Yes, some food additives for sale can trigger allergic reactions or non-allergic hypersensitivity responses in susceptible individuals, though such cases are not universal—they only affect specific groups, and severity ranges from mild discomfort to life-threatening symptoms. Below is a detailed breakdown of the two main types of reactions and the common additives involved:

1. IgE-Mediated Allergic Reactions (Severe but Rare)
This is a classic immune response where the body produces immunoglobulin E (IgE) antibodies to target specific food additives for sale, treating them as "foreign invaders." Symptoms typically appear quickly (within minutes to hours of intake) and can be severe, even life-threatening in rare cases.  

Common additives linked to this type of allergy include:  
- Sulfites: Such as sodium metabisulfite, potassium bisulfite, and sulfur dioxide. They are widely used in dried fruits (e.g., raisins), wine, pickled foods, and processed meats to prevent oxidation and spoilage. About 5–10% of asthmatics are sensitive to sulfites, and exposure can trigger acute asthma attacks (wheezing, shortness of breath). In rare instances, they may cause anaphylaxis— a severe reaction characterized by facial swelling, difficulty breathing, and a drop in blood pressure, requiring emergency medical care.  
- Azodicarbonamide: A dough conditioner used to improve the texture of bread, cakes, and pastries. It is banned in the EU, Australia, and some Asian countries because it can break down into compounds that trigger allergic dermatitis (itchy, red, or blistering skin rashes) and respiratory allergies (runny nose, coughing, or tightness in the chest) in sensitive people.  
- Carmine: A red colorant derived from cochineal insects, often used in candies, beverages, and processed meats. It can cause IgE-mediated allergies in some individuals, leading to hives, swelling of the lips or tongue, and in rare cases, anaphylaxis. For this reason, many food labels now explicitly note "carmine (may contain allergens)" to alert consumers.  

2. Non-Allergic Hypersensitivity (More Common, Mild to Moderate)
Most "additive-related reactions" fall into this category—they are not driven by IgE antibodies but by other physiological responses, such as irritation of the digestive, nervous, or skin systems. Symptoms are usually milder than true allergies and may appear hours after intake, with less consistency across individuals.  

Common additives associated with non-allergic hypersensitivity include:  
- Monosodium Glutamate (MSG): A flavor enhancer used in instant noodles, restaurant dishes, and savory snacks. Some people report "MSG symptom complex" after consuming large amounts (typically ≥3 grams per meal, often on an empty stomach), with symptoms like headache, facial flushing, numbness around the mouth, and mild nausea. However, major regulatory bodies (e.g., the U.S. FDA, EU EFSA) have concluded that MSG is safe for most people, as these symptoms are not consistent in controlled studies and rarely occur with normal intake.  
- Artificial colors: Such as tartrazine (Yellow No.5), sunset yellow (Yellow No.6), and allura red (Red No.40), which are common in candies, soft drinks, and processed snacks. These colors are linked to "food dye sensitivity," which may cause skin rashes (e.g., hives), abdominal pain, or headaches in some individuals—especially children. The EU has even mandated warning labels for foods containing these colors, stating they "may have an adverse effect on activity and attention in children."  
- Benzoates (e.g., sodium benzoate): A preservative used in soft drinks, jams, and condiments. Rarely, it may trigger skin itching or hives in sensitive people, and this risk can increase when combined with artificial colors (a phenomenon called "additive synergism," where multiple additives amplify each other’s effects).  

Key Tips for Consumers
- Not all additives are allergenic: Most legally approved food additives for sale (e.g., citric acid, baking soda, vitamin C used as an antioxidant) have extremely low risk of causing reactions. Allergic or hypersensitive responses are limited to a small subset of additives.  
- Dosage is critical: Reactions usually occur only with excessive intake (e.g., drinking multiple cans of dyed soda in one day) or in highly sensitive individuals. Normal consumption of additive-containing foods rarely leads to issues.  
- Track potential triggers: If you suspect an additive is causing symptoms, keep a "food diary" to record what you eat and when symptoms appear. For persistent concerns, consult a doctor or allergist—they can help identify specific triggers through tests (e.g., skin prick tests for sulfites or carmine).  

In summary, while food additives for sale can cause allergic or hypersensitive reactions in some people, these cases are not common. With careful label reading, moderate intake, and awareness of personal sensitivities, most consumers can avoid potential risks.