Body Odor In Babies: What Is Normal And How To Deal With It

Image: Midjourney/ MomJunction Design Team

Body odor in babies is distinctive, and they may often smell of baby products or milk. However, babies who are not bathed on time or wear unclean clothes can have a sour or pungent odor. Most mothers could sense their babies smelling and try to keep them clean.

Some babies can even leave a cake or fruity odor. On the other side, some may smell rotten fish or cabbage. You may seek medical care to determine the causes of unusual body smell in babies. Read on to know the causes, treatments, and remedies for various body odors in babies.

In This Article

Key Pointers

Body odor in babies is often not a sign of a serious problem.
The odor is commonly caused by heat, dust, unhygienic surroundings, sweat, and urine.
Preventive strategies for managing baby body odor include regular bathing, applying moisturizers or baby powders, and keeping them clean and dry.
If a baby has an unusual smell such as fishy, fruity, or musky, they should be evaluated by a medical professional to rule out any underlying medical conditions.

Normal Types Of Body Odor In Babies

Lack of hygiene may lead to foul body odor in babies

Image: Shutterstock

The following body odors are very common among babies, and you need not worry about them.

1. Milky odor

Babies often smell of milk. The peculiar body odor fades away when your baby’s milk intake reduces, and they graduate to a solid diet. Maintaining a balanced diet and good hygiene can help manage any odors caused by dietary changes or sweat.

2. Sour odor

Sometimes, your baby might have a sour body odor when they are spitting up or when dirt and sweat are trapped in their underarms, neck area, or skin folds. The lack of proper hygiene can lead to irritation, redness of the skin, and bacterial or fungal infection in babies.

Quick fact

Babies smell pleasant to parents, and it activates reward pathways in the brain (9).

Common Causes Of Body Odor In Babies

Sweat, heat, and pollution may cause a foul body odor

Image: IStock

Some of the common causes of baby body odor may include:

Pollution and heat
Dust
Dietary imbalance
Dressing
Wet clothing
Unhygienic surroundings
Sweat
Urine MetabolicⁱA group of diseases that occur due to abnormal chemical reactions that affect how the body processes food disorders

Abnormal Types Of Body Odor In Babies

If your baby has a weird body odor, it may indicate an underlying health problem, such as a metabolic disorder. Some abnormal body odors in babies are the following.

1. Fish odor

Trimethylaminuria may cause a foul body odor in babies

Image: IStock

Babies with primary trimethylaminuria or fish odor syndrome (FOS) will have a rotten fish smell in their breath, urine, and sweat. This is a genetic disorder caused by an enzyme deficiency that prevents their body from breaking down trimethylamine (1).

Trimethylamine (TMA) is produced in the intestine when foods, such as eggs, legumes, some vegetables, fish, etc. are digested by colonic bacteria. TMA diffuses through the intestinal tract membrane and reaches the liver where it is metabolized into odorless trimethylamine oxide (TMAO).

Babies with hepatic diseases, such as viral hepatitisⁱLiver inflammation and damage caused by viral infections , may have rotting fish odor since TMA is not metabolized into TMAO in their liver. Kidney disorders may cause a fishy smell due to excessive bacterial growth in the intestine. Trimethylaminuria caused by hepatic or renal diseases is known as secondary trimethylaminuria (2).

2. Maple syrup odor

If your baby’s urine smells like maple syrup or cake, it can be because of maple syrup urine disease (MSUD). This is a rare genetic disorder due to the deficiency of an enzyme complex that breaks down certain amino acids (proteins) in the body. The accumulation of these amino acids and their toxic byproducts may give urine a distinct sweet smell. If left untreated, babies may develop neurological dysfunction and other neurological problems, such as seizures in babies (3).

Point to consider

Most signs of MSUD develop when the baby consumes food that their body cannot break down or has not eaten for a long time (10).

