Not quite – the manufacturer recommends taking 1 drop every other day, not every day. This means your average daily intake is actually closer to 2000 IU, even though a single drop contains 4000 IU. This is what's known as bolus dosing, where the body receives a larger single dose that is then distributed over two days, rather than an even daily intake. If you want to achieve a higher average daily intake, consult your doctor or pharmacist about more frequent dosing, since this would already be approaching doses near the upper safe limit of 4000 IU/day (NIH ODS, 2024).

Vitamin D3 is a fat-soluble vitamin, meaning it is better absorbed when dissolved in fat or consumed together with dietary fats. Research has shown that taking vitamin D3 with a fat-containing meal can increase its plasma concentration by up to approximately 32% compared to a fat-free meal (Dawson-Hughes et al., 2015). The sunflower oil in these drops therefore isn't just a carrier for easier dosing, but also supports the absorption of the active ingredient itself.

No, according to the ingredient information, the vitamin D3 (cholecalciferol) in this product is derived from lanolin, i.e. sheep's wool, meaning the product is not suitable for strict vegans. If you're looking for a vegan version of vitamin D, there is also vitamin D2 (ergocalciferol), which is always plant-derived, though evidence suggests it is less effective at raising and maintaining blood levels of 25-hydroxyvitamin D compared to D3 (Tripkovic et al., 2012). If the source matters to you, be sure to check other products in our range as well.

The manufacturer itself recommends monitoring your blood vitamin D level (25(OH)D) if using the product over several months, and advises against combining it with other sources of vitamin D, which is a sensible precaution. Generally speaking, 4000 IU per day is the upper safe limit for standalone daily supplementation in adults (NIH ODS, 2024; EFSA, 2023), but since this product is taken every other day, the average daily intake is below this limit. Nevertheless, we recommend checking your vitamin D status with a lab test for long-term use (several months) and consulting a doctor if needed.