Mom’s Sunshine Vitamin Leads to Mightier Muscles in Kids

Muscle strength is something we all need, not just for athletic performance, but for everyday tasks like carrying groceries, lifting a child, or simply maintaining balance. And it turns out that one vital nutrient is key to keeping our muscles strong: vitamin D.

Vitamin D: Essential for Muscle Strength and Much More

Often called the “sunshine vitamin” since the primary way we obtain it is through exposure to sunlight, vitamin D is necessary for maintaining strong bones, a healthy immune system, and even supports mental wellbeing.

While most people are aware that vitamin D is essential for bone health, research has also shown that it plays a significant role in maintaining and improving muscle strength and function. This is vital not just for adults, but also for children – and it starts as early as pregnancy.

A Strong Start for Children Begins with Mom

A groundbreaking study conducted at the Medical Research Council Lifecourse Epidemiology Unit (MRC LEU) at the University of Southampton discovered that higher vitamin D levels in pregnant mothers can lead to children with stronger muscles.

Researchers examined more than 670 mothers in the later stages of pregnancy. When their children reached four years old, the researchers measured the kids’ grip strength and muscle mass. They found that higher levels of vitamin D in the mother correlated with stronger grip strength in the child. Furthermore, there was an additional, albeit weaker, relationship between the mother’s vitamin D and the child’s muscle mass.

According to researcher Nicholas Harvey, these associations between maternal vitamin D and offspring muscle strength could have significant consequences for the children’s later health. Since muscle strength peaks in young adulthood before declining as we age, low grip strength in adulthood is associated with negative health outcomes such as diabetes, falls, and fractures.

Harvey believes that the greater muscle strength observed in these four-year-olds will likely continue into adulthood, potentially helping to reduce the burden of illness linked to age-related muscle loss.

Keeping Muscles Strong Throughout Your Life

This research underscores the importance of maintaining adequate vitamin D levels, both during pregnancy and throughout our lives, in order to support strong and healthy muscles. So, how can we ensure that we’re getting enough of this vital nutrient?

1. Natural Sunlight

The most efficient way for our bodies to produce vitamin D is through exposure to sunlight. Aim for 10-30 minutes of sun exposure a few times each week, depending on your skin tone and the strength of the sun. Bear in mind, too much sun exposure can lead to skin damage and an increased risk of skin cancer, so practice sun safety.

2. Food Sources

While obtaining vitamin D through food sources can be challenging, since it is naturally present in very few foods, some vitamin D-rich options include fatty fish, such as salmon, mackerel, or tuna, and fish liver oil, as well as small amounts in beef liver, egg yolks, and cheese. Fortified foods, like some dairy products, orange juice, and cereals, also provide vitamin D.

3. Vitamin D Supplements

Many individuals don’t get sufficient vitamin D through sunlight and diet alone, making supplements a necessary addition. Consult with your healthcare provider to determine the right dosage for you, since too much vitamin D from supplements can be harmful.

4. Guidelines for Pregnant Women

For pregnant women, the American College of Obstetricians and Gynecologists advises a daily vitamin D intake of 600 to 1,000 IU. A prenatal vitamin typically contains 600 IU, which should suffice for most women. However, healthcare providers might recommend higher doses for certain patients, such as those with darker skin or living in areas with less sunlight.


Vitamin D has always been celebrated for its role in bone health, but its importance for maintaining muscle strength is arguably just as significant. Ensuring that both adults and children receive the recommended daily amount is essential for keeping muscles strong and healthy throughout our lives.