3. Musty odor

Phenylketonuria (PKU) is a congenital metabolic disorder that affects approximately 0.45 million individuals worldwide, as revealed by a study published in the American Journal of Human Genetics. This condition causes a musty odor to emanate from the body of affected babies. Babies with this genetic problem may have decreased metabolism of the amino acid called phenylalanine. If untreated, the accumulation of phenylalanine in the blood can lead to learning disabilities, behavioral problems, epilepsyⁱA central nervous system disorder characterized by unprovoked, recurrent seizures , lighter skin color, tremors, etc. (4)

4. Fruity odor

Fruity-smelling breath is one of the indicators of diabetes type 1ⁱA chronic illness characterized by increased sugar in blood due to a destruction of the pancreatic cells in babies. The fruity scent occurs due to diabetes ketoacidosis (DKA), a complication of diabetes type 1 due to the buildup of ketones in the body. If left untreated, diabetic ketoacidosis can be life-threatening in babies (5).

5. Cabbage odor

Babies with tyrosinemia type 1 may have a cabbage-like odor. This is a genetic metabolic disorder where an enzyme deficiency causes the accumulation of the amino acid tyrosine in the blood. If left untreated, this may cause developmental delay in children and other fatal problems, such as liver failure and enlargement of the spleen (6).

6. Sweaty feet odor

Isovaleric acidemia may cause a foul body odor in babies

Image: IStock

Isovaleric acidemia and glutaric acidemia type II are disorders causing a “sweaty feet” smell in babies. Although it is rare, you may have to distinguish these conditions from excessive sweating of the feet that itself results in the odor.

Isovaleric acidemia is a rare disorder caused by an inability to break down isovaleric acid. Its buildup results in sweaty feet odor and other symptoms, such as lethargy, failure to thrive, seizures, etc(7).

Glutaric acidemia type II (GA2) is an inherited disorder that interferes with the metabolism of fats and proteins in the body. This may result in sweaty feet odor in babies. The symptoms may vary depending on the severity of the disorder. GA2 could lead to lethargy, poor feeding, behavioral changes, and vomiting. The most severe form of the disorder is seen within the first four weeks after the birth, and the baby may have brain malformations, and heart and liver enlargement (8).

If you notice any of these or other strange smells, call your child’s doctor for advice. Keep in mind that most of these conditions are rare, and there could be another explanation for the smell. Unpleasant body odor due to poor hygiene alone can be dealt with improved personal hygiene.

How To Deal With Your Baby’s Body Odor?

Here are a few baby skin care steps you can take if your baby has body odor:

Bathe the baby using baby shampoos
Always pat dry and apply moisturizer after bath
Use baby powders to reduce sweating. Ensure that the baby doesn’t inhale any of the powder.
Use waterproof baby feeding aprons while feeding

Waterproof bibs may help prevent bad odor

Image: Shutterstock

Follow nursing hygiene and clean the baby’s face and neck after eating
Dress up your baby in light clothing during summer to avoid excess sweating
Always use clean and dry socks and shoes
Wash your baby’s clothes with a mild baby laundry detergent and dry them well
Change diapers on time
Use baby wipes or wash and pat dry the genital area while changing diapers

Frequently Asked Questions

1. What kind of soap should I bathe my baby with to prevent body odor?

The usual Baby soaps and washes are suitable for bathing your baby. Some antibacterial baby soaps are available, but using them under medical supervision is better. Do not use harsh and scented soaps and perfumed lotions to prevent body odor, as they may harm your baby’s delicate skin.

2. How often should I bathe my baby to prevent body odor?

Babies need not bathe every day, and two to three times per week is considered enough. However, you may bathe your baby daily with special attention to skin folds to prevent body odor (11).

3. Is it safe to use deodorant on my baby to prevent body odor?

Deodorants may contain chemicals that may not be suitable for your baby’s delicate skin.

4. At what age do babies develop sweat glands?

A board-certified pediatrician from Santa Rosa, California, Dr. Pierrette Mimi Poinsett, explains, “There are two kinds of sweat glands, eccrine and apocrine. Both develop while the baby is in the womb. Eccrine glands are all over the body and are functional soon after birth. Apocrine glands are functional with the onset of puberty from about eight to 13 years in girls and nine to 14 years in boys.”

