Low vitamins and minerals

Can my milk be low in vitamins or minerals?

Vitamin and mineral deficiencies are common around the world. Low levels may be caused by an unbalanced diet, disease, surgery, or medication. Sometimes, babies don’t get enough vitamins and minerals because there aren’t enough in their mothers’ breast milk. Babies may also be born with low levels and the breast milk cannot compensate. Many organizations recommend routine use of vitamin D for babies and all recommend babies get vitamin K at birth. Mothers should see their health-care providers if they think they or their babies are at risk.

A) Describing low vitamin and mineral levels

Occasionally, babies don’t get enough vitamins and minerals because there aren’t enough in their mothers’ breast milk. Babies may also be born with low levels and the breast milk cannot compensate.

Generally, a balanced diet and supplements taken by the mother during pregnancy prevent vitamin and mineral deficiencies. However, vitamin and mineral deficiencies are common around the world. For example, globally, an estimated 250 million children are vitamin A deficient and at risk of blindness and death (WHO 2020). One-third of the world’s population is iron deficient, another 1.8 billion people are thought to be zinc deficient, and 600 million are iodine deficient (Georgieff 2015). 

A deficiency in vitamins or minerals can be measured by a blood test. If you or your baby are at risk, please discuss this with your health-care providers.

Although taking very large doses of vitamins is usually not needed or recommended for the mother or the baby, there is little evidence that this is dangerous for the breastfeeding baby (Sauberan 2019).

B) Low vitamin levels

1) Vitamin B1 (thiamine)

Thiamine is also known as vitamin B1. It is found in whole grains, legumes, and some meats and fish. Mothers whose diet does not include these can develop thiamine deficiency. This can affect the nervous system and heart of both mother and baby (Bhat 2017; Nazir 2019).

2) Vitamin B12

Breast milk may be low in vitamin B12 if the mother’s vitamin B12 levels are low (Hasbaoui 2021; Kühne 1991; Sobczyńska-Malefora 2017). This may develop when a mother:

  • Has an unbalanced vegan diet (Kühne 1991).
  • Has a bowel disease (such as celiac or Crohn’s disease).
  • Had surgery in which part of the stomach or bowel was removed.
  • Is taking certain medications (such as acid-blocking medication).
  • Does not make enough of a helper molecule (intrinsic factor) to absorb B12.

Signs that a baby has low B12 levels include (Roumeliotis 2012):

  • Poor growth
  • Weakness and lack of energy
  • Poor muscle tone
  • Overactive reflexes
  • Delayed development
  • A small head
  • Abnormal irritability
  • Mouth sores
  • Vomiting

B-12 levels can be increased with oral or injected supplements. The choice will depend on the cause of the deficiency.

3) Vitamin D

Mothers and babies can be low in vitamin D. Many organizations recommend routine supplementation for the baby.

4) Vitamin K

Vitamin K does not cross the placenta well and is present only in low amounts in breast milk (Dror 2018a). Babies who have low levels of vitamin K are at risk of life-threatening bleeding during the first three months after birth.

To prevent this, babies are given vitamin K at birth. This can be done by injection or by mouth. Abnormal bleeding has been reported in babies given oral vitamin K but not in those who received an injection.

C) Low iron levels

1) Describing the role of iron

Iron is critical in the production of red blood cells which carry oxygen from the lungs to the body. Low iron levels can result in a lack of red blood cells (anemia). 

There are many causes of low levels of iron including a diet lacking in iron or when iron is lost through excess bleeding as with a difficult delivery. It is the most common nutritional deficiency in the world.

2) Low iron levels in the mother

Mothers with low iron levels may be very tired, making it hard for them to care for their babies. They may also:

  • Find they are frequently short of breath.
  • Feel their heart pounding.
  • Have headaches.
  • Feel dizzy or light-headed.
  • Feel cold.
  • Have a sore tongue.
  • Have nails that break easily.
  • Have a pale face, gums, insides of the lips or lower eyelids, or nails.
  • Have swelling and pain of the tongue and mouth.

Pregnant women with low iron levels are more likely to have premature or small babies.

Mothers who have low iron levels may: 

  • May have a reduced milk supply.
  • Have low iron levels in their milk.
  • Have babies with low iron levels.
  • Have small changes in other breast milk components (França 2013).  

3) Low iron levels in a baby

Some babies are at higher risk of being born with low iron levels or developing low levels after birth. These include babies who:

Signs that a baby has low iron levels include (Joo 2016):

  • Pale skin
  • Irritability
  • Tiredness
  • Weakness
  • Poor feeding
  • Poor growth
  • Poor long-term brain development and behaviour (Lozoff 2013)

4) Testing for iron levels

Iron levels are measured by a blood test. Recommendations on testing mothers and babies for iron and giving supplements vary (Brannon 2017).

Breastfeeding mothers who have normal blood iron levels do not need iron supplements.

Generally, organizations do not recommend routine testing of babies who are not at risk of low iron levels or are otherwise well nor giving healthy babies iron supplements.

5) Preventing and treating low iron levels in babies

Delaying the clamping of the umbilical cord can reduce the risk of low iron levels in the baby (WHO 2014).

