What Is Colic? Symptoms, Causes & How to Help Your Baby

Understanding Colic: The Rule of Threes

Pediatricians use the "rule of threes" — first described by Dr. Morris Wessel in 1954 — to diagnose colic: crying that lasts more than 3 hours per day, more than 3 days per week, for more than 3 weeks in an otherwise healthy, well-fed infant. It is one of the most common concerns that bring new parents to their pediatrician in the first two months of life, affecting roughly 10–25% of infants globally.

What separates colic from ordinary newborn fussiness is its relentless quality. The crying often starts suddenly, typically in the late afternoon or evening, and resists all normal soothing attempts. The baby may clench their fists, pull their legs toward their abdomen, arch their back, and turn red in the face. Despite looking intensely distressed, a colicky baby is otherwise healthy — feeding well, gaining weight appropriately, and showing no signs of illness between episodes.

It is important to note that colic is a diagnosis of exclusion. Before attributing crying to colic, a healthcare provider should rule out other treatable causes such as ear infections, urinary tract infections, corneal abrasions, hair tourniquets, or feeding difficulties. If your baby develops a fever, refuses to feed, vomits forcefully, or the crying pattern changes suddenly, always seek medical advice promptly.

What Causes Colic? (It Is Still Debated)

Despite decades of research, no single definitive cause of colic has been identified. The leading theories span multiple body systems:

• Gut microbiome imbalance: Studies have found that colicky babies tend to have lower levels of beneficial Lactobacillus bacteria and higher levels of gas-producing Proteobacteria in their intestines. This may contribute to increased gas production and intestinal discomfort. Some trials of the probiotic Lactobacillus reuteri have shown a reduction in daily crying time in breastfed colicky infants, though evidence is still emerging.
• Immature digestive system: The newborn gut is still developing the coordinated muscle contractions needed for efficient digestion. Irregular peristalsis can cause gas to become trapped, leading to temporary discomfort and crying.
• Overstimulation and neurological immaturity: Some researchers believe colic reflects a developmental phase where the infant brain is not yet efficient at filtering and processing sensory input. As the nervous system matures, the ability to self-regulate improves — which may explain why colic reliably resolves by 3–4 months.
• Food sensitivities: In a subset of colicky infants, sensitivity to cow's milk protein (either in formula or passed through breast milk) may play a role. Breastfeeding mothers who eliminate dairy from their diet sometimes notice an improvement, though this is not universally effective.
• Swallowed air: Babies who feed rapidly, have a poor latch during breastfeeding, or are fed from a bottle with a fast-flow nipple may swallow excess air, contributing to gas and discomfort.

How to Soothe a Colicky Baby

There is no universal cure for colic, but many families find that a combination of the following strategies helps reduce the duration and intensity of crying episodes:

• Rhythmic motion: Gentle rocking, swaying, bouncing on a yoga ball, or a short car ride can trigger the calming reflex in young infants. The key is rhythm — steady, predictable movement is more effective than irregular jostling.
• White noise: Loud, continuous white noise (louder than you might expect — roughly the volume of a running shower) mimics the whooshing sounds of the womb. Dedicated white noise machines, fan sounds, or apps can be very effective.
• Swaddling: Wrapping your baby snugly in a swaddle blanket reduces the startle reflex and can help a distressed baby feel more contained and secure.
• Tummy massage: Gentle clockwise circular strokes on your baby's abdomen can help move trapped gas along the intestines. Always do this when your baby is calm enough to tolerate it.
• Burping frequently: Burp your baby partway through feeds and at the end of each feed. Try different burping positions — over the shoulder, sitting upright on your lap, or face-down across your lap — to find what works best.
• Skin-to-skin contact: Holding your baby against your bare chest regulates their temperature, heart rate, and stress hormones, and can have a calming effect during fussy periods.

Colic is exhausting for parents. It is completely normal to feel overwhelmed, frustrated, or even resentful during prolonged crying episodes. If you feel yourself reaching a breaking point, place your baby safely in their crib on their back and take a few minutes to decompress. Never shake a baby. Reaching out to your partner, a family member, or your healthcare provider for support is a sign of strength, not failure.

Frequently Asked Questions