Healthy aging, what does that mean to you? To some, it might mean living to a ripe old age, to some it might mean having plump, wrinkle-free skin into their 80’s. To me, I must admit it means a more functional thing, like being able to get down to and up off the floor without creaking, still being able to get out of the house, travel, meet with friends, look after my loved ones and still remember it all at the end of the day.
There are endless supplements purported to help with healthy aging and no doubt not one supplement or intervention is going to be the magic bullet. We have talked in the past in this blog about resistance training, protein intake & creatine supplementation. However, recent attention has turned to magnesium.
What does magnesium do?
Magnesium is involved in lots of cellular processes in the body, it does not have one function. It is thought to prevent aging by having a stabilising effect on DNA, defending cells from reactive oxygen species and stimulating DNA repair. It has also been possibly connected to cardiovascular disease, type 2 diabetes, asthma, psychiatric disorders, some cancers, cognitive decline, muscle health and the list goes on.
The main attention seems to be on its potential benefits with regards to sleep and cognitive decline.
[Barbagallo M, Veronese M and Dominguez LJ. Magnesium in Ageing, Health and Diseases. Nutrients 2021;13:463]
Magnesium and sleep
This area has garnered a lot of attention. And obviously, a good night’s sleep is important to safeguard health, we all know that. We all have better cognition, make better decisions, have better hand-eye coordination, better mood, make better food choices and have better skin (!) after having one or several good nights’ sleep.
It is thought magnesium helps by blocking NMDA-gated ion channels and potentiating GABAergic neurotransmission, both of which are needed to facilitate and maintain sleep.
[He C, Wang B, Chen X et al. The Mechanisms of Magnesium in Sleep Disorders. Nature and Science of Sleep 2025;17:2639-2656]
Magnesium and cognition
There are also studies showing lower blood concentrations of magnesium in adults with reduced cognitive function.
There are now studies showing that supplementation with magnesium (possibly amongst other supplements such as Vit D3, C and B6) has shown improvements in cognitive performance and intelligence.
[Lopresti AL and Smith SJ. The effects of magnesium L-threonate (Magtein®) on cognitive performance and sleep quality in adults: a randomised, double-blind, placebo-controlled trial. Front Nutr 2026;12:1729164.]
[Kaufman MW, DeParis S, Oppezzo M et al. Nutritional Supplements for Healthy Aging: A Critical Review. Am J Lifestyle Med 2024;19:346-360]
[Chen C, Xun P, Unverzagt F et al. Serum magnesium concentration and incident cognitive impairment: the reasons for geographic and racial differences in stroke study. Eur J Nutr 2021;60:1511-1520.]
Magnesium and the skin
I did also find 2 studies that showed some beneficial activity of magnesium supplementation on the skin.
One group in Japan, funded by Shiseido, performed a study on keratinocyte cell cultures in 2022. They found that magnesium chloride supplementation was helpful in reducing UVB-induced oxidative stress in the skin.
The second study was from Italy, looking at the use of a herbal supplement containing Venerinase (an extract of rhodiola rosea, tribulus terrestris, moringa oleifera & undaria pinnatifida), folic acid, vitamins B1, B2, B12 and magnesium. 40 women aged 40-60 years with minimal/moderate actinic damage were instructed to take 9g daily for the study duration of 4 months. They found a reduction in wrinkles & facial redness caused by a reduction in vascular pattern and collagen density, possibly caused by stromal remodelling.
[Shu S, Kobayashi M, Marunaka K et al. Magnesium Supplementation Attenuates Ultraviolet-B-Induced Damage Mediated through Elevation of Polyamine Production in Human HaCaT Keratinocytes. Cells 2022;11:2268.]
[Michelini S, Greco ME, Vespasiani G et al. Non-invasive Imaging for the Evaluation of a New Oral Supplement in Skin Ageing: A Case-Controlled Study. Skin Res & Technol 2025;31: e70171]
Where do we get magnesium?
We get the majority of our magnesium from our diet; think of a plant-based diet, bananas, leafy greens, beans, seeds and nuts. However, there are claims that the Western diet that is rich in processed foods is deficient in magnesium and that the levels of magnesium reduce with age due to continued insufficient intake and age-related diseases or medications. So not surprisingly, sales of magnesium supplements are surging.
[Will magnesium supplements help you relax? Science & technology section, The Economist Feb 27th 2026. ]
Should we trust the studies?
I think the trouble, as always, is that the studies looking at magnesium supplements were of low to very low quality. The types of magnesium salts (and there are many, -oxide, -citrate, – L-aspartate, -glycinate and – threonate for example) vary, the species studied vary, and all sorts of variables can affect magnesium levels such as intake, intestinal absorption, kidney excretion, storage in bones and use by different tissues. Also only <1% of total magnesium is extracellular so it would be possible to have low intracellular levels of magnesium with a normal total magnesium level.
Is magnesium supplementation safe?
Well that depends on how much you ingest per day. The studies do say that intestinal absorption of magnesium falls with age, together with increased loss of magnesium via the kidneys, and increased polypharmacy in the elderly which also causes increased loss of magnesium.
Reported side effects were mild, the main one being increased bowel movements (as high dose magnesium is used as a laxative).
So should I take magnesium supplements?
The studies report that a healthy person needs to consume between 5-7mg/kg/day of magnesium. Most of this should be through your diet and what you drink but knowing how much magnesium you’re eating and drinking and then absorbing is difficult. If you eat a heavily processed diet with little in the way of plant-based foods, then supplementation may be required but clearly, further, larger studies are required to standardise the doses and forms for clinical practice.
Kind regards,
Sandy
Dr Sandy Flann, Consultant Dermatologist