Body odor in babies is a natural occurrence that disappears as they grow. But if your baby smells different from the distinctive milky or sour odor, it may be due to an underlying condition. Typical body odor in babies is generally due to their diet, sweat, or dressing. If your baby presents uncommon smells such as fishy odor or fruity odor, do not panic. Instead, you may try some effective hygiene practices for managing the odor. However, consult a doctor if the odor doesn’t disappear for early detection of any issue and timely treatment.

Infographic: Do Newborn Hygiene Practices Reduce Unpleasant Body Odors?

Babies usually have pleasant body odor. Babies’ unpleasant body odor, including foot odor, may indicate an underlying condition or poor hygiene practices. Go through the infographic to learn newborn hygiene measures to avoid unpleasant body odors.

newborn hygiene practices to avoid unpleasant body odors (infographic)

Illustration: How To Deal With Body Odor In Babies?

Image: Dall·E/MomJunction Design Team

References

MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.

1. Trimethylaminuria (“fish odour syndrome”); National Health Service, UK
2. Jeffrey Messenger, et al.; A Review of Trimethylaminuria: (Fish Odor Syndrome); The United States National Library of Medicine
3. Maple syrup urine disease (MSUD); The National Organization for Rare Disorders
4. Phenylketonuria (PKU); National Health Service, UK
5. Signs of Diabetes in Toddlers, Babies & Infants; Juvenile Diabetes Research Foundation
6. Tyrosinemia type I; The National Organization for Rare Disorders
7. Isovaleric acidemia; The United States National Library of Medicine
8. Glutaric acidemia type 2; The National Center for Advancing Translational Sciences
9. Ilona Croy, et al; 2017; Babies Smell Wonderful to Their Parents, Teenagers Do Not: an Exploratory Questionnaire Study on Children’s Age and Personal Odor Ratings in a Polish Sample; The United States National Library of Medicine
10. Maple Syrup Urine Disease; Baby’s First Test
11. Washing your baby; Pregnancy Birth and Baby

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Reviewer Expert Author Editor Fact Checker

Dr. Richard Mario LurshayMBBS, DNB

Dr. Richard Mario Lurshay has around 11 years of experience in the care of children and their well-being. After completing his post-graduation in Pediatrics, he completed his training in Pediatric Nutrition from Boston University School of Medicine (USA).

Read full bio of Dr. Richard Mario Lurshay

Dr. Pierrette Mimi PoinsettMD Dr. Pierrette Mimi Poinsett is a licensed pediatrician and a health advocate with 19 years of experience. She completed her doctor of medicine from the University of Chicago Pritzker School of Medicine and is currently practicing as a medical consultant in California.
Dr. Pierrette Mimi Poinsett is a licensed pediatrician and a health advocate with 19 years of experience. She completed her doctor of medicine from the University of Chicago Pritzker School of Medicine and is currently practicing as a medical consultant in California.

Dr Bisny T. JosephMedical Doctor

Dr. Bisny T. Joseph is a Georgian Board-certified physician. She has completed her professional graduate degree as a medical doctor from Tbilisi State Medical University, Georgia. She has around 5 years of experience in various sectors of medical affairs as a physician, medical reviewer, medical writer, health coach, and Q&A expert.

Read full bio of Dr Bisny T. Joseph

Rohit GarooBSc, MBA

Rohit Garoo is a writer-turned-editor with over 9 years of experience in content writing, editing, and content marketing. He did his bachelors in Science at St. Xavier's College, Hyderabad, and masters in Business Administration at Osmania University.

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Shinta Liz SunnyM.Tech

Shinta is a biotechnologist who is highly intrigued by science and technology. She holds a master's degree in Biotechnology from Karunya Institute of Technology and Sciences and a PG Diploma in cellular and molecular diagnostics from Manipal University.

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