Julie Hambleton
Julie Hambleton
April 17, 2023 ·  5 min read

Why your grandparents had fewer food allergies, but you don’t

Food allergies are rising, and it’s not just because we’ve gotten better at detecting and diagnosing them. Many of us are left baffled as to why our grandparents didn’t seem to have issues with allergies, while every year now, more and more children and adults are suffering from them. Theories abound on how and why food allergies have increased so dramatically over the last several decades—from how we live too cleanly to genetics and environmental factors. Scientists are still trying to understand why food allergies are rising to hopefully stop this acceleration.

Food Allergies Are On The Rise In Developed Countries

Food allergies are on the rise in developed countries, and there is no doubt. This is true for both children and adults. Some of these allergies are life-threatening, but most can be managed with proper care. The most common food allergens include peanuts, tree nuts, seafood (fish and shellfish), milk products (including lactose intolerance), eggs, soy, wheat, and corn. The question now remains: Why? There are several theories as to why this might be the case. (1)

Theory #1: We live too “clean”

It’s true that children in urban areas are more likely to have food allergies than their rural counterparts. The theory suggests that perhaps it is because their environment tends to be “cleaner” than that of children who grow up in more rural areas. Perhaps children who grow up in urban areas tend to spend less time outside and have fewer opportunities for exposure to microorganisms.

These children’s immune systems are, therefore, under-stimulated. For this reason, when they come into contact with the proteins from certain foods, the immune system interprets them as dangerous invaders. This leads to an exaggerated immune response, leading to an allergic reaction.

Theory #2: Genetics

Genetics certainly plays a role in whether or not you develop food allergies as an adult, but no evidence shows your chance of developing them is higher if your parents had them when they were growing up or not. Theories about genetics being linked with food allergies fall short because they don’t explain why so many people who never had food allergies develop them as adults. If genetics were the cause of food allergies, it’s unlikely that they would suddenly appear in a person who was never allergic to anything before.

Theory #3: We Are Deficient in Vitamin D

Vitamin D is a nutrient that most people don’t get enough of, and it’s essential for strong bones and overall health. A shortage of vitamin D has been linked with several conditions, including food allergies. The theory goes that if you have low levels of vitamin D in your system, you’ll be more susceptible to developing food allergies because your immune system won’t be as strong. This theory suggests that children and adults today receive less sunlight exposure, and therefore less vitamin D, because we spend so much less time outdoors. (2)

Read: Researchers find that brains with more vitamin D function better

Theory #4: The Previous Food Allergy Recommendations Were Wrong

Previously, because of a rise in food allergies in children, doctors recommended waiting until children were at least three years old before exposing them to common food allergens. But this advice has come under fire recently. The current recommendation is that children should be introduced to common allergens as soon as they are able to consume solid foods. There’s no evidence that delaying the introduction of these foods helps prevent allergies, and there’s some evidence that it may even increase the risk for developing food allergies. (3)

Theory #5: Environmental Factors


Your environment, or changes to your environment, can highly impact the development of allergies. For example, immigrants are more likely to develop allergies in their new country than in their original country. There are a number of theories about why this is. One theory suggests that immigrants may encounter new environmental factors, such as lifestyle habits and food additives, that make them more likely to develop allergies. Another theory states that the immunological systems of immigrants can change when exposed to new allergens for the first time in their lives.


Babies born via cesarean sections are also more likely to have certain allergies than vaginally birthed babies. A baby’s immune system is exposed to many different types of bacteria and other germs during the vaginal birth process. This exposure may help protect infants from developing allergies later on in life. Breastfeeding is also a factor allergy development. The longer a baby is breastfed, the less likely they are to develop allergies.

Read: The Health Benefits of Black Seed Oil


Pets are another key element. Research shows that children who grew up with pets are less likely to have allergies. The more pets you have, the less likely allergies are. The theory behind this is that children who are exposed to pets as babies develop more robust immune systems. It’s believed that these children also have lower rates of asthma and other respiratory conditions later on in life.

Pollutants, Chemicals, and Additives

It’s not just your home that can cause allergies. It’s also the chemicals and additives you come into contact with daily. Many people develop allergies because they have higher exposure to pollutants, chemicals, and additives than their parents did when they were young. This is in reference to air pollution, as well as food additives and the chemicals and hormones used in food production.

The Bottom Line

Scientists are still trying to pinpoint exactly why food allergies continue rising. The reality is that it is likely that all of these theories contribute somewhat. The best thing you can do to help prevent yourself or your children from developing one is to not fret and limit exposure to potential allergens and germs. Children need exposure early on in order to strengthen their immune systems.

Limiting your exposure to certain pollutants can be tough, depending on where you live. In your home, however, you can do your best to consume organic foods when possible and use natural products in the home. This will decrease your exposure to chemical additives and ingredients that might increase allergy development risk.

Keep Reading: Why Ezekiel Bread is the Healthiest Bread You Can Eat


  1. Why the world is becoming more allergic to food.” BBC. September 13, 2019.
  2. Why food allergies are on the rise.” BBC. Ralph Jones. October 25, 2020.