I always have a (more common than widely known) reaction to Cholecalciferol ("Regular Vitamin D3") that causes me severe anxiety at doses even as low as 400-1000UI.<br /><br />I've tried taking MK-7 & MK-4 with it, as well as medium and large doses of Magnesium Glycinate and Malate with NO relief of this problem.<br /><br />This supplement with calcifediol does not have this side-effect for me. Calcifediol bypasses the conversion by the liver and is one step closer to Calcitrol, the next step to the final form of D3 usable by the body (25-hydroxy). It also skips the requirement of adequate Magnesium levels.<br /><br />If you have this more and more common D3 response of anxiety, give this form a try.

I was deficient in Vitamin D (26 on 8/2021), but never had success with other brands (anxiety / stomach ache). I have also never had my levels tested so didn't know I was deficient. Took the plunge on this brand and wow - had my levels retested on 10/2021 and had moved from 26 to 74! I can feel the difference and no side effects. Worked so well for me!

I just got done filling up my supplement containers for the next month, and I'm frustrated enough to write a review about how AWFUL the product packaging is on these. The foil is too thick to pierce easily with my fingernail or with the tablet, so I have to first slit the foil with a steak knive on every tablet. Then, I still have to wrestle with the hard plastic backing to get the tiny pill out through the foil one by one. My index finger is left hurting, and I usually have to pick about every fifth one off the floor after it goes flying. If I were a person who is elderly or who had arthritis and dexterity issues, there is no way I would be able to mess with all of these problems. I keep taking them because the supplement itself does work amazingly well (where others have failed to raise my serum D3 levels), but this makes me so upset every time I need to deal with the ridiculous packaging.

I suffer from Vitamin D intoxication when I consume 800IU &lt; of Vitamin D. This product has been of great help in helping me raise my Vitamin D levels.<br /><br />I've noticed this product doesn't provide the anti-anxiety benefits that is normally accompanied with Vitamin D3 supplementation.<br /><br />Update: I had to stop taking this supplement after 21 days because it gave me horrible insomnia. Went back to taking 800IU of Vitamin D3.<br /><br />Update2: Figured out what was causing my Vitamin D intolerance issues. Consuming Vitamin A (preferably from animal liver) with my Vitamin D3 basically makes it so I don't get any side effects. No insomnia, brain fog, etc. According to my research, a small amount of Retinol (Vitamin A) is required for Vitamin D metabolism.

Ever since bariatric surgery, I've had a hard time keeping my Vit D levels up - even with mega doses of 50,000 dry vitamin D every day. I went as high as 250K per day and they barely budged. I've been using d.velop for about 7 months now and my D levels have increased from 35 to 62 (30-100 scale). As a consequence, my PTH has dropped 25 points (which is good because prolonged high PTH can lead to osteoporosis).<br /><br />This works because my gut no longer absorbs much Vit D, but the form of D in d.velop doesn't need much processing by the gut. It goes straight into he bloodstream instead of being excreeted like other forms of D.<br /><br />This is a great product!

I recently went to my PCP and he stated that my D levels were low. I decided to try this because every other supplement I have tried had either no effect or made me terribly anxious. This worked rather quickly. Within two weeks I feel significantly better woth more energy and less depression. This is a winner for me.