Health Reference LibraryWhen is the best time to take iron, and should you take it with food?
This entry is part of the Nutri Tailor Health Reference Library — cited research on supplements, nutrients and adjacent areas of health.
Summary
Morning, on an empty stomach or with a small vitamin C rich snack, and every other day if you can manage it. Alternate days work because each dose raises hepcidin, the hormone that shuts the gut to iron for the rest of the day, and a 48 hour gap lets it fall again. Keep tea and coffee an hour away on the far side, calcium supplements two hours away, and milk, cheese and yoghurt out of the same meal. If a ferrous salt makes you feel sick, a light low calcium meal or a switch to bisglycinate beats stopping.
Effective dose
Daily or alternate days for eight to twelve weeks, then a ferritin retest; a diagnosed deficiency continues three months after the blood count recovers, on the GP’s dose.
Timing
Morning, on an empty stomach or with a small vitamin C rich snack, and every other day rather than every day if you can. The absorption studies found more iron taken up per tablet when doses were 48 hours apart, because the hormone hepcidin rises after each dose and closes the gut for the rest of the day. Keep tea and coffee an hour away on the far side, calcium supplements two hours away, and zinc at a different meal if you take a high dose of it.
Interactions
An empty stomach absorbs more but upsets more. If a ferrous salt makes you feel sick, taking it with a light low calcium meal is better than stopping, and switching to a gentle form such as bisglycinate lets you take it with breakfast without losing much. Not with milk, cheese, yoghurt, tea or coffee.
Practical framework
From the Nutri Tailor range: [iron bisglycinate with vitamin C](/products/iron-vitamin-c), 15 mg of iron with 400 mg of vitamin C, all made in the UK. This is a summary of published research, not personal health advice. Talk to your GP or a registered nutritional therapist before changing what you take, especially if you are pregnant, have a diagnosed condition or are under ongoing care.
Common misconceptions
That the hour matters more than the habit: for iron the daily total and the weeks of use decide the result. That an empty stomach is always better: for iron the answer is above, and comfort keeps people taking it.
Sources
- NIH Office of Dietary Supplements 2025. Iron: Fact Sheet for Health Professionals. National Institutes of Health, Office of Dietary Supplements.
- National Institute for Health and Care Excellence (NICE, UK government) 2024. Anaemia - iron deficiency: Clinical Knowledge Summary. NICE Clinical Knowledge Summaries.