If your baby is often tense, cries furiously for hours on end in the evenings and is unable to be soothed, you might have been told its “colic”. Finding an effective solution for your baby’s distress relies on pinpointing the cause. Learn what colic is and what its not, and the different theories on cause.
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What is infant colic?
Infant colic is not a specific condition rather a term used to describe "excessively long periods of inconsolable crying in a healthy, thriving baby". In other words 'infant colic' describes how a baby behaves rather than what a baby has. When a health professional makes a diagnosis of 'colic', he/she is really saying, "Your baby is healthy and I can see no obvious reason for her crying".
Around 20% of healthy newborn babies' crying pattern fits the criteria for 'colic'. Breastfed and formula fed babies are affected equally. Long periods of inconsolable crying typically occur between the ages of 2 and 16 weeks, with the peak period of irritability occurring around 6 to 8 weeks.
Although it can be frightening, long periods of inconsolable crying displayed by a physically well, thriving newborn baby is not dangerous. The crying will cause no serious problems for your baby.
Signs and symptoms
The main symptom of infant colic is nonstop crying that lasts 3 hours or more. Crying episodes can occur at any time, day or night, but more commonly occur in the evenings between the hours of 6pm and 11pm. Nothing parents do, soothes their baby or stops the crying.
The baby is physically well and gaining good weight. During a medical examination there are no physical signs that point to a physical problem. [If there are physical signs - it's not colic.] In addition to crying, the baby might display behavior that indicates distress; such as facial grimacing, refusing feeds, clawing her face, flailing arm and leg movements, and pulling up her knees.
The medical criteria for a diagnosis of 'colic' is inconsolable crying for 3 or more hours, 3 or more days per week, for more than 3 weeks. However, many health professionals and people in general tend to blame 'colic' for any unexplained crying (inconsolable or otherwise) displayed by healthy newborn babies, and to a lesser extent, older babies.
The distress displayed during crying episodes is typically attributed to gastrointestinal discomfort or pain; possibly because this is one part of the baby's body that cannot be seen, or because of the common misperception that drawing up of knees provides evidence of abdominal pain. [Newborn babies draw up their knees into a fetal position when crying - for any reason.] There are numerous reasons why a healthy newborn baby might cry nonstop and display distressed behavior; most have nothing to do with gastrointestinal discomfort/pain.
What causes infant colic?
No matter who you talk to, everyone will have a different opinion about the cause, and the best way to treat infant colic. Not even the experts agree as to why 20% of healthy newborn babies cry inconsolably for hours on end.
There are numerous theories on the cause; as yet none have been proven. Its likely that the distress displayed by so-called 'colicky' babies is not due to a single cause, but rather involves a combination of different causes, and that the combination that could differ for individual babies.
Some theories on the cause of infant colic put forward over the years include:
1. Swallowed air
This theory suggests that infant colic is due to pain caused by air swallowed during feeding. The air then passes into the baby's intestinal tract where it is suspected that it either becomes trapped and causes discomfort owing to bloating, or that it causes painful abdominal spasms or cramps.
Swallowed air is widely claimed to be the cause of infant colic. However, there is no evidence to support this theory. In fact, the evidence contradicts this. Studies that compared the amount of air in babies' intestinal tracts showed no correlation between intestinal gas and crying. (See Infant gas for more information.)
- Air cannot does not become 'trapped' in a baby's intestinal tract. Swallowed air will either be burped up or enter into the intestines where it will be pushed through and passed as flatus (farts).
- Failure to burp a baby does not cause infant colic.
- Taking a baby outside on a windy day or driving with the car window open does not cause a baby to swallow air.
2. Baby's diet
A baby's diet is often suspected of causing colic. It is possible for babies to experience distress owing to gastrointestinal (GI) discomfort related to digestive disorders; however, there will be clearly observable physical signs that point to these conditions.
Milk protein allergy
Milk protein allergy is thought to affect 2% of formula-fed babies and to a far lesser extent, exclusively breastfed babies. Cows' milk protein is the most common cause of milk protein allergy (because its the most common milk source used in infant formula); however, goats' milk and soy can also cause allergic reactions in susceptible babies. Milk allergy generally affects the GI tract, respiratory tract and skin. Symptoms include; excessive gassiness, cramps, vomiting, diarrhea, coughing, wheezing, nasal congestion, rashes, hives and eczema. Milk protein allergy will cause a formula-fed baby to gain poor weight or lose weight (as vomiting and diarrhea are ways in which the baby's body will attempt to flush out allergens); whereas a breastfed baby who is only occasionally exposed to a milk protein allergen through her mother's diet might struggle to gain sufficient weight.
