Why 450mg Keeps Coming Up
People walk in asking for magnesium and most of them already know they want citrate. What they do not know is whether 450mg is right for them, whether to take it in the morning or at night, and whether it matters if they have eaten first. Those three questions come up at the till more often than almost anything else in the shop.
- People walk in asking for magnesium and most of them already know they want citrate.
- Magnesium comes in a long list of compounds and the form determines how well your body can actually use it.
I have been selling supplements for thirty years. Magnesium citrate is one of the few forms I genuinely like. It absorbs well, it is gentle on most stomachs, and the 450mg dose sits in a useful range for the majority of adults. But the number on the label is only part of the story. What you do with the capsule matters just as much.
What Makes Citrate Different From Other Forms
Magnesium comes in a long list of compounds and the form determines how well your body can actually use it. Citrate is bound to citric acid. That bond makes it water soluble and reasonably easy to absorb compared to older forms like oxide, which is cheap to manufacture but passes through a lot of people without doing much at all.
Here is a quick comparison of the forms I stock and what separates them:
| Form | Absorption | Best suited for | Notes |
|---|---|---|---|
| Magnesium Oxide | Low | Occasional use only | Very common on supermarket shelves |
| Magnesium Citrate | Good | General daily use | Gentle, well tolerated, my most-sold form |
| Magnesium Glycinate / Bisglycinate | High | Sensitive stomachs, sleep support | Slower-acting, calmer on digestion |
| Magnesium Malate | Good | Daytime use, muscle function | Less widely available |
| Magnesium Threonate | Specialist | Cognitive function focus | Higher cost, niche use |
If you want more detail on how citrate and glycinate compare head to head, I wrote a full post on Magnesium Glycinate vs Citrate: Which One Should You Take? which covers that properly.
Is 450mg the Right Amount for You
The 450mg figure is not random. It sits close to the reference nutrient intake for most adults and it is a dose that tends to be effective without causing the loose stool effect that higher amounts can produce. Magnesium citrate at very high doses has a laxative action. That is not a rumour, it is actually used clinically for that purpose. At 450mg most people are nowhere near that territory, but it is worth knowing.
Where 450mg tends to work well:
- Adults eating a varied diet - Tops up what food provides without going over the top
- People under regular physical or mental stress - Magnesium contributes to normal psychological function and to the reduction of tiredness and fatigue, both EFSA-authorised claims
- Those with muscle function as the main priority - Magnesium contributes to normal muscle function, which is why athletes reach for it
- Anyone who tried a lower dose and felt nothing - 150mg or 200mg products exist but for many people 450mg is where results actually show up
If you are on medication for any heart, kidney or bowel condition, talk to your GP before adding magnesium. That is not me being overly cautious. It is genuinely relevant for some drugs, including certain diuretics and antibiotics.
Timing: Morning, Evening or Split Dose
This is where I spend most of the conversation at the counter. The capsule works the same biochemically at any hour. What changes is how it fits your routine and what you are hoping to notice.
- Evening - The most common choice. Magnesium contributes to normal nervous system function and many people find taking it an hour or so before bed fits naturally into a wind-down routine. If you associate magnesium with sleep, this is when most of my customers take it.
- Morning - Works well if your priority is energy, concentration or muscle function through the day. Magnesium contributes to normal energy-yielding metabolism, so there is a reasonable logic to morning dosing if that is your focus.
- Split dose - Some people take 225mg twice a day. This can reduce any mild digestive sensitivity and keeps levels steadier. Not always practical but worth knowing as an option.
There is no universally correct answer here. My honest advice is to pick the time you will actually remember, because consistency matters far more than the precise hour on the clock.
Food or No Food: What Actually Changes
This is the question that surprises people most. Magnesium citrate is one of the better-absorbed forms partly because the citric acid component means it does not rely heavily on stomach acid to dissolve. That gives it an advantage over oxide and carbonate forms, which need an acidic environment to break down properly.
That said, taking it with or after food is still the approach I recommend to most people, for two reasons. First, food stimulates stomach acid production anyway, which does no harm to absorption. Second, and more practically, some people find magnesium on an empty stomach slightly unsettling. Not everyone. But enough that I mention it. If you have a cast iron stomach you can take it whenever. If you are a bit sensitive, take it with your evening meal or just after.
What you eat alongside it can matter too. Calcium-rich foods taken at the same time compete slightly for absorption pathways, so pairing magnesium with a glass of milk is not ideal. Phytic acid in very high-fibre foods can bind to minerals. In practice, for a normal mixed meal this is not something worth losing sleep over. It becomes relevant if you are taking multiple mineral supplements at once, in which case spacing them out across the day is sensible.
The Products I Actually Recommend at 450mg
I stock a few options and the right one depends on whether you want a no-frills capsule, a combined formula, or a premium brand with full ingredient transparency.
For straightforward daily use, the Magnesium Citrate 450mg Capsules by LSC Supplements is what I reach for first. It is our own label, the dose is exactly what it says, and the price is honest. Nothing unnecessary in the capsule.
View in the shop
If you want the same form from a brand with a longer track record and full supply chain transparency, Viridian Magnesium Citrate is excellent. Viridian publish their ingredient sourcing, they do not use artificial additives, and the quality is consistent. I have stocked them for years without a single complaint about the product.
For anyone who wants B6 alongside their magnesium, which makes sense because B6 contributes to normal energy metabolism and psychological function just as magnesium does, Viridian Magnesium and B6 (100mg Magnesium Citrate, 90 Capsules) is a practical combined option. The magnesium dose per capsule is lower so you would take more capsules to reach 450mg, but the combination works well for people who want both nutrients in one.
FAQ
Can I take magnesium citrate 450mg every day?
Yes, daily use is the norm. Magnesium is not something you load and stop. It works best taken consistently over weeks, which is why most products come in a 60-capsule bottle. If you experience loose stools, try taking it with food or consider splitting the dose.
Will 450mg make me tired during the day?
Magnesium is not a sedative. It contributes to normal nervous system function, which some people interpret as a calming effect, but it does not cause drowsiness in the way that an antihistamine would. Most people taking it in the morning notice no effect on alertness at all.
Should I take magnesium with vitamin D?
Magnesium plays a role in how the body uses vitamin D, so combining them is not unusual. I often suggest people look at both if they are taking vitamin D through the winter. Neither replaces the other. They support different things and happen to work alongside each other reasonably well.
Is 450mg safe if I am on prescription medication?
This is a question for your GP, not me. Magnesium interacts with certain antibiotics, bisphosphonates and medications used for heart conditions. I am not in a position to advise on that at the till and your GP is the right person to ask before you start.
What is the difference between 450mg of magnesium citrate and 450mg of elemental magnesium?
Good question and one that trips a lot of people up. Magnesium citrate is the compound, meaning it includes the citric acid part. The actual magnesium content, called elemental magnesium, is a fraction of the total weight. Always check the label for elemental magnesium per serving, not just the compound weight. Our LSC capsule lists both clearly.