Magnesium
Last updated: August 9, 2026
Benefits
Involved in hundreds of reactions including energy production, muscle and nerve function, blood sugar control, and bone structure.
How much you need
Recommended daily amounts by life stage, per NIH and NASEM Dietary Reference Intakes. Where the evidence hasn't been enough to set a full RDA (Recommended Dietary Allowance), NASEM sets an AI (Adequate Intake) instead — both are shown together below.
| Life stage | RDA / AI |
|---|---|
| Children 1–3 | 80 mg |
| Children 4–8 | 130 mg |
| Boys 9–13 | 240 mg |
| Girls 9–13 | 240 mg |
| Males 14–18 | 410 mg |
| Females 14–18 | 360 mg |
| Men 19–50 | 400 mg |
| Women 19–50 | 310 mg |
| Men 51–70 | 420 mg |
| Women 51–70 | 320 mg |
| Men 71+ | 420 mg |
| Women 71+ | 320 mg |
| Pregnancy 14–18 | 400 mg |
| Pregnancy 19–50 | 350 mg |
| Lactation 14–18 | 360 mg |
| Lactation 19–50 | 310 mg |
Upper limit
This limit counts Magnesium from supplements only — the amount you get from food does not count toward it.
| Life stage | Tolerable upper limit |
|---|---|
| Children 1–3 | 65 mg |
| Children 4–8 | 110 mg |
| Boys 9–13 | 350 mg |
| Girls 9–13 | 350 mg |
| Males 14–18 | 350 mg |
| Females 14–18 | 350 mg |
| Men 19–50 | 350 mg |
| Women 19–50 | 350 mg |
| Men 51–70 | 350 mg |
| Women 51–70 | 350 mg |
| Men 71+ | 350 mg |
| Women 71+ | 350 mg |
| Pregnancy 14–18 | 350 mg |
| Pregnancy 19–50 | 350 mg |
| Lactation 14–18 | 350 mg |
| Lactation 19–50 | 350 mg |
High supplemental magnesium can cause diarrhea, nausea, and abdominal cramping. Magnesium from food doesn't count toward this limit.
Best food sources
| Serving | ||
|---|---|---|
| Pumpkin and chia seeds | — | — |
| Almonds and cashews | — | — |
| Spinach | — | — |
| Black beans | — | — |
| Dark chocolate | — | — |
Absorption & caution
Absorption: Absorbed well with or without food; taking magnesium alongside a meal tends to be gentler on digestion. Absorption also varies by form — citrate and glycinate absorb more readily than oxide.
Pairings
Works well with
- Vitamin D — Magnesium helps activate vitamin D so the body can use it.
Competes with
- Calcium — Magnesium and calcium can work against each other at very high daily intakes. It's the ongoing daily amount that matters here, not the gap between them.
Body systems & goals
Body systems it supports
- Blood Sugar — Even, well-fueled energy depends on how your body handles the sugar in your food. These nutrients support the steady blood-sugar balance that keeps energy from spiking and crashing. (established evidence)
- Kidneys — Your kidneys quietly filter your blood and balance the minerals your body runs on, day and night. This view simply shows where those minerals are coming from today — a varied, balanced diet is what keeps the mix steady. (emerging evidence)
- Digestion — Your gut does the daily work of turning food into fuel and keeping things moving comfortably. These nutrients support a smooth, regular rhythm and a healthy gut lining. (established evidence)
- Bones — Bone is living tissue that's always being renewed, drawing on these nutrients to stay dense and strong. Supporting them now helps your body maintain a sturdy frame for years to come. (established evidence)
- Reproductive — Hormone balance and steady energy underpin a healthy reproductive system. These nutrients support your body's normal function in this area, especially when life has left you depleted. (emerging evidence)
- Heart — Your heart beats around a hundred thousand times a day, and these nutrients support the rhythm and the healthy blood flow behind it. They help your body maintain circulation you don't have to think about. (emerging evidence)
Goals it supports
- Hydration (emerging evidence)
- Better sleep (emerging evidence)
- Energy & stamina (emerging evidence)
- Muscle building (emerging evidence)
- Stress reduction (emerging evidence)
- Athletic performance (emerging evidence)
- General wellness (established evidence)
- Muscle & recovery (emerging evidence)
- Cycle support (emerging evidence)
- Mood support (emerging evidence)
Frequently asked questions
How much Magnesium do adult women need per day?
Adult women (19–50) need 310 mg of Magnesium per day, per NIH/NASEM Dietary Reference Intakes.
How much Magnesium do adult men need per day?
Adult men (19–50) need 400 mg of Magnesium per day, per NIH/NASEM Dietary Reference Intakes.
Does pregnancy change how much Magnesium you need?
Yes — during pregnancy (ages 19–50) the recommended amount rises to 350 mg per day, compared with 310 mg for non-pregnant adult women.
Is there an upper limit for Magnesium?
Yes — for adults 19–50, the tolerable upper limit is 350 mg. High supplemental magnesium can cause diarrhea, nausea, and abdominal cramping. Magnesium from food doesn't count toward this limit.
What foods are highest in Magnesium?
Good sources include Pumpkin and chia seeds, Almonds and cashews, Spinach, Black beans, and Dark chocolate.
How Tavita handles this
Tavita logs Magnesium from both the food you eat and the supplements you take, adding both into one running daily total. It warns you before you reach the tolerable upper limit, counting only what comes from supplements, since that's what this particular limit is defined against.
Sources
Figures on this page come from the NIH Office of Dietary Supplements fact sheets and the National Academies of Sciences, Engineering, and Medicine (NASEM) Dietary Reference Intake tables — the same dataset that powers the Tavita app. They were independently re-verified by blind re-derivation on August 9, 2026. See the methodology page for how this library is built and kept current.
Tavita is not a medical provider. This page is educational information, not medical advice — talk to your clinician before changing your supplement or medication routine.