Medical disclaimer: SnoozeVerdict summarizes what people say about sleep supplements on Reddit. It is not medical advice, and nothing here is meant to diagnose, treat, cure, or prevent any disease. These statements have not been evaluated by the Food and Drug Administration. Talk to your doctor or pharmacist before starting a supplement, especially if you are pregnant, take medicines (including sleep or mood medicines), or have a medical condition. Poor sleep that lasts for months, loud snoring or gasping at night, or falling asleep during the day while driving or working needs a doctor, not a supplement. Full disclaimer.

Magnesium · dosage and timing

Magnesium Dosage and Timing: What Owners Report

About this entry (Magnesium (form not stated)): Comments that name magnesium without a form (or a multi-form blend). Counted separately from glycinate/threonate/taurate.

In 68 Reddit owner comments that give an amount, the typical Magnesium dose was 210 mg (middle half: 146 to 400 mg). The timing people mention most is at night or before bed (269 comments). These numbers describe what people with sleep problems say they take on Reddit (May 2026 to October 2026); they are not dosing advice. Follow the label and ask a doctor or pharmacist, especially if you take medicines.

Amounts owners mention

Unit	Comments	Typical (median)	Middle half	Most-mentioned amounts
mg	68	210	146 to 400	200 (16), 300 (11), 400 (9)
capsules or tablets	4	1.5	1 to 2	2 (2), 1 (2)

Counted from amounts written next to the name Magnesium in 75 owner comments (a comment can give more than one amount). Products differ in strength, so a number of capsules or scoops is not comparable between brands. Most-mentioned: 200 mg (16), 300 mg (11), 400 mg (9).

What studies and NIH sources say

A small 2012 double-blind trial in older adults with insomnia compared 500 mg of magnesium a day with placebo for 8 weeks.^[PubMed]
The NIH upper limit for magnesium from supplements is 350 mg a day for adults unless a doctor advises more; higher doses commonly cause diarrhea, and people with kidney disease are at higher risk of magnesium build-up.^{[NIH Office of Dietary Supplements]}
Magnesium can reduce absorption of some antibiotics and osteoporosis drugs, so doses are usually spaced apart.^{[NIH Office of Dietary Supplements]}

When people take it

Timing mentioned	Owner comments
At night or before bed	269
In the morning	49
With or after food	11
Split into two doses	4
On an empty stomach	4

Phrases such as "before bed", "in the morning" or "with food" near the name Magnesium.

How long it takes, according to owners

Timeframe mentioned	Comments	Positive	Negative
Minutes to hours	6	2	1
Within the first week	8	4	0
1 to 4 weeks	8	4	0
More than a month	7	6	1

28 owner comments mention a timeframe such as "after 2 weeks", "within an hour" or "it took a month". A timeframe can describe when someone noticed a change or how long they tried it before giving up, so read it as a rough signal.

4/5 Fast-actingDeeper sleep
“In terms of supplements, I have found magnesium to be the most helpful for me.”

owner comment via r/sleep · 2026-09-08 · 8 upvotes

1/5 Side effectsTaste & form
“I'm here 9 years later because I watched a video on tt where a guy was saying that if you take 2 pills of magnesium before sleep, you'll thank him all your life.”

owner comment via r/Supplements · 2026-06-14 · 1 upvotes

4/5 Deeper sleep
“But the additional of the grey scale and magnesium have helped with that next level.”

owner comment via r/sleep · 2026-05-22 · 1 upvotes

In their words

4/5 Deeper sleep
“and i started taking magnesium before bed, the glycinate kind, it helped with the body aches and sleep quality”

owner comment via r/Supplements · 2026-08-14 · 20 upvotes

5/5
“I use it at night with triple magnesium amazing sleep”

owner comment via r/Supplements · 2026-06-09 · 14 upvotes

4/5
“magnesium before bed helps me sleep better”

owner comment via r/Supplements · 2026-07-05 · 14 upvotes

4/5
“Recently I've seen improvement by taking magnesium and taurine before bed.”

owner comment via r/sleep · 2026-07-30 · 13 upvotes

3/5 Side effects
“Not commenting on your sheets but if you use magnesium before bed it will help regulate your body temperature as it supports the function of over 300 biochemical processes in your body.”

owner comment via r/sleep · 2026-07-11 · 3 upvotes

4/5 Deeper sleepFalling asleep faster
“I had similar experience with magnesium helping me get sleepy but not staying asleep part.”

owner comment via r/sleep · 2026-06-03 · 11 upvotes

Magnesium (form not stated) overall: 4.2 from 938 owner comments.

Frequently asked

How much Magnesium do people take?

In 68 Reddit owner comments that give an amount, the typical Magnesium dose was 210 mg (middle half: 146 to 400 mg). That is what people report, not a recommended dose; follow the product label and your doctor's advice.

When do people take Magnesium?

The timing people mention most is at night or before bed (269 comments). In the morning: 49; With or after food: 11.

How long does Magnesium take to work?

28 owner comments mention a timeframe near Magnesium (for example "after two weeks" or "within an hour"). Minutes to hours: 6; Within the first week: 8; 1 to 4 weeks: 8; More than a month: 7. Individual experiences vary widely.