Bests & Worsts Reviews from Amazon

My vitamin D was very low and my doctor recommended me some high dosage, so I bought this 5000 IU per gel and I started taking 4 of these gels per day(20,000 IU) and 4 months later I did a test to check and there was very little improvement, expecting a good level improvement with (20,000 IU) per day but no. I showed this supplement to the doctor and he said the company made a lot of effort in making sure the label is filled with all the marketing gimmicks(GMP, NON-GMO, 1Yr supply, Organic & etc) but given incomplete information about the ingredient such as where did ‘cholecalciferol’ derived from? The doctor suggested me some brand such as NOW and Carlson and asked me to ensure the ‘cholecalciferol’ is derived from Lanolin. I did bought a NOW Vitamin-D and made sure it’s from Lanolin and took it for 2 months(10,000 IU) per day and then did some bloodwork to check the level. Well the results speak for itself I was way above the optimal range and the doctor recommended me to now simply maintain it with 2,000 IU per day. I will not make judgement on Vita-Optimum products but I will say this, this brand has given me more reasons to doubt their quality than some affordable brands such as NOW and Carlson, whose labels has little marketing gimmicks but complete information about their ingredients, unlike Vita-Optimum’s (Vitamin D-3, 5,000 IU).