Works for me as my skin breaks out when ever I take normal D3 because it is made from lanolin which is sourced from sheep's wool. I have always been reactive to wool. I feel better taking a plant-based product anyway because as you can see I am the Plant-based Grandma and I promote (blog/vlog) about plant-based living for health reasons. Besides it wouldn't be natural to eat wool. As a former nurse and biology teacher and scholar with two Master's degrees I go by what the empirical evidence says. For instance, scientists are now learning about the importance of fiber to feed the good bacteria in your gut to prevent diabetes, heart disease, high blood pressure, obesity just to name a few, I think it is important to eat this way. Plus, animal-product eating gut bugs produce TMAO out of carnitine and lecithin. This chemical is responsible for depositing cholesterol in your arteries. By the way, taking a TMAO test is the greatest predictor of death and cardiovascular events out there; way above taking your cholesterol or any other test. And that is not the only harmful substance created from meat by the bacteria in your gut. Anyway, I digress (but I thought it was important for you to know this). Being mostly plant-based (with very rare excursions into the dairy and egg world and meat-eating only on holidays), I can't get Vitamin D3 from my diet. Plus I live too far north to get it from the sun in the winter (and I am not so sure that is too healthy to do either). So I must supplement. You can't really get it naturally from foods because any foods which have it are typically fortified with D2. Vitamin D3 is the most bioavailable form of Vitamin D. So I might as well take a pill. I prefer this form to the mushroom form because mushrooms are a fungus and I am still suspicious of fungi due to all I learned from Doug Kaufmann on Know the Cause. Though, it is probably okay. I trust Doctor's Best as a company because they have Good Manufacturing Practices