Check a pair

Calcium and Iron together

Checked on Calcium and Iron Bisglycinate — the best-absorbed forms people actually buy. Other forms of the same two behave the same way here: the interaction belongs to the mineral, not to the carrier.

Separate by 2-4 hours to avoid the interaction below.

40 compatibility
0 synergies
1 conflict

Verdict

Major clinical significance
Compatibility score 40 out of 100
40 out of 100
Needs attention Separate by 2-4 hours to avoid the interaction below.

Timing plan

Separate them
Calcium Divided doses with meals 1,000-1,200 mg
wait 2–4 hours
Iron Bisglycinate With vitamin c between meals 18-65 mg elemental

These two compete on absorption. Splitting the day keeps both effective.

What clashes

1 documented
!
Inhibits iron absorption

Iron Bisglycinate → Calcium

Competition for intestinal transporters · major

What each one is for

Two different jobs — that is why the pairing question comes up at all

Calcium — bone health & muscle function.

Usual daily dose 1,000-1,200 mg, taken divided doses with meals. The ceiling is 2500 mg a day (NIH ODS). It is named as the suspect product in 569 FDA reports. Evidence grade A.

Iron Bisglycinate — gentle high-absorption iron.

Usual daily dose 18-65 mg elemental, taken with vitamin c between meals. The ceiling is 45 mg a day (NIH ODS). It is named as the suspect product in 340 FDA reports. Evidence grade A.

Side by side

CalciumIron Bisglycinate
Absorption score 30/100 90/100
Elemental mineral 100% 27.4%
Cost per 100 mg delivered $0.2 $9.77
Safety rating 8/10 7/10
Cost per month $20 $30
Daily dose 1,000-1,200 mg 18-65 mg elemental
Best timing Divided doses with meals With vitamin c between meals
Evidence level A A

How this score was built

  • Baseline for any untested pair: 70
  • −30 — major clinical conflict
  • = 40 out of 100

Where to buy

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Buying both? Check the timing plan above so they do not cancel each other out.

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Common questions

Can you take Calcium and Iron Bisglycinate together?

Separate by 2-4 hours to avoid the interaction below. The pair scores 40 out of 100, based on 1 documented interaction records.

What should you not take with Calcium?

In this pairing the issue is: Inhibits iron absorption Separate them by two to four hours.

When should you take Calcium and Iron Bisglycinate?

Calcium: Divided doses with meals. Iron Bisglycinate: With vitamin c between meals. Keep at least a two-hour gap between them.

Where to go next