Magnesium, a vital mineral abundant in the human body, plays a crucial role in numerous physiological functions. It’s naturally present in a variety of foods, added to certain food products, and available as a dietary supplement. Understanding “What Foods Magnesium Is Found In” is essential for maintaining optimal health.
The Importance of Magnesium
Magnesium acts as a cofactor in over 300 enzyme systems that regulate diverse biochemical reactions, including:
- Protein synthesis
- Muscle and nerve function
- Blood glucose control
- Blood pressure regulation
It’s also crucial for energy production, oxidative phosphorylation, glycolysis, bone development, and the synthesis of DNA, RNA, and glutathione. Magnesium also facilitates the active transport of calcium and potassium ions across cell membranes, which is critical for nerve impulse conduction, muscle contraction, and maintaining a normal heart rhythm.
An adult body contains approximately 25 grams of magnesium, with the majority stored in bones (50%-60%) and soft tissues. Less than 1% is found in blood serum, and these levels are tightly regulated, typically ranging from 0.75 to 0.95 mmol/L. The kidneys play a key role in magnesium homeostasis by regulating urinary excretion.
Alt: Fresh spinach leaves, showcasing a nutrient-rich vegetable high in magnesium content.
Recommended Dietary Allowances (RDAs) for Magnesium
The Food and Nutrition Board (FNB) at the Institute of Medicine of the National Academies has established Dietary Reference Intakes (DRIs) for magnesium. These values, which vary by age and sex, include the Recommended Dietary Allowance (RDA) which is sufficient to meet the nutrient requirements of nearly all healthy individuals.
The RDAs for magnesium are listed in the table below:
| Age | Male | Female | Pregnancy | Lactation |
|---|---|---|---|---|
| Birth to 6 months | 30 mg* | 30 mg* | ||
| 7–12 months | 75 mg* | 75 mg* | ||
| 1–3 years | 80 mg | 80 mg | ||
| 4–8 years | 130 mg | 130 mg | ||
| 9–13 years | 240 mg | 240 mg | ||
| 14–18 years | 410 mg | 360 mg | 400 mg | 360 mg |
| 19–30 years | 400 mg | 310 mg | 350 mg | 310 mg |
| 31–50 years | 420 mg | 320 mg | 360 mg | 320 mg |
| 51+ years | 420 mg | 320 mg |
*Adequate Intake (AI)
What Foods Magnesium Is Found In: Dietary Sources
Magnesium is abundant in both plant and animal foods. Good sources include:
- Green leafy vegetables (e.g., spinach)
- Legumes
- Nuts (e.g. almonds, cashews)
- Seeds (e.g. pumpkin seeds, chia seeds)
- Whole grains
Generally, foods rich in dietary fiber also contain magnesium. Some breakfast cereals and other foods are also fortified with magnesium. Food processing, especially refining grains, can significantly reduce magnesium content.
Alt: Selection of magnesium-rich nuts and seeds, including almonds, pumpkin seeds, and chia seeds, displayed to highlight their nutritional benefits.
