Research suggests that up to 40 percent of all infants have colic. Yes, that’s a big number, so knowing that you’re not alone should be a little comforting. Additional comfort: Doctors and researchers are discovering more about what might cause colic, how it affects babies, and what you can do to get through it.

What Causes Colic? Tackling the Big Question

What causes babies’ crying, fussiness, and colic? Doctors and researchers have a number of possible reasons:

  • A common belief is that baby’s colic, crying, or fussiness might be related to baby’s digestive system. Food either moves too quickly through the system or food is not fully digested. You could try switching formulas to see if that helps.
  • Research suggests that infants with parents who smoke may be at increased risk of colic.
  • Mothers who had a history of migraines were more than twice as likely to have babies who suffered from colic than mothers who didn’t have migraines. Reducing stimulation for your baby—turning off lights, blocking out loud noises—might help.
  • In some cases, persistent colic may be related to a cow’s milk allergy. You can read more about this and other allergy-related concerns in our Cow's Milk Allergy Center. If there are accompanying issues like diarrhea, vomiting, or a skin rash, follow up with your baby’s doctor.
  • Some experts think colic is a normal, temperamental personality trait and it just takes certain babies a little bit longer to adjust to life outside the womb.

Excessive Crying May Be Temporary

What researchers agree on: Babies may eventually outgrow colic, crying, and fussiness. Colic:

  • Usually starts when a baby is 3 to 6 weeks old
  • Often ends when a baby is 3 to 4 months old

So remember that colic may be only a phase. In the meantime, try these tips to soothe your baby:

  • Make sure he’s not too hot or too cold.
  • Make sure he’s not hungry; if he’s not, don’t over-feed him.
  • Burp him often.
  • Rub his back and take him for a walk.

To Learn More

For even more helpful advice, read “Coping with a Crying or Colicky Baby: Everyday Tips.”