Magnesium – Is It All It’s Cracked Up to Be?

If you’re a parent, you’ve likely encountered discussions about magnesium – whether in parenting forums, supplement shelves, or targeted social media ads. It appears to be the latest supplement trend, promising that your child will sleep better or enjoy a calmer mood – both of which are, of course, hugely appealing. However, with all the hype, it’s easy to wonder if this supplement truly lives up to expectations and whether it’s even necessary.  

In this blog, you’ll find out:

• What is magnesium, and why is it needed in the body
• What foods contain magnesium, and how much magnesium do children need?
• Considerations for magnesium supplementation, and whether you should save your money!

What is magnesium, and why do children need magnesium?

Magnesium is a nutrient we all need to stay healthy, and it can be found abundantly in a wide range of foods!  Magnesium is needed in the body for lots of reasons, in fact over 300 body processes, which include;

• Helping nerves and muscles work properly (and together)
• Supporting blood sugar levels and regulation
• Making bone (alongside calcium and vitamin D, it’s great for bone health)
• Supporting blood pressure
• Supporting brain health and mood
• Helps release energy from the food we eat

How much magnesium do children need?

The amount of magnesium children need depends on their age.   Here’s a table to check your child’s magnesium requirements compared to their age.  Remember, whilst this is a daily recommendation, what is important is intake over time.  It’s likely your child will consume more magnesium some days, and less on others.

*For babies under 12 months of age, breast milk and/or formula milk will provide magnesium to support their nutritional requirements.

What foods contain magnesium?

A wide variety of foods contain magnesium, many of which your child is likely to be already eating, these include;

• Nuts and seeds, especially pumpkin seeds, cashew nuts, almonds and peanuts (offer milled or as a butter for young children)
• Cereals, e.g. shredded wheat, Weetabix
• Yoghurt and Soy yoghurt
• Potato
• Green vegetables e.g. spinach
• Wholegrains e.g. brown rice, oats
• Wholemeal bread
• Beans, e.g. black beans, kidney beans, edamame beans
• Banana
• Avocado

Easy ways to boost the magnesium content of your child’s diet, with food include;

• Adding whole (or crushed/milled) pumpkin seeds and/or chia seeds to porridge, cereal, flapjacks, pancake mix, muffins, on top of yoghurt or even savoury dishes like pasta bake
• Add frozen spinach cubes to sauces, stews, pancake mix and smoothies 
• Regularly including fortified cereals containing magnesium in your child’s diet
• Adding a tin of beans or pulses to curries, stews, bolognese or fajita mix

As an example, a toddler could meet their magnesium requirement for the day by consuming this across one meal and snack;

• Breakfast: One Weetabix with 150mls milk, a small banana and 1 tsp peanut butter
• Snack: 150ml of yoghurt

Does your child need a magnesium supplement?

In the UK, there is currently insufficient robust evidence to suggest that children are consistently falling short of their recommended magnesium intake, warranting regular supplementation. That said, with changing dietary patterns in the UK and increased intake of certain food types, alongside increasing food poverty rates, it’s a nutrient worth keeping an eye on.    There may be groups, of course, at higher risk of low magnesium intake, such as: 

• Children with one or more food allergies (especially if avoiding dairy, peanuts, wheat, and tree nuts)
• Children who are highly selective or ‘fussy’ eaters.

Ideally, a paediatric dietitian would complete an individualised dietary assessment to determine if magnesium supplementation is needed and in what doses. It is essential to be aware that prolonged low magnesium levels can lead to a magnesium deficiency, but this is very rare.

If you are using magnesium supplementation with your child, please be aware that it may cause common side effects, such as diarrhoea or loose stools.  There are different types of magnesium; for example, magnesium glycinate is kinder to the digestive system than other types.

Will magnesium supplementation help your child sleep better?

Whilst some adult studies have shown an association between magnesium status and sleep quality, little scientific evidence is available in children that suggests magnesium supplementation improves sleep quality or duration.  If you are experiencing sleep challenges, consider reviewing various factors influencing your child’s sleep routine, hygiene, and environment before resorting to expensive supplementation that may not be necessary.

Be aware that other nutrients can impact sleep, such as iron, and a deficiency of this mineral is much more common in children than a magnesium deficiency.