Re: Vitamin D Supplement
But it doesn't matter how a mother gets her vitamin D, through sunlight exposure on the skin or through a supplement. While a small amount of vitamin D is transferred through through breast milk when a mother has adequate levels, it is not even close to sufficient for an infant. Even when the mother takes a very high dose supplement (6400 IU/d, far above recommended, and proven safe in the long term, doses at 1,000-2,000 IU/d) the levels present in her milk do not provide adequate vitamin D to her infant.
Originally Posted by @llli*djs.mom
My point is that infants are built to get vitamin D through sunlight exposure on their skin, not through breast milk.
Through the bulk of human history, mothers would have young infants outside in the sun. Thus, there was never a need for vitamin D to pass through breast milk very well - so it doesn't. Nor was there ever any need for it to be absorbed more easily by the infant, as the forms of vitamin D presenting breast milk are the same as the forms in supplements, which are different and less efficacious as the form produced by photosynthesis. But our lifestyles have changed and we hide from the sun now, so our infants no longer have the natural source of vitamin D and we wind up with deficiency.
The only solutions are: 1, Get the infant out in the sun, dressed appropriately and for adequate periods of time. 2, Supplement the infant. 3, And (possibly) supplement the mother with extremely high doses of vitamin D3 (this one is risky though as it has not been proven safe or effective at this point).
The PP stated:
And while this is true for other vitamins, minerals, and other compounds which our physiology is "designed" to obtain from dietary sources, vitamin D is much different from these other materials as our physiology is not "designed" to obtain it from dietary sources. Furthermore, as far as I know there is no evidence that shows this to be true. Even if it is true, vitamin D in breast milk does not occur in sufficient quantities to support an infant. The infant needs sunlight exposure. Which she states:
Originally Posted by @llli*raejoy
And I agree with this second part (although I believe the recommendation is also exposure on the face, neck, abdomen or back) for certain individuals living in certain climates. Latitude effects the amount of incoming solar radiation, so just because it is nice and sunny it does not mean that you are able to get adequate vitamin D from sunlight alone depending on your skin tone in such a short time.
Originally Posted by @llli*raejoy
Anyway, I think the danger here is to assume that our infants are "designed" to get vitamin D from our milk. Or that our milk is "designed" to provide vitamin D to our infants. Neither of these things are true. Infants are "designed" to get vitamin D from the sun just like everyone else. As such, as long as an infant gets enough sun exposure w.r.t skin tone, then that infant will get adequate vitamin D. If not then a supplement is needed.
Because of the deficiency and insufficiency rates in the US and around the world, it is clear that many infants are not getting enough sunlight exposure which is why supplements are recommended. Doctors are rarely going to recommend sunlight exposure because it is difficult to quantify how much is needed and for liability reasons (i.e. melanoma).
K. Sophia - Mama to my little lactivore, the amazing Mr. X (11/10).