Expert Answer
What is the best time of day to take supplements?
Quick Answer
Two rules cover most of it. Take fat-soluble vitamins with a meal that has fat in it, and put anything sedating at night. Huberman takes magnesium 30 to 60 minutes before sleep, Attia takes 600 mg of ashwagandha at night, and Patrick times melatonin to the 2 to 3 hours before bed when the body makes its own.
What Researchers Say
Splits the day in two. Vitamin-mineral supplements go with food early, because B vitamins and zinc upset some people on an empty stomach. Anything designed to make you sleepy goes in the last hour.
“I was asked, do magnesium need to be taken with or without food or before sleep? If you're going to go that route it should be taken 30 to 60 minutes before sleep, 'cause it's designed to make you sleepy.”
Andrew Huberman, on the record @ 01:01:22
Puts his own sedating supplement at night rather than splitting it across the day, and names the dose he takes.
“in the night I take, um, ashwagandha. I take 600, uh, milligrams of ashwagandha. I recently switched to the Solgar brand.”
Peter Attia, on the record @ 06:08
Times melatonin to the body's own rise rather than to bedtime itself, which is the clearest example of matching a supplement to a physiological window instead of a habit.
“before bed our bodies naturally start to produce melatonin around 2 to 3 hours before we go to sleep melatonin has been shown to bind to receptors on the pancreas and this signals to the pancreas to stop producing insulin”
Rhonda Patrick, on the record @ 01:23
Runs the most rigidly timed protocol of the five. Supplements land in fixed slots around the morning meal and the workout rather than whenever he remembers them.
“Prior to working out I'm going to make a little concoction. First, a little bit of water. I'll drink a total of about 48 ounces today. This is two and a half grams of creatine.”
Bryan Johnson, on the record @ 03:05
Makes the absorption case for taking fat-soluble vitamins A, D, E and K with a meal that contains fat. The number-bearing line in that exchange is his guest's, not his, so no receipt is shown.
Detailed Answer
The short version
Timing changes the outcome for a small number of supplements and almost nothing for the rest. Get the two rules right and stop optimizing.
Rule one: fat-soluble vitamins go with a meal
Vitamins A, D, E and K need dietary fat to cross the gut wall. Taken on an empty stomach with water, less of them gets in. Mark Hyman makes this point directly about vitamin D, and it applies to the whole fat-soluble group.
Andrew Huberman extends the same logic to B vitamins, zinc and CoQ10, though for a different reason. Those tend to cause stomach upset without food rather than absorbing poorly.
Rule two: sedating things go at night
Magnesium is the clearest case. Huberman's line is that if you are taking it for sleep, it belongs 30 to 60 minutes before bed, because that is what it is for. Peter Attia does the same with ashwagandha, taking his 600 mg at night.
Rhonda Patrick applies the sharpest version of this to melatonin. Your own melatonin starts rising 2 to 3 hours before sleep, so that is the window a supplement should match.
Where timing does not matter much
Creatine is the standard example. Total daily intake is what fills the muscle and brain stores, so taking it before or after training changes very little. Bryan Johnson takes his 2.5 g before the workout, but the reason is routine, not absorption.
Omega-3 and vitamin D behave the same way. Take them with a meal, take them daily, and stop tuning the clock.
The rule that beats all the others
Whatever schedule you pick has to be one you actually keep. A supplement taken at the theoretically ideal moment four days a week loses to the same supplement taken with breakfast every day.
Related Questions
Should you take supplements in the morning or at night?
Split them. Vitamin-mineral supplements, vitamin D and omega-3 go with a morning meal. Magnesium, ashwagandha and melatonin go at night, because all three are meant to make you sleepy.
Do supplements need to be taken with food?
Fat-soluble vitamins do, because they need dietary fat to absorb. Zinc, CoQ10 and B vitamins are better with food mainly to avoid stomach upset. Creatine does not care.
How long before bed should you take magnesium?
Huberman puts it at 30 to 60 minutes before sleep when the goal is sleep. Patrick times melatonin further out, to the 2 to 3 hours before bed when the body's own production rises.
Does it matter what time you take creatine?
Not much. Daily total is what fills the stores. Johnson takes his before training out of routine rather than for absorption.
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