Diet changes for infant colic (2023)

Review question

Do colicky infants show an improvement when breastfeeding mothers follow a low-allergen diet, or when formula-fed infants are fed a special formula?

Background

Infantile colic is a common problem afflicting otherwise healthy infants in the first three months of life. It is characterised by episodes of inconsolable crying lasting for longer than three hours per day, for more than three days a week, for at least three weeks.

It can be very distressing for parents.

Dietary changes, such as removing cows' milk from a breastfeeding mother's diet or switching formula-fed babies to a special soy-based formula, might reduce the symptoms of colic.

Study characteristics

We found 15 randomised controlled trials, a type of study in which participants are randomly assigned to one of two or more treatment groups, involving a total of 1121 babies with colic. The evidence is current to July 2018.

Infants (balanced between boys and girls) were less than three months of age.

Key results

Most studies reported data on a combination of outcomes: duration of crying, number of responders in each group after treatment (i.e. those who experienced a decrease in daily crying), or frequency of crying episodes. We present these findings below. No study reported on parental or family quality of life, infant sleep or parental satisfaction. Six studies reported that there were no side effects as a result of the dietary changes.

Low-allergen diet

One study (90 infants) found that more breastfed infants responded to a low-allergen maternal diet than infants on a standard diet containing known potential allergens.

Another study (120 infants) found little difference in breastfed infants whose mothers were given a low-allergen diet (10/16, 62.5%) and formula-fed babies who were given soy milk (29/44, 65.9%), but the researchers did find that breastfed babies responded more to dicyclomine hydrochloride (a tablet for treating stomach spasms) than formula-fed babies.

Hydrolysed formula milk

One study (43 infants) found no clear difference in resolving symptoms of colic between the hydrolysed (hypoallergenic) and standard cow's milk groups. They also reported a greater reduction in crying time at study end in infants who were given hydrolysed, and reported no adverse effects.

A third study (21 infants) reported that infants whose parents were given information and support experienced a more rapid reduction in crying time than infants who were given a hydrolysed formula or dairy- and soy-free diet (within nine days).

A fourth study (267 infants) found that both partially hydrolysed formula with oligosaccharides (carbohydrates) and a standard formula with simethicone (a drug for treating symptoms of gas) reduced colic episodes after seven days, but effects were greater in the hydrolysed plus oligosaccharides group after two weeks. The study author confirmed there were no adverse effects.

Lactase enzyme supplementation

Three studies (138 infants) tested the effect of adding lactase (an enzyme which helps break down the lactose (sugar) in milk) to the infants' milk. There were no adverse effects in any of the studies.

Fennel, chamomile and lemon balm extract

One study (93 infants) found that average daily crying time in breastfed babies reduced within one week of treatment with a fennel, chamomile and lemon balm extract. There were no adverse effects.

Soy protein-based formula

One study (19 infants) found that, compared with cows' milk formula, soy formula reduced crying time and increased the number of responders. However, international guidance does not support the use of soy milk due to concerns that they can impact hormones in babies, so these results are not relevant.

Quality of the evidence

Many of the studies included only small numbers of participants and were of poor quality. We did not find evidence of effectiveness for most dietary interventions. Where studies did report some benefit, this was not large enough to be meaningful.

Conclusions

Based on the available evidence, we are not able to recommend any of the dietary modifications assessed in this review.

Infantile colic is typically defined as full-force crying for at least three hours per day, on at least three days per week, for at least three weeks. Colic appears to be more frequent in the first six weeks of life (prevalence range of 17% to 25%), depending on the specific location reported and definitions used, and usually resolves by three months. The aetiopathogenesis of infantile colic is unclear but most likely multifactorial. A number of psychological, behavioural and biological components (food hypersensitivity, allergy or both; gut microflora and dysmotility) are thought to contribute to it. The role of diet as a component in infantile colic remains controversial.

To assess the effects of dietary modifications for reducing colic in infants less than four months of age.

In July 2018 we searched CENTRAL, MEDLINE, Embase, 17 other databases and 2 trials registers. We also searched Google, checked references and contacted study authors.

Randomised controlled trials (RCTs) and quasi-RCTs evaluating the effects of dietary modifications, alone or in combination, for colicky infants younger than four months of age versus another intervention or placebo. We used specific definitions for colic, age of onset and the methods for performing the intervention. We defined 'modified diet' as any diet altered to include or exclude certain components.

We used standard Cochrane methodological procedures. Our primary outcome was duration of crying, and secondary outcomes were response to intervention, frequency of crying episodes, parental/family quality of life, infant sleep duration, parental satisfaction and adverse effects.