Milk protein intolerance
Milk protein intolerance is not the same as milk protein allergy. Symptoms linked to milk protein intolerance tend to be confined to the GI tract. These include; excessive gassiness, cramps and diarrhea. A formula-fed newborn baby will lose weight owing to her inability to adequately digest (and therefore absorb) the protein contained within her only source of nutrition.
Lactose intolerance is a condition that makes it difficult to digest lactose (the main carbohydrate found in milk). Because this is a relatively common problem experienced by adolescents and adults, it's one of the first conditions parents worry about when faced with a distressed baby. However, it's rare for babies and young children to suffer from lactose intolerance (except during and for a short while after a bout of gastroenteritis). GI symptoms include: excessive gassiness, cramps, and watery diarrhea caused by the fermentation of undigested lactose in the large bowel. As milk is the only source of nutrition and fluid for newborn babies, those suffering from lactose intolerance - and hence unable to adequately digest lactose - will be deprived of one of their main sources of energy (calories). They lose weight, become dehydrated as a result of chronic diarrhea, and quickly become extremely unwell.
Countless numbers of healthy, thriving babies are misdiagnosed with lactose intolerance and/or milk protein allergy or intolerance when the cause of their GI symptoms is due to lactose overload.
Lactose overload (also known as functional lactase insufficiency) is not a medical condition but rather a natural phenomenon that affects around two thirds of healthy breastfed babies and innumerable formula-fed babies in the early months of life. The GI symptoms associated with lactose overload are identical to lactose intolerance. However, unlike babies with lactose intolerance who lose weight, babies troubled by lactose overload gain average or large amounts of weight.
Some people mistakenly blame dietary iron for infant gas and/or constipation. However, the amount of iron in breast milk or iron-fortified formula is not enough to cause stomach ache. Iron is essential for growing babies. NEVER try to restrict iron in your baby's diet unless advised to do so by your baby's doctor.
3. Breastfeeding mother's diet
Foods eaten by nursing mothers are often blamed, but rarely the reason for infant colic.
Gas producing foods
This theory suggests that gas-producing foods such as cabbage, cauliflower, broccoli and onions, in the mother's diet will cause excessive intestinal gassiness and discomfort for her breastfed baby. Studies suggest that this is unlikely.
Sodas (soft drinks)
Nursing mothers are often told that if they drink sodas that contain carbonate (which make the bubbles) that this will cause excessive gas in the intestinal tract of their breastfed babies. This theory has not been proven to be a cause of infant colic. (However, it is wise for nursing mothers to drink plenty of water and restrict sodas.)
Another theory relating to a mother's diet is that too much coffee, tea, chocolate or sodas containing caffeine (such as colas, Mountain Dew and energy drinks) can cause infant colic. Caffeine is easily transferred in breast milk and when consumed in large amounts by nursing mothers has been shown to cause agitation and irritability in babies. If you limit coffee to 3 cups or less per day (or an equivalent amount of caffeine from other sources) the amount of caffeine transferred in your breastmilk is unlikely to cause a problem for your baby.
Although rare, it is possible for a breastfed baby to develop an allergic reaction to a food substance eaten by her mother. This includes milk but also other foods. A reaction to food allergens in breastmilk will initially cause increased fussiness or crying. However, babies with a food allergy will usually develop allergic symptoms like coughing, wheezing, sneezing, rashes or eczema within a few days or weeks. (See milk allergy & intolerance for more information.)
4. Gastro-intestinal problems
Spitting up milk is normal for babies. Up to 70% of all babies under the age of 4 months spit up occasionally or regularly. This can vary from frequent tiny amounts to large vomits that seem like the entire feed. Regurgitation (reflux) of stomach contents is often blamed but rarely responsible for long periods of inconsolable crying displayed by healthy, thriving babies.
Only a tiny percentage of babies experience distress as a result of the regurgitation of stomach contents. Some throw up so much milk that they can't keep enough down to sustain healthy growth, and consequently they become distressed owing to hunger. Others experience heartburn as a result of repeated regurgitation of stomach acid into the esophagus (food tube). This can cause inflammation or ulceration of the baby's esophagus. Swallowing then becomes painful and the baby fusses or refuses to eat, and as a result gains weight poorly or loses weight. The baby becomes distressed owing to pain and hunger, and cries inconsolably for hours at random times during the day and night.
[See our article on reflux to tell the difference between what's normal and what's not.]
When a baby abruptly pulls away from the breast or bottle, fidgets, grunts, passes some gas or poops and then returns to feeding, this is due to the gastro-colic reflex. This is normal infant behavior! Feeding stimulates the gastro-colic reflex, which causes wave-like contractions in the intestinal wall and pushes food and waste along the intestinal tract. It is not painful, but the baby is aware of the sensation. In response, the baby demonstrates behavior that appears like she wants to poop or pass gas, but sometimes she may only bear down. When nothing is passed it can appear like a baby is straining owing to constipation. (See infant reflexes for more information.)
