Vitamin D - healthy intake in first year linked to more muscle and less fat in toddlers

woman holding baby

A new study aimed at confirming the importance of vitamin D for bone density in babies and young children has also made an intriguing discovery regarding body composition. In addition to stronger bones, children who had a healthy intake of vitamin D during the first 12 months of life were also found to have increased muscle mass and less body fat at age three.

The findings, published in the journal Pediatric Obesity, are said to have come as a surprise for the research team. Dr Hope Weiler, Director of the Mary Emily Clinical Nutrition Research Unit at McGill University in Canada and one of the authors of the study, says: "We were very intrigued by the higher lean mass, the possibility that vitamin D can help infants to not only grow healthy skeletons but also healthy amounts of muscle and less fat."

The findings are said to be the first time such a connection has been made between achieving recommended vitamin D levels during a baby’s first 36 months and the development of muscle mass, but may reflect those of other studies that have found older children and adults may benefit from improved muscle mass and function as a result of increasing their vitamin D stores to a healthy level.

SACN advice

Experts at the Scientific Advisory Committee on Nutrition (SACN) issued advice to the UK public regarding vitamin D intake last year, which included a recommendation that everyone should consider taking a daily supplement. It is due to publish its final report on vitamin D and health shortly.

childs feet

Vitamin D and sun exposure

Natural synthesis of vitamin D via skin exposure to the sun coupled with a good diet was until recently considered adequate for most people, however, factors including indoor working, keeping skin covered, the use of sun screens to protect the skin from sun damage and Britain's often inclement weather are all factors that could leave many people with a deficiency, even during the summer months.

The National Institute for Health and Care Excellence (NICE) says that babies, children and those with fair skin - particularly those with freckles or moles and/or a family history of skin cancer - should take extra precautions when it comes to being out in the sun and the correct use of an appropriate factor sunscreen.

In addition, NICE says throughout the winter months in the UK (mid-October to early April) there is no ambient ultraviolet sunlight of the appropriate wavelength for adequate skin synthesis of vitamin D. NICE also published advice earlier this year to help people balance vitamin D requirements with minimising their risk of skin cancer. Check out our article, no safe way to tan says nice.

Contrary to popular belief, it is also not possible to produce enough vitamin D by sitting next to a closed sunny window, as vitamin D inducing UVB rays do not pass through glass, however, harmful UVA rays do pass through glass and can cause skin damage.

fruit and vitamins

Why is vitamin D so important?

Vitamin D is an essential nutrient for the maintenance of healthy bones, and is required to ensure optimum absorption of calcium and phosphorus from the diet. Deficiency can result in bones becoming soft and weakened, leading to bone deformities and osteomalacia or bone pain.

The vitamin is especially important for growing bones in children, where deficiency can cause rickets. According to NHS Choices, the vitamin is especially important for growing children, where deficiency can result in a condition called rickets. Rickets causes bone pain, poor growth and deformities of the skeleton, including bowed legs, curvature of the spine and thickening of the ankles, wrists and knees. Children with rickets are also more susceptible to bone fractures.

A common ailment in the past, rickets had mostly disappeared in the Western world as a result of improved diet, however the NHS says there has been an increase in recent years - 900 cases were diagnosed in England in 2012.

Vitamin D is added to some breakfast cereals, margarine spreads and infant formula milk and can also be sourced naturally in foods such as eggs, meat and oily fish, however, experts say these amounts are small and not sufficient to prevent deficiency.

pregnant woman

The NHS currently recommends that people in the following at-risk groups take a daily vitamin D supplement:

  • Pregnant and breastfeeding women
  • Babies and children aged between six months and five years
  • Adults over the age of 65
  • People with darker skins of African, Afro-Caribbean and South-Asian origin
  • Anyone else who spends very little time outdoors during daylight hours, such as night workers and the housebound.

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Georgie Fenn, writes most of our news articles and social media posts.