A complete safety, timing, and dosage guide for combining Magnesium (Citrate, Glycinate, Oxide, Threonate) with Krill Oil — including how the two supplements interact, the best time of day to take each, and which populations should be careful.
Yes, you can take magnesium and krill oil together — they are safe to combine and don't interfere with each other's absorption or activity in the body.
Magnesium and krill oil together are safe for most adults. There is no meaningful interaction between the mineral and the marine oil, and combining them does not require special timing or dosing adjustments.
Magnesium is absorbed mainly in the small intestine via TRPM6/TRPM7 ion channels and paracellular transport. Krill oil is a fat-soluble mixture of phospholipid-bound EPA and DHA, plus astaxanthin, which is emulsified by bile salts and absorbed into lymphatic vessels. These two pathways are entirely separate, so neither supplement competes with the other for a transporter or receptor. The only theoretical overlap is that very large doses of magnesium (especially as oxide) can cause loose stools, and if that happens at the exact same time as krill oil, the faster transit could reduce how much oil is digested. In practice, with typical doses, this is not a concern.
If you take both, the simplest strategy is to take them together with breakfast or dinner. Because krill oil needs dietary fat to be absorbed, pair it with a meal that includes some fat, and take magnesium at the same time or right after that meal. If you use magnesium oxide and notice diarrhea, you can switch to magnesium glycinate or citrate, or split the dose and take half in the morning and half in the evening. If you miss a dose, just continue with your regular schedule the next day; there is no need to double up. You can take them in the same mouthful, but if you prefer, separating them by 30–60 minutes is also fine.
Magnesium oxide has the lowest absorption and often acts as a laxative; if you take that form, eating it with krill oil and a meal may reduce the laxative effect but doesn't change the safety of the pair. Magnesium citrate is better absorbed and generally well tolerated, while glycinate and threonate are also highly bioavailable and gentle on the stomach. No form of magnesium has a known interaction with krill oil, so choose the form that your digestive system handles best.
This pairing is not a classic 'stack', but both appear in basic cardiovascular and wellness support routines alongside CoQ10, vitamin D, and fish oil or krill oil. Some all-in-one heart-health supplements combine krill oil, magnesium, CoQ10, and vitamin D, though the combination is more about covering multiple bases than a documented synergy.
Yes, I routinely tell my clients it is safe to take them at the same time. There is no competition between the mineral and the oil, and taking them with food can help your body absorb both comfortably.
Yes, taking both daily is safe for healthy adults. I recommend staying within the daily magnesium supplement dose of no more than 350 mg, and following the krill oil label instructions for a normal serving.
You do not need to wait. You can take them together, or separate them by a few minutes if you prefer.
No, they do not compete. Magnesium is absorbed through mineral channels in the small intestine, while krill oil is absorbed along with dietary fat through the lymphatic system. Their pathways are separate, so taking them together won't reduce the effectiveness of either.
Most adults can take them together, but I advise caution for people on blood thinners and those with kidney or parathyroid conditions. If you are about to have surgery, you may want to stop krill oil a week or two beforehand and ask your surgeon.
I recommend taking both with food, specifically a meal that has some fat, because krill oil needs dietary fat for absorption. Magnesium is well tolerated with food, and this also reduces any chance of stomach upset.
Reviewed by Caroline M. on April 10, 2026 for accuracy against the sources listed above. This page is educational and is not a substitute for professional medical advice.
The matrix has 86 supplements and 7310 pairwise interactions. Click any cell to see the full breakdown.