Another theory on the cause of infant colic is that the baby's distress occurs as a result of an exaggerated gastro-colic reflex action, which causes intense, painful spasms of the intestinal wall. It is believed that these spasms can continue for hours, during which time the baby is distressed. The baby's pain is believed to be relieved when she poops or passes gas.
Constipation is often blamed for a baby's distressed behavior. However, constipation is not a reason for infant colic (as colic occurs at predictable times in the evenings, for weeks on end). Constipated stools are hard, dry and pebbly. Treatment of constipation will relieve any discomfort. (See our article on constipation for more.)
The gastro-colic reflex can trigger behaviour that is often mistaken as straining due to constipation; such as drawing up legs, grunting, groaning, going red in the face. The difference is baby passes normal stools.
Immature digestive system
Many people believe that immaturity of newborn babies' digestive system is the reason some babies suffer from gastrointestinal discomfort. A baby's digestive system does not produce sufficient quantities of digestive enzymes needed for breaking down foods other than breast milk or infant formula until around 4 months of age. However, if an immature digestive system was the cause of infant colic, then 100% of newborn babies would become distressed because they all have immature digestive systems.
For years it was thought that infant colic was a result of a baby's stress from being handled and cared for by inexperienced parents. However, some dismiss this cause because first born babies do not cry any more than later born babies, which would be expected if parental inexperience was the cause.
We don't know what we don't know! Unless a parent is an expert in child development, infant feeding and settling methods, there are usually things that even experienced parents can learn about the care of babies. In the case of physically well babies, often all that is required to promote their contentment is for parents to gain increased accuracy in interpreting infant behavioral cues and/or make appropriate adjustments to their infant feeding or settling practices.
6. Baby's temperament
Some health professionals believe that prolonged periods of crying is merely an extension of crying that is normal for all babies under the age of 4 months. The far end of the spectrum, so to speak. The theory is that a baby's temperament (inborn personality traits) is the reason some babies cry louder and longer compared to others.
While some babies may indeed cry more intensely or longer than others owing to their temperament, I don't believe it's 'normal' for any baby to cry inconsolably for hours on end.
7. Neurological development
It has been observed that babies who experience long periods of inconsolable crying are more sensitive to sensory stimulation compared to other babies. As a result, they can easily become distressed owing to over-stimulation (a problem where the baby becomes overwhelmed by sensory stimulation). Some health professional suggest that 'colic' has nothing to do with stomach pain at all, but instead is due to the baby's inability to block out unwanted sensory stimulation and/or regain a state of calmness when overstimulated. Once worked up, many babies, particularly those under 3 months, can have a hard time calming down.
8. Sleep deprivation
Others believe the distressed behavior displayed by 'colicky' babies is as a result of chronic sleep deprivation rather than pain due to a physical problem. The distress displayed by sleep-deprived babies, which is typically worse in the evenings, can be easily mistaken as pain and/or colic. An overtired baby will find it difficult to fall asleep owing to stress hormones circulating in their blood stream [caused by sleep deprivation] but will eventually fall asleep owing to physical exhaustion.
This theory is based on the belief that a baby's learned dependence on a parent's help to fall asleep or unreliable props or aids like a pacifier, can cause broken sleep if the parent removes their help or the pacifier falls out while the baby is sleeping. Learned dependence on outside help or on props to fall asleep generally means the baby is reliant on the same help to move from one sleep cycle to the next and remain asleep long enough to feel refreshed. If the parent removes their help or the pacifier falls out before baby has had sufficient sleep, the baby is at increased risk of waking prematurely, still tired. This can cause a sleep debt. If repeated, the baby's sleep debt will build over the course of the day, and consequently so will her distress. (See our article on sleep associations.)
9. Spinal functional disturbance
Chiropractors believe that infant colic may be linked to a minor misalignment of vertebra in the baby's spine, which can arise from the physical stress a baby's body endures during birth. Minor displacement of vertebra at the base of a baby's skull can place pressure on the vagus nerve. The vagus nerve is responsible for proper functioning of the entire GI tract. Pressure on the vagus nerve can cause hypertonia or hypotonia of nerve impulses, and this can lead to varying types of dysfunction within a baby's GI tract. A chiropractor will apply slight pressure to correct the baby's spinal alignment and thereby release the vagus nerve.
Osteopaths believe infant colic may be due to compression at the base of the skull, which can in turn affect the spine and pelvis. In the treatment of colic, osteopaths use gentle rhythmic movement of the head called 'cranio-sacral therapy' to release pressure the vagus nerve.
