Diet Diversity And Food Allergy Prevention: A Parent’s Guide

USDA and AAAAI recommendations emphasize the importance of a diverse diet for babies starting solids. But what is a diverse diet, and could it help babies build up a tolerance to foods in the future? Here’s what parents need to know about a diverse diet for babies, based on the guidance.

Two recent sets of guidelines that focus on feeding babies both emphasize the importance of a diverse diet. Here's what you need to know:

USDA Recommendations from the Scientific Report

The USDA Scientific Report of the 2020 Dietary Guidelines Advisory Committee recognizes that feeding your baby a diverse, nutritious diet is key to developing healthy eating habits. Introducing a variety of healthy foods encourages babies to choose, eat and enjoy these foods as they grow, throughout the rest of their lives.

Every baby develops at a different rate, so every baby will have specific nutritional needs. But no matter how your baby is growing, following the USDA Scientific Report's recommendations will keep your baby’s diet diverse and nutritious.

What counts as a diverse diet, according to the USDA report? Here's an overview.

The USDA Scientific Report recommends these foods for babies 6-12 months who are starting solids:

  • Breastmilk or formula, to provide the needed nutrients while introducing solids
  • Fruits and vegetables---they should be prioritized. The best choices are fruits and vegetables high in vitamin A, vitamin C, and potassium. Feeding baby fruits and vegetables provides solid nutritional building blocks and encourages lifelong healthy eating habits.
  • Several different types of meats and seafood, as well as egg. This covers key nutrients, such as iron, zinc, choline, and healthy fatty acids.
  • Age-appropriate forms of peanut and egg, to provide healthy fatty acids and to help build up a tolerance to these foods
  • No added sugars
  • Very few added oils
  • Very few added solids and fats

The USDA Scientific Report recommends these foods for 12-24-month-olds, especially those no longer consuming breastmilk or formula:

  • Nutrient-rich foods that come from animals, including seafood, meat, poultry, dairy products, and eggs. (Seafood should be prioritized.)
  • Fruits and vegetables, especially high-potassium fruits and vegetables
  • Whole grains
  • Peanut, tree nuts, and seeds
  • No added sugar
  • Few oils

AAAAI Guidelines, A Diverse Diet, and Food Allergies

New guidance from three leading medical organizations, the American Academy of Allergy, Asthma, and Immunology (AAAAI); the American College of Allergy, Asthma, and Immunology (ACAAI); and the CSACI (Canadian Society of Allergy and Clinical Immunology), also recommends feeding babies a diverse diet.

As the guidance states, a diverse diet may help prevent babies from developing food allergies in the future.

Learn more about these early allergen introduction recommendations here:

In their guidance, the AAAAI, CSACI and ACAAI define diet diversity as “the number of different foods or food groups consumed over a given reference period.”

Key in this definition of a diverse diet are common allergy-causing foods: egg and peanut, plus cow’s milk, soy, wheat, tree nuts, sesame, fish, and shellfish, which are called “complementary” foods. The AAAAI guidance already recommends introducing peanut and egg around 4-6 months of life “to prevent peanut and/or egg allergy,” and “not [to] deliberately delay the introduction of [the] other potentially allergenic complementary foods,” because “there may be potential harm in delaying the introduction of these foods.”

But an even more diverse diet may be the next step in food allergy prevention: the more foods a baby is introduced to, the more foods they may build up a tolerance to later in life.

According to the AAAAI guidance: “Upon introducing complementary foods, infants should be fed a diverse diet, as this may help foster prevention of food allergy. There is observational evidence but not any [randomized controlled trials] supporting this recommendation, but this is balanced by no known harm in introducing a diverse range of foods. Future evidence may more conclusively demonstrate specific potential health benefits of diet diversity.”

The AAAAI classifies this diet diversity recommendation as “weak,” though, as there have only been a few trials with results that demonstrate diet diversity’s role in possibly reducing food allergy risk.

Also, as explained in the guidance, “Diet diversity studies to date have inherent limitations,

including [that] diversity is perhaps more important for typically allergenic than for nonallergenic foods, but [the existing] studies do not discriminate [between] the 2 aspects; [and that] diversity among and also within food groups, for example, how many fruits and vegetables, is not described.”

Still, the results that the current recommendation is based on look promising. Here’s an overview of some of the key findings that this diet diversity recommendation is based on.

The Roduit Study: Diverse Diet and Food Allergies

The AAAAI’s recommendation is largely based on a cohort study by Roduit et al., involving 856 children from several locations in Europe (Switzerland, France, Finland, Germany and Austria). This study was observational, though, not a randomized trial. The Roduit study investigated whether babies whose diets were more diverse were less likely to develop a food allergy later in life.

Here are some of the main findings from this study:

  • The less diverse a baby’s diet was in their first year of life, the greater their risk was of developing a confirmed food allergy in their first 6 years of life (based on babies who consumed 6 types of food vs. 0-5 types of food).
    • For every additional food that a baby ate, their food allergy risk was more greatly reduced.
    • But when reverse causality (the possibility that an allergy might have caused a less diverse diet) was accounted for, these results were no longer statistically significant.
  • Also, the less diverse a baby’s diet was in their first year of life, the greater their risk for sensitization to a food. (When a child is sensitized to a food, they are more likely to develop an allergy to that food in the future.)
    • So, the more diverse a baby’s diet was, the less likely they were to be “primed” to develop a food allergy.
    • Again, this was based on babies who consumed 6 types of food vs. 0-5 types of food.
    • These results were more statistically significant than the above results that examined confirmed food allergies.
    • Even when reverse causality was adjusted for, babies who consumed 6 foods were still significantly less likely to be sensitized to a food than those who consumed 0-3 foods.

Still, more studies on diet diversity and food allergies are needed, especially randomized controlled trials and studies that address the AAAAI’s current concerns.

In Conclusion

Feeding a diverse, healthy diet helps babies build nutritious eating habits for life, according to the USDA’s Scientific Report of the 2020 Dietary Guidelines Advisory Committee.

And as the new AAAAI/CSACI/ACAAI guidelines state, a diverse diet in baby’s first year may help prevent food allergies, based on the results of observational studies like Roduit’s. More information is needed to prove this conclusively, though, and to determine which foods may play a role in allergy prevention.

But for now, the USDA recommendations provide foundations for building a healthy and varied diet. Meanwhile, the AAAAI itself strongly recommends introducing peanut and egg to help babies tolerate these foods; recommends not to delay the introduction of other allergy-causing foods like milk, soy, wheat, tree nuts, fish and shellfish; and recommends introducing other diverse foods to your baby.


Jessica Huhn is content writer for Ready. Set. Food!

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All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

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