Thankyou AnUser, yes it has got confusing and I will try and keep this simple. I posted a link previously which said in part:
Natural vitamin D contains sulfate molecules. Traditionally vitamin D has been made from UVB rays from the sun interacting with cholesterol sulfate within the skin. Scientific study has found that sunlight and cod liver oil have protective effects against CVD. Synthetic vitamin D doesn’t have sulfate molecules, animal studies show the synthetic form can cause damage to arteries.
Evaluating scientific literature comparing the two forms as equals based on labels can been seen as a mistake since the molecular structure of natural vitamin D has sulfate molecules attached and synthetic versions do not, they have different molecular structures and synthetic forms should be more critically evaluated.
Sunlight is the main natural source for vitamin D which has been consistently shown to have cardio-protective effects, lower blood pressure, and help to reduce risk of heart attacks, stroke, and many forms of cancer such as breast cancer.
In a controlled study synthetic vitamin D given to swines showed pathological damage to thoracic aorta in swine consuming the equivalent of 11000 IU of vitamin D3 daily; and lower doses of 2200 IU of D3 daily worsened atherosclerosis in the animals on high fat diets."
John Hemming responded by questioning the credibility of the website but not evaluating the claims. I do not know if the claims are correct but am interested to know if the natural and synthetic forms are actually the same.
I was also concerned by the link I have posted a few times of research stating that a high percentage of vitamins and food fortified with Vitamin D have been found not to accurately state the dosage, and this has even resulted in deaths.
I then discovered that most codliver oil on the market is fortified with synthetic Vit D and so simply assuming the vitamin D in Codliver oil would be present in natural and safe quantities may not be safe.
Being winter where I live I have decided to stick to pate, tinned Codlivers and also take K2.
BobinUK also shared an interesting link about Boron - which I have started to take as well.
I get it that John Hemming assumes everything is okay with supplemental Vit D - but as it has been used to artificially age lab animals (my first post) and the stated dosage may not be accurate I have chosen to risk erring on the side of safety.