T Nation

Milk & Hypercalcemia/Vitamin D Overdose


#1

The milk we have here (I don't live in the US) has 150% of daily recommended value of calcium and 100% daily recommended value of vitamin D, in one litre (which I believe, is about a quart, 1/4 a gallon anyway). Now, I talked with my father (who's a pharmacist) about this, and he said that if one drinks a lot of milk, there's risk of hypercalcemia and vitamin D overdose. I used to try to drink a lot of milk (2 litres or so a day), that's where our conversation came from.

Now, I know my father knows his field, but at the same time, I know he's very conservative about nutrition, e.g. giving me shit for eating too much eggs (though my cholesterol levels are very good).

As a sidenote, don't know if it matters, but I drink milk that's low in lactose, because I have lactose intolerance (not diagnosed but the symptoms are there).
What are your thoughts on milk consumption and calcium/vitamin D levels?


#2

L-Dizzle, Vitamin D defficeny is seen in the majority of the population at higher latitudes.

Also, do you drink Skim Milk? I always wondered how bioavailable the Vit D is in it due to the lack of fat. Obviously having the milk w/ something else that it high in fat

Secondly, I have read once that in hot climates w/ plenty of sun exposure humans will synthesize 15,000-25,000IU's PER DAY. I believe Dr. Weil brought this up in one of his books (he is big on people have chronic Vitamin D deficencies). The minimuim amount of Vitamin D reccomended by most nutritionist is 1000IU's per day.


#3

Yes, I drink skim milk. But I also consume quite a lot of fat, mostly from olive oil, for what it's worth.
My father did in fact talk about the bioavailability factor, being that vitamin D, along with A, E and K, are fat-soluble.

I don't know the international unit/gram conversion for any vitamin, and don't know how the RDAs vary from country to country, but I've read that the RDA for vitamin D is 800mg...

I have also read about vitamin D deficiencies. I live in Finland where it gets very dark during winter times, and i'm also dark skinned, so my body can't synthesize as much vitamin D as a light individual's even when the does shine.


#4

The recomended amount of vitamin D is 400 I.U. per day. I consume a gallon of milk every day and a multi-vitamin with minerals every day. This works out to 5 times the daily recommended amount. From those two, I get 2,000 I.U. per day. "Vitamin D toxicity is reported to occur after the ingestion of greater than 50,000 I.U. daily for several years."
see:
Effects of vitamin D overdose
By Razak Lajis

http://www.prn2.usm.my/mainsite/bulletin/sun/1996/sun44.html

Calcium has some conflicting information and as best as I can tell no one knows what the limits should be. There is also conflicting information about kidney stones and calcium.


#5

For starters Calcium isn't particularly absorbable and like most things how it got in your body, be it through food, supplements and in what form is an important factor. Calcium is constantly being turned over by bone intestines nad renal system.

The transport of calcium itself is controlled by three hormones, parathyroid hormone, calcitonin and a metabolite of vitamin D called 1,25 dihydroxyvitamin D which is basically why you need vitamin D in Calcium synthesis and general homeostatis.

When you ingest some Calcium be it a present in a some milk or if you eat a piece if chalk, the Vitamin D metabolite governs the rate of absorption from the intestines.

As a general rule, in food form, and possibly without some hi-tech supplement if you ingest about 1000mg of calcium a day, you will absorb about 350mg from intestine to extracellular fluid. Then part of this (about 150-200mg) is lost back through enteric secretion into the gut. Your total absoroption of calcium is therefore as little as 150mg from that whole 1000mg you ingested.

In normal circadian calcium homeostatis (i.e. what happens with calcium in a day) about 500-600mg is exchanged between bone (the principle storage point for calcium) and bodily fluids. The total bone 'resevoir' of calicum is about 500 to 1500 mg with about 1000mg on average in adults.

When you are growing up, particularly in young children and during puberty absorption is higher than the figures I offerd above. Similarly those with defficiencies when suddenly taking in more calcium will have higher absoroption levels. One thing is for sure, you need Vitamin D to absorb Calcium.

My main point is its quite hard to overdose on Calcium and there are regulatory mechanisms governing absorption. The initial indicators of calcium levels being too high are constipation.

As far as Vitamin D goes, besides being involved in Calcium turnover it is also stimulates phosphate and magnesium aborption from the intestine. In Magnesium the vitamin Pyridoxine (B6) is also required for absorption.

Depending on your exposure to sunlight and skin type, cholecalciferol (type Vit D) will be manufactured by the skin when it is exposed to sunshine. Its unlikely to cause an overdose with excessive sunlight, and the same goes for dietary amounts even if you are eating calcium rich foods. I would not take a direct Vit D supplement.

Vit D overdose initially causes vomiting, nausea and a metallic taste in the mouth and also fatigue. Recorded cases of vit D overdose stem from supplements and not from foodstuffs as there is regulation to absorption as in Calcium.


#6

Thanks for taking the time to reply guys, I'll probably re-consider my approach to milk. I use to take a multivitamin supplement, dont take it anymore though. It didn't have any fat-soluble vitamins but had, I believe, 12,5% of RDA of calcium.
Me being lactose intolerant, my milk costs slightly more than regular milk, so in that regard, I won't probably drink more than 2 litres (half a gallon) a day.