Should you take magnesium for sleep?

We get asked about magnesium for sleep quite a lot. It’s one of the more common supplements out there, but what exactly is this mineral? And why does magnesium make you sleepy?

Magnesium is essential to the functioning of your body and brain. It’s a vital catalyst for many enzymes, enabling over 300 regular reactions. At any one time, you’d expect there to be about 25g of magnesium in your body, but most of that is tied up in your bones. It also always comes from external sources—much like iron and calcium. As a metal, your body can’t produce it.

Does magnesium help you sleep?

Studies have shown magnesium to be beneficial when it comes to sleep. It plays a role in the process, activating the parasympathetic nervous system and helping regulate the production and release of melatonin—the hormone that guides sleep-wake cycles. 

However, supplemental magnesium’s effect on sleep has also not been tested extensively. Magnesium in the diet has been shown to aid sleep, and supplements have been shown to help older individuals in this regard, but there’s not enough data when it comes to the rest of the population.

Is melatonin or magnesium better for sleep?

Both magnesium and melatonin are famed for helping you drift off to dreamland, but which one works better? The answer to this isn't straight forwarded, as they address different sleep goals.

According to the Sleep Foundation, magnesium helps the body relax and reduces stress to help you sleep longer. In contrast, melatonin helps you get to sleep faster.

Magnesium for sleep (and more!)

There are other benefits of magnesium beyond better sleep. It helps maintain a healthy amount of GABA—a neurotransmitter that calms excitement in the central nervous system and aids relaxation.

It’s also essential for normal muscle and heart function, and is excellent for the health and structure of your bones. All in all, a good one to have around.

Magnesium in food

For magnesium, your first stop should always be your diet. Regular foods that have a lot of magnesium include:

• Spinach

• Wholemeal bread

• Nuts

• Pulses

But if you want a more comprehensive list, take a look here.

It’s more than possible to get enough magnesium from your diet. However, you can also take a magnesium supplement for sleep, either as a spray, gel, or a pill.

How much magnesium should I take at night for sleep?

There are no clear recommendations on how much for magnesium for sleep specifically, however, the NHS recommends getting between 270mg and 300mg of magnesium a day. Given the safe upper limit is around 400mg, make sure that any supplements keep you below that level.

Side effects of taking too much include nausea, abdominal cramps and diarrhoea (it’s a common ingredient in over-the-counter laxatives), and taking supplemental magnesium can also interfere with certain medications, like osteoporosis medicine, and some antibiotics.

When should you take magnesium for sleep?

When to take magnesium for sleep depends on your bedtime and evening routine. If you're taking a supplement, it's recommended to do so 30 minutes before you go to bed.

Which form of magnesium is best for sleep?

The most important thing when you're taking magnesium for sleep is to make sure what you're taking is actually effective. Magnesium comes in countless compounds, and you’ll absorb each at a different rate. For example, you’ll need to take significantly more magnesium oxide than magnesium sulphate. 

It can also affect the uptake of certain other nutrients, such as zinc, so it’s always important to check before taking magnesium with anything else.

What else will help me sleep?

While magnesium in your diet is great for sleep, it’s only one part of the puzzle. Other nutrients can also affect melatonin production and regulation, as well as other factors in a deep sleep. These include various B vitamins (B1, B2, B6 and B12 in particular), as well as vitamins D and E.

There are also certain habits and behaviours you can implement to help yourself sleep better. Small things like reducing screen time before bed, maintaining a steady routine, and leaving a gap before eating and going to bed can all make a huge difference.

Want to learn to sleep better?

• Find out more about the nutrients that make the most difference

• See how you can change your routine to effect the best sleep possible

• Listen to our conversation with Dr Sophie Bostock—the Sleep Scientist