunol (Paris). 2002 Mar;34(3):91-4.
[Allergenicity of oils].
[Article in French]
Frémont S, Errahali Y, Bignol M, Metche M, Nicolas JP.
Source
Laboratoire de Biochimie Médicale et Pédiatrique, Faculté de Médecine de Nancy, 9, avenue de la Forët de Haye, BP184, 54500 Vandoeuvre-les-Nancy, France.
Abstract
Cases of allergy to the oils of groundnut, sunflower, soya and sesame have been described in the literature. In parallel, other authors have affirmed that these oils are not allergenic. The objective of this article is to make the point on this question, to cite the procedures to which the seeds are submitted to extract the oil, to remember that the oils are not composed only of triglycerides and to describe the results of our work. Allergy of oils is a subject that is constantly submitted to controversy and the bibliography does not cease to give contradictory examples. This may be explained by the variations in extraction procedures used by the manufactures, as well as by the conditions of extraction of the proteins in the laboratory.

Sincerely,
Phil Lieberman, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology