How Much Magnesium Do Kids Need? UK Reference Intakes by Age
Short post, useful numbers. How much magnesium kids need changes a lot as they grow, and the UK reference intakes are the sensible place to anchor every decision, from what's on the plate to whether a supplement dose is appropriate.
The UK numbers, age by age
| Age | Daily reference intake |
|---|---|
| 1 to 3 years | 85mg |
| 4 to 6 years | 120mg |
| 7 to 10 years | 200mg |
| 11 years and up | 300mg |
Two things stand out. First, the jump between age bands is steep: a seven-year-old needs well over double what a toddler does. Second, these are food-first targets. The reference intake describes what should come from the whole diet, not from a bottle.
What those numbers look like on a plate
Magnesium adds up in ordinary food faster than parents expect. A rough feel for it:
- A bowl of porridge oats gets a decent way toward a toddler's day (more in magnesium for toddlers)
- Half a tin of baked beans makes a solid contribution
- A banana, a pot of yoghurt, a slice of wholemeal toast all chip in usefully
- A tablespoon of smooth peanut butter or a sprinkle of ground pumpkin seeds punches above its weight
- A couple of squares of dark chocolate: the negotiation nobody loses
A child who eats a genuinely varied week can meet their number from food alone, and that's the goal. The complications arrive with fussy phases, when whole food groups go on strike; our fussy eaters guide deals with that reality.
Where supplement doses fit
A well-designed children's supplement doesn't try to supply the whole reference intake, because food is already providing some. It tops up. For context, here's how our own dosing sits against the UK numbers:
| Serving | Magnesium | Share of daily RI |
|---|---|---|
| 2.5ml (ages 1 to 5) | 35mg | 41% at ages 1-3, 29% at ages 4-5 |
| 5ml (ages 5 to 14) | 70mg | 58% at 5-6, 36% at 7-10, 24% at 11+ |
That's deliberate headroom: a meaningful top-up on a patchy eating day, comfortably inside the reference intake even on a good one. It's also why "more is better" is the wrong instinct with minerals. Stick to the dose for your child's age, don't exceed it, and if your child has a medical condition or takes medication, talk to your GP first.
The right dose isn't the biggest one. It's the one that fits alongside food.
For the bigger picture, from what magnesium does to how to choose a form, start at the parent's guide to magnesium for kids.
Our magnesium
Liposomal Magnesium for Kids (Age 1+) is truly unflavoured, gentle on little tummies, and built for absorption. Magnesium contributes to the normal functioning of the nervous system.*
*Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Consult your healthcare provider before use if your child has a medical condition or takes medication.