{"id":6258,"date":"2026-04-21T15:34:00","date_gmt":"2026-04-21T14:34:00","guid":{"rendered":"https:\/\/vitalstoday.com\/?p=6258"},"modified":"2026-04-23T08:47:43","modified_gmt":"2026-04-23T07:47:43","slug":"how-to-choose-which-vitamin-d-supplement-to-take","status":"publish","type":"post","link":"https:\/\/vitalstoday.com\/en\/salud\/como-elegir-que-suplemento-de-vitamina-d-tomar\/","title":{"rendered":"How to choose which vitamin D supplement to take?"},"content":{"rendered":"

When choosing a vitamin D supplement, the dosage and format are usually more important than the brand. For self-care purchases, there are three key factors. D3 generally performs better than D2, the NRV (Nutrient Reference Value) on the packaging falls short as a practical guide, and very high doses are in a different category altogether.<\/p>\n\n\n\n

Vitamin D2 or D3?<\/h2>\n\n\n\n\n\n<\/p>\n

On labels you will mostly see two forms. Vitamin D2, also called ergocalciferol, is usually linked to plant or fungal sources. Vitamin D3, or cholecalciferol<\/a>, is the form the body makes with sun exposure and it usually comes from lanolin, although there are also options derived from lichens.<\/p>\n

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The difference isn't that D2 is useless. Both forms can raise vitamin D levels, but D3 usually does it better and maintains them longer, so it's the one most often requested when someone is looking for a general supplement.<\/p>\n\n\n\n

What do IU, micrograms, and NRV mean?<\/h2>\n\n\n\n

Vitamin D supplements are usually expressed in IU or micrograms. The conversion is simple. One microgram is equivalent to 40 IU, so 10 \u00b5g is 400 IU, 25 \u00b5g is 1000 IU, and 100 \u00b5g is 4000 IU.<\/p>\n\n\n\n\n\n<\/p>\n

The main confusion usually starts with the NRV<\/a>. For vitamin D, European labelling still uses 5 \u00b5g as the reference value, so a product with 100 \u00b5g can show 2000% of the NRV and look much more extreme than it really is.<\/p>\n

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EFSA<\/a> sets an adequate intake of 600 IU (15 \u00b5g) per day when skin synthesis is minimal. The NHS<\/a> uses 400 IU (10 \u00b5g) as a general reference in autumn and winter, and the NIH<\/a> in the United States uses 600 IU (15 \u00b5g) for adults aged 19 to 70 and 800 IU (20 \u00b5g) from age 71 onwards. That is why the NRV on the label is better read as a labelling reference, not as the full guide.<\/p>\n

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What changes between 400, 1000 and 4000 IU?<\/h2>\n\n\n\n

If you see 400 IU, you're looking at a strength that aligns with the low maintenance base mentioned in several public recommendations. 1000 IU already represents a price above that floor and is generally more appealing to those seeking a mid-range daily option, for example, if they spend little time outdoors or are looking for a more stable investment for the colder months.<\/p>\n\n\n\n

The 4000 IU dose falls into a different category. Both the EFSA and the NIH set 100 \u00b5g or 4000 IU as the tolerable upper daily limit for adults, so it's not the most neutral option for routine purchases. It's more commonly seen in people with different circumstances, such as low sun exposure, dark skin, advanced age, obesity, or absorption problems.<\/p>\n\n\n\n

That doesn't mean the highest dose is automatically the best. Sun exposure, season, age, skin tone, and the reason for using the product all significantly affect how the packaging is interpreted.<\/p>\n\n\n<\/p>\n

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Basic D3 400 IU<\/p>\n

\n Solaray<\/span> vitamin D3 400 IU (10 \u00b5g) 120 pearls<\/a><\/p>\n<\/div>\n

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\n\"Solaray
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11,94 \u20ac<\/p>\n<\/div>\n

\n View in Naturitas<\/span><\/a><\/div>\n<\/div>\n
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Why it might fit<\/p>\n