As far as adult-onset food allergies, which are also increasing, shellfish are said to be most peculiar (or fishy, that is).
Prevalence and characteristics of adult-onset food allergy
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The 5 most common food allergies determined, in decreasing order of frequency, were shellfish (54%), tree nut (43%), non-shell fish (15%), soy (13%), and peanut (9%)...
The age of first reaction showed a wide range but peaked during the early 30s (mean, 31 years, range, 18-86 years)...
An older age at time of diagnosis is associated with higher risk for severe reactions...
In evaluating other characteristics of these patients, we observed a female versus male dominated bias (64% vs 36%), which contrasts with the male dominance described in pediatric food allergy.
Those who experience hay fever are more likely to develop a food allergy related to ingesting pollen actually.
Adult-onset food allergy
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The majority of patients with adult-onset food allergy suffer from the pollen-plant allergy syndromes. Many of them manifest their allergy after exercise and consuming food to which they are allergic. Eosinophilic esophagitis, an eosinophilic inflammation of the esophagus affecting individuals of all ages, recently emerged as another allergic manifestation, with both immediate and late response to the ingested food.
Oral allergy syndrome
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A 25-year-old man presents with itchiness in his mouth immediately after eating fruits such as apples, peaches and cherries. On a few occasions after eating peanuts and almonds, he also has felt tightness in his throat and a sensation that his throat was closing. He has a history of seasonal allergies (rhinorrhea and sneezing) in the early spring...
Most adult-onset food allergies are the result of cross-reactions between foods and inhaled allergens. Cross-reactivity is caused by IgE antibodies that can bind to pollen proteins and structurally similar food allergens (i.e., a pan-allergen)...
Our patient has symptoms caused by an allergy to raw apples, peaches and cherries. He should avoid these fruits; however, he may be able to eat them if they are cooked. A self-injected epinephrine device is not generally needed for oral allergy syndrome. However, because our patient presented with a feeling of tightness in his throat, such a device was prescribed.
Dust mites are said to cause a similar phenomenon (to pollen-plant syndromes) relative to shellfish allergies.
Shellfish and House Dust Mite Allergies
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The major allergen in shellfish allergy is tropomyosin, a pan-allergen that is also found in house dust mites and cockroaches...
Cross-reactivity between tropomyosins from house dust mites and shellfish has been well demonstrated.
Innate Immune Responses in House Dust Mite Allergy
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House dust mites (HDM; Dermatophagoides pteronyssinus) are one of the commonest sources of airborne allergens worldwide and we can consider that HDM sensitization affects more than 15–20% of the population from industrialized countries.
It is said that washing bed sheets (for example), in hot water, will help reduce the dust mites (along with cooler and less humid conditions indoors, etc). Likewise, the moist heat involved with boiling peanuts can help reduce their allergenicity, especially if they were not roasted already (which may do the opposite).
Effects of cooking methods on peanut allergenicity
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The methods of frying or boiling peanuts, as practiced in China, appear to reduce the allergenicity of peanuts compared with the method of dry roasting practiced widely in the United States. Roasting uses higher temperatures that apparently increase the allergenic property of peanut proteins and may help explain the difference in prevalence of peanut allergy observed in the 2 countries.
Frying would tend to be hotter than boiling, so it probably goes in order of boiling being best. I've tried boiling roasted peanuts too. They seem more digestable to me (as legumes, you know, it's like cooking beans—who roasts those... not me).