Can You Take Vitamin D and Iron Together?

Vitamin D and iron are essential nutrients that must be consumed daily to ensure adequate amounts. Vitamin D is critical for bone health, immune function, mood, and more, while iron is involved in hematopoiesis, immune function, and energy production.

A deficiency of either can interfere with several biochemical processes in the body. However, if you’re following a plant-based diet that doesn’t provide sufficient amounts, supplementation is the best way to ensure you meet your daily requirements.

While you commonly see vitamin D and iron combined in a multivitamin, is it safe to take them together? We’re looking into the research and giving you everything you need to know about potential vitamin D and iron interactions.

The Importance Of Getting Enough Iron

When it comes to daily nutrient supplementation, most people don’t think twice about iron. It’s relatively easy to obtain from food, so what’s the need to supplement? We’ll talk about why iron supplements are recommended for specific populations in a minute, but first, let’s look at why you need iron.

Dietary iron comes in two forms: heme iron and non-heme iron ¹. Heme iron is found only in food of animal origin, especially red meat, and has good bioavailability, while non-heme iron is native to plant foods and is much less bioavailable due to other compounds naturally present in plants (lectins, oxalates, phytates, etc.).

Iron is found in the highest concentrations in red meat as hemoglobin and myoglobin, where it’s released from the flesh after being acted on by proteolytic enzymes in the stomach and small intestine ¹.

Once metabolized, iron is absorbed and sent to the bone marrow for hemoglobin synthesis, while a small amount is stored in the liver.

The most notable role of iron is in hemoglobin synthesis for red blood cell production, but it’s also required for ^{2, 3}:

• Immune function
• Energy production
• Body temperature regulation

Too much and too little iron can be dangerous, so ensure you supplement the appropriate amount to maintain iron stores. The RDI for iron is 1.8 times higher for vegetarians and vegans due to the poor bioavailability of non-heme iron ⁴. The requirements also increase for menstruating, pregnant, or lactating women.

What Is Vitamin D And Why Do We Need It?

While getting all the essential nutrients is vital for maintaining health, vitamin D plays an extra special role. It’s classified as a vitamin but functions more like a hormone (prohormone) produced photochemically in the skin from 7-dehydrocholesterol after UVB exposure ⁵.

While we typically talk about the benefits of vitamin D3, D3 doesn’t offer any intrinsic biological activity; it must be metabolized to its active form, 25(OH)D3, in the liver and then to 1α,25(OH)2D3, 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3], before it can be utilized.

Once converted, its primary biological role is as a regulator of calcium homeostasis, but it’s also known to have roles in other areas of the body, including:

• Gastrointestinal tract
• Immune system
• Cardiovascular system
• Muscular system
• Nervous system

These beneficial effects are exerted by regulating gene transcription through the vitamin D receptor (VDR); nearly all cells contain a VDR. Research suggests that vitamin D directly or indirectly controls anywhere from 200 to 2,000 genes ⁶.

And because vitamin D can cross the blood-brain barrier, it also influences brain function, but more research is needed to clarify its roles.

Are Vitamin D And Iron Safe To Take Together?

With that said, we get to the question: can you take vitamin D and iron together? Yes - there have been no reported issues with supplementing iron and vitamin D simultaneously. Research shows that iron is essential in several enzymatic systems, including those needed for vitamin D activation ⁷.

Without getting too complicated, vitamin D is activated by two sequential steps ⁸:

1. 25(OH)D3 is produced in the liver by a type of cytochrome P450 called CYP2R1.
2. The next hydroxylation step happens in the kidneys and specific other tissues by CYP27B1 to produce 1,25(OH)2D3; CYP2R1 requires NADPH-cytochrome P450 reductase to function but also requires two other heme-containing compounds: ferredoxin reductase and ferredoxin.

Based on this, it would seem that vitamin D metabolism depends on iron, and low iron status could interfere with vitamin D activation.

On the other hand, some research suggests that long-term supplementation with iron and high vitamin D levels may interfere with iron absorption ⁹.

How To Fulfill Your Daily Nutrient Needs

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It’s an ultramodern multivitamin designed to unlock your body’s full potential with nature-identical NutriGenesis® vitamins and minerals. They’re bioengineered with cofactors that boost absorption and maximize benefits to provide a state-of-the-art multivitamin for enhanced overall health and performance.

Best of all, four capsules are all you need - take 2 in the morning and 2 in the evening, with or without food. And whenever you need an upgrade to fill nutritional gaps, simply up your dose to 3 in the morning and 3 in the evening. It’s that easy.