Vitamin D3, often just referred to as vitamin D, is a vital nutrient that our bodies need for a plethora of reasons. Whether it’s bolstering our immune system, keeping our bones strong, or helping our bodies absorb calcium, it’s safe to say that Vitamin D3 has a significant role to play. However, in this blog post, I am not merely going to reiterate the importance of Vitamin D3 – something that has already been discussed in plenty of articles and forums.

The area I am more interested in shedding light on pertains to the current recommended daily intake of vitamin D3. Many researchers, medical experts, and nutritionists have started to question whether these recommendations are substantially underestimated. Could it be that we should, in fact, be consuming more Vitamin D3? But the question then arises – how much more?

The issue is complicated by the fact that Vitamin D3 is fat-soluble, meaning it can accumulate in the body over time. This brings in a very legitimate concern: could prolonged increased intake lead to harmful effects by exceeding safe levels? I decided to put this to the test – a personal experiment of sorts.

I began taking 5000 International Units (IU) of Vitamin D3 daily in February of this year, continuing this regimen for four months. Regular tests were part of the plan, and so, I got my venous blood levels checked three times during this period – at the start, midway, and towards the end.

After four solid months of this consistent regimen, my vitamin D3 levels in the blood increased from 33 to just 38 ng/ml. To put things in perspective, the normal range for vitamin D3 levels in the body falls between 30 to 50 or 100 ng/ml. The slight increase was indeed surprising and at the same time eye-opening.

The U.S. National Institutes of Health (NIH) provides the following ranges for blood levels of 25(OH)D:

  • Deficiency: less than 12 ng/mL
  • Insufficiency (some think this is too low): 12 to 20 ng/mL
  • Generally adequate for bone and overall health: 20 to 50 ng/mL
  • Possibly too high: greater than 50 ng/mL
  • Potentially harmful: greater than 125 ng/mL

These values can vary slightly between different sources and countries. For instance, some health professionals recommend levels closer to the higher end of the sufficient range, particularly for individuals at risk of osteoporosis or certain other health conditions.

The commonly accepted ranges in Europe are:

  • Deficiency: Less than 20 ng/mL
  • Insufficient: 20-29 ng/mL
  • Sufficient: 30-100 ng/mL
  • Potential Harm: More than 100 ng/mL

Clearly, I’m still far from reaching the upper limit of the normal range, despite having increased my Vitamin D3 intake for several months.

From this personal experiment, I am now inclined to believe that an increase in intake to 10,000 IU of Vitamin D3 per day may indeed be feasible, safe and potentially beneficial.

It’s important to remember that while Vitamin D3 can be obtained from certain foods like fatty fish and fortified dairy products, the most efficient source is sunlight. However, with modern indoor lifestyles and colder climates, it’s not always easy to get enough sunshine exposure. Supplements, therefore, become a viable and necessary source for many.

Keep in mind that vitamin D does not interact well with vitamin E, yet it works synergistically with both calcium and phosphorus.

Moreover, in addition to monitoring the quantity, it’s equally essential to focus on the quality of supplements. Always opt for reputable brands and pay attention to any other ingredients included in the supplement.

While more research is needed to definitively establish the optimal dosage for Vitamin D3, it seems that the current daily recommendations may indeed be too low. It will be interesting to see how this narrative evolves as more research comes to light. Until then, stay healthy, get your sunshine, or if you’re like me, experiment a bit with your Vitamin D3 intake.


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