Here are some specific food sources of magnesium and their approximate magnesium content per serving:
| Food | Milligrams (mg) per serving | Percent DV* |
|---|---|---|
| Pumpkin seeds, roasted, 1 ounce | 156 | 37 |
| Chia seeds, 1 ounce | 111 | 26 |
| Almonds, dry roasted, 1 ounce | 80 | 19 |
| Spinach, boiled, ½ cup | 78 | 19 |
| Cashews, dry roasted, 1 ounce | 74 | 18 |
| Peanuts, oil roasted, ¼ cup | 63 | 15 |
| Cereal, shredded wheat, 2 large biscuits | 61 | 15 |
| Soymilk, plain or vanilla, 1 cup | 61 | 15 |
| Black beans, cooked, ½ cup | 60 | 14 |
| Edamame, shelled, cooked, ½ cup | 50 | 12 |
| Peanut butter, smooth, 2 tablespoons | 49 | 12 |
| Potato, baked with skin, 3.5 ounces | 43 | 10 |
| Rice, brown, cooked, ½ cup | 42 | 10 |
| Yogurt, plain, low fat, 8 ounces | 42 | 10 |
| Breakfast cereals, fortified, 1 serving | 42 | 10 |
| Oatmeal, instant, 1 packet | 36 | 9 |
| Kidney beans, canned, ½ cup | 35 | 8 |
| Banana, 1 medium | 32 | 8 |
| Salmon, Atlantic, farmed, cooked, 3 ounces | 26 | 6 |
| Milk, 1 cup | 24–27 | 6 |
| Halibut, cooked, 3 ounces | 24 | 6 |
| Raisins, ½ cup | 23 | 5 |
| Bread, whole wheat, 1 slice | 23 | 5 |
| Avocado, cubed, ½ cup | 22 | 5 |
| Chicken breast, roasted, 3 ounces | 22 | 5 |
| Beef, ground, 90% lean, pan broiled, 3 oz | 20 | 5 |
| Broccoli, chopped and cooked, ½ cup | 12 | 3 |
| Rice, white, cooked, ½ cup | 10 | 2 |
| Apple, 1 medium | 9 | 2 |
| Carrot, raw, 1 medium | 7 | 2 |
*DV = Daily Value (420 mg for adults and children age 4 years and older).
Tap, mineral, and bottled waters can also contribute to magnesium intake, but the amount varies considerably.
Magnesium Supplements
Magnesium supplements are available in various forms, including magnesium oxide, citrate, and chloride. Absorption rates differ among these forms; magnesium that dissolves well in liquid tends to be absorbed more effectively. Studies suggest that magnesium aspartate, citrate, lactate, and chloride are more bioavailable than magnesium oxide and magnesium sulfate.
Potential Health Benefits of Adequate Magnesium Intake
Consuming adequate magnesium through diet and/or supplements may contribute to:
- Reduced risk of hypertension and cardiovascular disease: Some studies suggest a link between higher magnesium intake and lower blood pressure, as well as a reduced risk of sudden cardiac death and ischemic heart disease.
- Lower risk of type 2 diabetes: Magnesium plays a vital role in glucose metabolism, and higher intakes are associated with a decreased risk of diabetes.
- Improved bone health: Magnesium is involved in bone formation and influences key regulators of bone homeostasis.
- Migraine headache prevention: Magnesium deficiency is linked to headache-promoting factors, and supplementation may reduce migraine frequency.
Alt: Various magnesium supplements, including magnesium citrate and magnesium oxide, in capsule and powder form, intended to increase daily magnesium intake.
Risks of Excessive Magnesium Intake
While magnesium from food is generally safe, high doses from supplements or medications can cause diarrhea, nausea, and abdominal cramping. Very large doses of magnesium-containing laxatives and antacids can lead to magnesium toxicity, particularly in individuals with impaired renal function.
The FNB has established Tolerable Upper Intake Levels (ULs) for supplemental magnesium.
| Age | Male | Female | Pregnant | Lactating |
|---|---|---|---|---|
| Birth to 12 months | None established | None established | ||
| 1–3 years | 65 mg | 65 mg | ||
| 4–8 years | 110 mg | 110 mg | ||
| 9–18 years | 350 mg | 350 mg | 350 mg | 350 mg |
| 19+ years | 350 mg | 350 mg | 350 mg | 350 mg |
Interactions with Medications
Magnesium supplements can interact with certain medications, including bisphosphonates, antibiotics, diuretics, and proton pump inhibitors. It’s crucial to discuss magnesium intake with a healthcare provider when taking these or other medications regularly.
Conclusion
Ensuring adequate magnesium intake through a balanced diet rich in magnesium-rich foods is vital for maintaining optimal health. Knowing “what foods magnesium is found in” empowers individuals to make informed dietary choices. While supplements can be helpful in some cases, it’s essential to be mindful of potential risks and interactions with medications. Always consult with a healthcare professional to determine the best approach for your individual needs.