10. Other conditions
There are also a number of other conditions that affect babies which are at times blamed for long period of inconsolable crying by healthy babies.
An overgrowth of the yeast fungus called 'Candida Albicans' can cause a thrush infection in a baby's mouth. Sometimes a 'sore mouth' is blamed for a baby's inconsolable crying or feeding difficulties. However, even if a thrush infection remained untreated, it is very rare for it to reach the level where it will cause distress for a baby (i.e. ulcerations in the mouth).
Parents often start to worry about the possibility of 'sore gums' due to teething when there is no obvious reason for their baby's distress. Teething does not cause distress in the newborn period (birth to 3 months). Apart from the rare occurrence where babies are born with a tooth, it is unusual for the first tooth to appear before the age of 3.5 months, a time when long periods of nonstop crying in the evenings generally disappear.
Understandably, a severe diaper rash could cause discomfort for a baby, and she may cry periodically due to the stinging or burning effects of urine (pee) or stools (poop) on tender raw skin.
There is a booming industry supported by 'infant colic'. A quick search on the Internet will reveal numerous different types of lotions, potions, remedies and contraptions, all of which promise to cure infant colic.
Unexplained crying is one of the most common reasons why parents seek medical advice. Doctors are often at a loss to do anything other than recommend dietary changes, anti-colic medications, or reassure parents that baby is well and will outgrow long periods of inconsolable crying by around 3 months of age. Each of these strategies offers varying degrees of success. Some do nothing, some placate the baby in the short-term, some relieve GI discomfort associated with lactose overload or milk allergy or intolerance, and others simply sedate the baby. Other health professionals may advise parents on soothing methods aimed at relieving intestinal gas; like repeated burping during feeds, warm baths, or tummy massage.
A major flaw associated with using anti-colic medications and soothing methods is that even when these strategies are effective - which they often aren't - they aim to soothe an already distressed baby. They seldom do anything to remedy the underlying cause. Once the medication has warn off, the baby's distress returns, and at best soothing methods offer only temporary relief. In some cases dietary changes can 'cure' a baby's distress but cause problems for the baby further down the tract. For example, a misdiagnosis of lactose intolerance or milk protein allergy or intolerance may result in a breastfeed baby being switched to lactose-free formula (hypoallergenic formulas are also lactose-free), when in reality the baby's GI symptoms may have been due to lactose overload. Lactose-free formula will relieve GI discomfort associated with lactose overload, but it is completely unnecessary. Making minor but appropriate adjustments to a nursing mother's breastfeeding practices is generally all that is required to effectively relieve her baby's GI discomfort in less than 24 hours. Needless dietary changes may then deprive a breastfed baby of the many benefits that breastfeeding offers.
Preventing a baby's distress is obviously going to be far more effective than trying to soothe her once she has become distressed. Recognition of the cause is an essential step towards prevention. Accurate identification of cause of a physical well baby's distress is not something that can be achieved during a brief consultation. And it's definitely not something that can be achieved without a thorough assessment of the parent's infant feeding and setting practices.
When to see a doctor
If you don't know the cause of your baby's distress then it's wise to have her examined by a medical physician. Although long periods of nonstop crying display by physically well, thriving babies is rarely due to a medical problem/condition, its is important that she is examined to rule out any underlying physical or medical cause.
But remember, in the case of infant colic, there are no visible signs that point to a physical problem. So don't limit yourself to searching for a medical cure to a problem that might not have a physical or medical cause.
What to do when at the end of your rope!
It's natural to feel anxious and upset when your baby cries. Firstly, it's important to accept that all babies cry. Secondly, crying will not harm her.
If another adult is available to take over the care of your baby, give yourself a break. Attend to your physical needs and try to relax. Take a walk, soak in the bath, or anything else you find works to reduce your stress levels.
If you need a break to attend to your physical needs or to soothe your nerves but have no other adult available to care for baby, its okay to put her into the safety of her crib. Have something to eat and drink, or take a shower; whatever you need to do to feel comfortable. If you are still feeling tense, call a friend or family member and ask them to come over. If they can't come over, talk to them over the telephone until you feel calmer.
NEVER SHAKE YOUR BABY! This can cause serious and permanent brain injury or death. Many babies are unintentionally killed in this way every year.
Written by Rowena Bennett.
© Copyright www.babycareadvice.com 2004. All rights reserved. Permission from author must be obtained to copy or reproduce any part of this article.
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A consultation with one of our qualified and experienced consultants can help you to pinpoint the reason or reasons (as is often the case) for your baby's distress. We can explain how a baby's needs change in harmony with development; how to increase your accuracy in interpreting your baby's behavioural cues; and advise you on infant feeding and settling strategies to promote your baby's contentment.
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