Privet devochki! Ya tut vse na temu vitamina D razmyshlyala i napisala svoej amirikanskoj rodstvennice. Ona u menya glav. vrach v samoj bol'shoj bol'nice v Mehjne i ochen' dobryj chelovek. Ya tozhe vrode ne zloj, poehtomu delyus' ee sovetom, vdrug ehta tema tut tozhe kogo-to volnuet. Hello Svetlana,Quite honestly - the ONLY way you will know for sure is to take a vitamin D 25OH blood level which would require little anna to have a blood draw.  I do NOT think that is necessary and my recommendation is at the bottom of this letter.  BUT... here is a little guide to go by so you can rest assured that you know what you are talking about! 1.  A smart interactive Mom's intuition for her own baby far outweighs a general recommendation for the public2.  What is recommended are general recommendations determined to protect the masses - and NOT the individual3.  Vit D supplementation is highly recommended for breast fed babies here in the U.S. at 400 IU / (or 10 mcg) per day.  Breast milk is dependent on mom's Vit D status.  If mom supplements with 2000IU of vit D3 per day - the baby has been shown to have adequate Vit D3 status equivalent to taking 400IU / day in the breast milk by virtue of mom taking supplementation.4.  If you are formula feeding your baby, which you are, 32 ounces of formula per day should have the right amount of Vit D for Anna, and supplementation should not be necessary.  By the time a baby is 4 months, they are generally drinking 32 ounces of formula a day5.  Vitamin D3 comes in two forms:  1.  Ergocalciferol - which is actually Vit D2 and 2.  Cholecalciferol which is Vit D3.  Prescriptions are Vit D2 - and NOT good for your baby (or you.)  Supplements should always be Vit D3 6.  Regarding sun exposure:  here is a good guide to go by that i give to my baby's parents:Sunlight exposure needed to achieve adequate vitamin D status*Infant Group	Clothing	Minutes/Week	Average Minutes/Day	ReferenceCaucasian infants,0-6 months old,latitude 39°9′N,Cincinnati, Ohio, USA	fully clothed without a hat	120 min/wk(2 hours)	17.1 min/day	Specker 1985diaper only	30 min/wk(1/2 hour)	4.3 min/dayChinese infants,1-8 months old,latitude 39°55′N,Beijing, China	fully clothed without a hat	168 min/wk(2 hrs, 48 min)	24 min/day	Ho 1985* In these studies, this was defined as the amount of sunlight exposure necessary to maintain blood serum concentrations of 25-hydroxyvitamin D at a level above the lower limit of the normal range (11 ng/ml).7.  YOUR vitamin D status while you were pregnant laid down the foundation stores of Anna's.  If you were well supplied yourself, anna's stores at birth will be good.  If you were deficient, she will need standard replacement.  The recommendations are based on the average mother being fairly deficient of Vit D.  This may not be the case with you - so consider your OWN levels as well.  8.  The SKIN is the primary organ to obtain and convert sunlight into Vitamin D3.  Most people are frightened of skin cancer - unnecessarily.  All things in extreme are bad.  but as you can see in the above graph, 4.3 min / day in a diaper or 17.1 min / day fully clothed without a hat is sufficient - and this will NOT result in sun burn - and will provide the healthiest form of Vit D3What i think I am hearing is that you are suspicious that your baby does not need supplemental Vit D.  She appears to be reacting to additional Vit D - or it seems like an association.  I believe if you follow the above guidelines, check the Vit D supplement that you are using for additives such as sweeteners and chemicals that are not natural, and use only natural products, and monitor closely - Anna will be better off REGARDLESS of what your pediatrician says.You are welcome to write me anytime.I am happy to help.Love karen