Giving iron supplements to healthy babies appears to improve their blood tests, but the supplements may harm their immune function and long-term growth and health (Taylor 2018).

If iron supplements are given to babies, they are usually stopped once the babies are eating iron-rich foods.

D) Low zinc levels

1) Describing zinc deficiency

Zinc is an essential micronutrient and is found in every cell of the human body. It helps the body fight dangerous bacteria and viruses and is used to make protein and the genetic material in each cell (DNA).

2) Low zinc levels in the mother

Mothers can be zinc deficient if they:

  • Are vegetarians.
  • Are ill with bowel, liver, or kidney disease or diabetes.
  • Have sickle cell anemia.
  • Have a genetic inability to absorb or use zinc.

Mothers who are low in zinc may notice:

  • Weight loss
  • Loss of appetite
  • Wounds that do not heal
  • Skin changes that may look like acne, eczema, or blisters
  • Mental fogginess
  • Difficulty seeing at night
  • Decreased sense of smell and taste
  • Diarrhea
  • Hair loss or brittle hair
  • Frequent infections

3) Low zinc levels in the baby

Babies are born with some zinc stored in their bodies. Breast milk provides more zinc but in decreasing amounts. Starting solids around six months provides additional zinc.

Babies may have low amounts of zinc if they (Krebs 2014):

  • Had a mother who had low levels of zinc during or after the pregnancy (Dumrongwongsiri 2015).
  • Were born:
    • Premature.
    • Small.
  • Start solid foods after six months.
  • Do not get a lot of zinc in the foods they eat.
  • Have a genetic inability to absorb zinc.
  • Have chronic diarrhea or other diseases (including sickle cell anemia).

A very small number of mothers have very low levels of zinc in their breast milk because of a genetic abnormality. This prevents the cells involved in milk production from taking zinc from the mother's body and transporting it into her milk. This results in abnormally low levels of zinc in their babies (Chowanadisai 2006; Golan 2017; Itsumura 2016; McCormick 2014). This abnormality can also result in a low milk supply.

Signs that a baby has low zinc levels include:

  • Persistent skin rash, especially in the diaper area
  • Hair loss
  • Nail changes
  • Diarrhea
  • Loss of appetite
  • Poor growth
  • Irritability

4) Zinc treating and treatment 

Zinc levels are measured using a blood test. 

Healthy mothers and babies do not need zinc supplements. Zinc can be given by mouth to individuals who are deficient. 

E) Low iodine levels

1) Describing iodine

Iodine is a trace element that is essential to normal human growth and wellness. If someone does not get enough iodine, their thyroid cannot make enough thyroid hormones. Thyroid hormones control the rate of the body’s metabolism.

2) Sources of iodine

Iodine deficiency is more likely in areas away from oceans and in mountainous areas where the soil does not contain much iodine. Iodine deficiency has been documented in people with very restrictive diets such as vegans and in people who avoid salt that contains added iodine (iodinated or iodized salt) (Brooks 2014; Yeliosof 2018).

Iodine is routinely added to table salt to prevent iodine deficiency. Healthy mothers who have enough iodine in their diets produce milk that provides enough iodine to their babies (Dumrongwongsiri 2018). Mothers can take iodine supplements to increase iodine levels in breast milk (Dror 2018b). Iodine is often added to vitamins given to mothers before birth (Delshad 2019). Kelp and other forms of seaweed do not provide consistent levels of iodine.

Mothers should not large amounts of iodine, as this can cause low thyroid levels in the baby (Alexander 2017).

3) Signs of low thyroid hormones in adults

Low thyroid hormones in adults can cause:

  • Mental slowing
  • Weight gain
  • A low body temperature
  • A lack of energy

Low thyroid hormones in a breastfeeding mother can result in a low or reduced milk supply.

4) Signs of low thyroid hormone levels in the baby

Low levels of thyroid hormones in newborns can cause one or more of the following:

  • Excessive sleepiness
  • Poor muscle tone
  • Low body temperature
  • Jaundice
  • A hoarse cry
  • A large tongue
  • An umbilical hernia (This is a hole in the tissue under the skin of the belly button which allows the baby’s bowels to leave the belly and lie under the skin, creating a soft lump.)
  • Infrequent stooling (pooping)

In the long term, these babies can:

  • Have typical physical signs such as a thickened tongue, poor muscle tone, and a hoarse cry.
  • Grow slowly.
  • Have severe mental impairment.

5) Causes of low thyroid hormone levels in the baby

Newborns may be born with low levels of thyroid hormone. The most common cause of this globally is low levels of iodine.

Other causes of low thyroid hormones in babies include:

  • An absent or poorly developed thyroid gland
  • A genetic inability to make thyroid hormones
  • Exposure to large amounts of iodine in breast milk
  • The mother having genetic condition that lowers the amount of iodine in breast milk (Golan 2020)

6) Iodine testing and treatment

Blood tests can check for low levels of thyroid hormones and identify the cause. It is recommended that all newborns are tested right after birth using blood obtained from a heel prick.

Individuals can be given iodine or thyroid hormone by mouth.


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