Babies of mothers who followed a Mediterranean diet during pregnancy and ate fish regularly were less likely to suffer from colic and eczema at the same time. This is shown by a Harvard study of more than 1,300 mother–child pairs.
Infant colic and atopic eczema are among the most common worries of new parents. Whether diet during pregnancy plays a role was investigated by a team from the Harvard T.H. Chan School of Public Health and Boston Children’s Hospital. The results were published in JAMA Network Open on 12 October 2026.
Data from the long-term Project Viva study
Data from 1,324 mothers and their children from the US Project Viva cohort were analysed. During pregnancy, the women had completed questionnaires about their diet. From these, the researchers calculated two scores: how closely the diet followed the Mediterranean pattern and how pro-inflammatory it was.
Among the babies, around 12 per cent had eczema alone, around 21 per cent colic alone and just under 5 per cent both together.
Fish and a Mediterranean diet come out ahead
- The more Mediterranean the mother’s diet, the less often the child had colic and eczema at the same time: each additional point on the Mediterranean scale was associated with a 15 per cent lower probability.
- A pro-inflammatory diet, by contrast, was associated with a 34 per cent higher probability per point.
- Each weekly serving of fish or seafood was linked to an approximately 25 per cent lower probability.
- Dairy products, eggs and nuts showed no association.
For eczema alone, the study found no association with diet. The effects were most pronounced in mothers who themselves had allergies.
Editorial assessment
This is an observational study. It shows associations but does not prove that a change in diet prevents colic or eczema. In addition, the data date from 1999 to 2002. However, the results are consistent with general recommendations for a balanced diet in pregnancy with vegetables, whole grains, olive oil and fish. Pregnant women should choose low-mercury fish such as salmon, herring or trout and avoid raw fish.
Sources
- JAMA Network Open, 12.10.2026 – reported by News-Medical
- Dermatology Times, Journal Digest of 14.10.2026
