All over the world, particularly in developed nations, children are more likely to develop allergies than ever before.
Although most reactions are mild, the fact they can be fatal means patients and families have to live in fear and be constantly vigilant when purchasing food products in supermarkets and restaurants — but why are food allergies more common now?
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What Is an Allergic Reaction?
An allergy is a reaction our body has to substances called allergens when they come into contact with our skin, nose, eyes, respiratory tract, or gastrointestinal tract.
If you've ever experienced sudden and unexplained bouts of sneezing, a blocked nose, a red and itchy rash, or wheezing and coughing, it's likely you've had some sort of allergic reaction.
There's a good chance you have, because allergies are very common. In fact, more than 50 million Americans have experienced various types of allergies. Allergies are particularly common in children and, although some go away as we get older, many stay with the person for life. Adults will also sometimes develop an allergy to things they weren't previously allergic to.
Most allergic reactions are mild and no more than a nuisance, and can be controlled with medication, but severe reactions can be life-threatening.
What Are the Most Common Causes of Allergic Reactions?
In order to protect us from foreign substances and viruses, our immune system produces antibodies. However, when someone suffers from an allergy, their immune system makes antibodies to combat something that won't actually harm them. Our bodies mistake the allergen for something dangerous, even though it isn't.
People can be allergic to almost anything, but there are some substances more likely to trigger an allergic reaction. These include:
- Grass and tree pollen (you probably know this as hay fever)
- Certain foods, particularly nuts, fruit, shellfish, eggs, and dairy products
- Certain medicines, including ibuprofen, aspirin, and some antibiotics
- Mold
- Household chemicals, for example found in some detergents and hair dyes
- Dust mites
- Animal "dander" — tiny flecks of skin
Unlike symptoms of food sensitivity, which can take hours to present themselves after consuming the trigger food, allergic reactions usually happen within just a few minutes of exposure to an allergen.
The most common symptoms include:
- Sneezing
- A blocked or runny nose
- Red, itchy, and watery eyes
- Wheezing and coughing
- A red, itchy rash
- Worsened symptoms of asthma or eczema
The most dangerous allergic reaction is called anaphylaxis, or anaphylactic shock, and requires immediate medical attention.
Why Food Allergies Are More Common
According to the U.S. Centers for Disease Control and Prevention, the number of children suffering from food allergies increased by approximately 50% between 1997 and 2011. This increase has also been seen in other developed nations, with 7% of children in the UK and 9% in Australia now affected by food allergies.
There are a few theories on offer to explain why allergies are on the increase.
Are We Just More Aware of Allergies?
Are we just seeing increased rates of allergy diagnosis because we're more aware of them?
Allergy experts dismiss this as the cause, but there are issues in self-reporting. As many as 3–4 times as many people think they have a food allergy as actually do. One of the main reasons for this is confusion between food allergies and food intolerance.
Nevertheless, data from multiple studies shows a significant increase in worldwide allergies, up from 3% of the population in 1960 to approximately 7% in 2018.
The "Hygiene Hypothesis"
This isn't about us keeping our homes too clean — it's that, from a young age, our gut isn't encountering enough different types of microorganisms.
For example, modern homes are made with biocide-treated timber and plasterboard, and the "microbiota" — the organisms within a particular habitat — are now a long way from the environments we evolved from. Because we're encountering fewer of these microbes at an early age, our immune systems are less prepared and capable of responding to foreign substances. This is supported by studies that show the more antibiotics someone has as a child, the more likely they are to develop a food allergy.
Dual-Allergen Exposure Theory
Back in the 1990s, when food allergies started appearing, the guidance given to parents was not to give these foods to their children until they were three years old. Not only was this advice not based on evidence, it was actually the opposite of what parents should have been doing.
Just because an infant doesn't eat a peanut doesn't mean they won't be exposed to it. If a baby's first experience of peanuts is breathing it in through dust or via broken skin caused by a rash or eczema, they could be sensitized to it. This means the first time they eat a peanut, their immune system will perceive it as a threat and attack.
Rather than shielding children from these foods, parents should be introducing allergenic foods as early as possible. This is particularly true for children with eczema, as it's much easier for the substances to get into the body through broken skin.
Vitamin D Deficiency
Studies have also shown a link between the availability of sunlight and food allergies.
Research conducted in Australia found that children with a vitamin D deficiency were three times more likely to develop an egg allergy and 11 times more likely to develop a peanut allergy.
Vitamin D helps to regulate the immune system, which ensures the body is less sensitive to allergies. However, modern urban living with so much time spent indoors, coupled with parents following medical advice and always covering their children's skin with sunscreen, is leading to increased rates of vitamin D deficiency. In the US, this condition is thought to be twice as prevalent as it was just over ten years ago.
Getting Your Allergies Tested
Do you frequently experience uncomfortable symptoms after eating but aren't sure which part of your diet is causing it? Our Premium Allergy Test is designed to uncover how your body reacts to a wide range of food and environmental items, so you know what you need to avoid.
The test measures your IgE antibody levels against 174 food, drink, and environmental allergens, including grains, wheat, nuts, milk, meat, fish, fruit, and vegetables, delivering results within just five working days (upon receipt at our CLIA-certified testing lab).
With easy-to-follow instructions, free shipping, and a free return envelope to our lab, it couldn't be easier to discover if you suffer from a food allergy.
FAQs
Are food allergies actually more common, or are we just diagnosing them more?
The increase appears to be real, not just better detection — CDC data shows a genuine rise in confirmed pediatric food allergies, separate from the issue of self-reported allergies that turn out to be intolerances instead.
Can adults develop a food allergy later in life, even without a childhood history?
Yes — adult-onset food allergies are real and can develop to foods a person has eaten without issue for years, sometimes linked to factors like pollen cross-reactivity or changes in gut health.
Does introducing allergenic foods early actually reduce allergy risk?
Current guidance, informed by research like the LEAP study, supports early introduction of allergenic foods (including peanut) for most infants, a significant shift from the outdated "avoid until age three" advice — though parents of infants with eczema or an existing food allergy should discuss timing with a pediatrician first.
Understanding why food allergies are becoming more common can help put your own symptoms — or your child's — into context, and points toward genuine, evidence-based factors rather than simply "better awareness." If you're dealing with unexplained reactions after eating, testing is the clearest way to find out what's actually behind them.
