Thursday, May 13, 2010

Vitamin C stops your red blood cells exploding - have to supplement to obtain the level of vitamin C needed

When cells die they "explode" or more scientifically their membrane (think "cell skin") breaks down and either crumples or gets messy and is opened up, but explode sounds so much cooler. Cell death is a normal part of your body function. However logic implies that cells dieing because they are under stress is not a good idea. This stress can be caused by removal of food (glucose) or by oxidative stress.

Red blood cells also undergo cell death when they are under stresses. Turns out, rather unsurprisingly, that vitamin C prevents this cell death from occurring. The vitamin C level tested was 0.28mM. Now the question that I have is how much is this level in reality. So my ruff calculations say this is 250mg of vitamin C in your blood (assuming your an "average" adult). [4.7 liters of blood, and molecular weight vitamin C is 176]

So this still doesn't tell you what you need to eat to obtain this level. Well it turns out that the average adult has in their body:
1.2–2.0 g of ascorbic acid that may be maintained with 75 mg/d of ascorbic acid
A turn over of 1 mg/kg body and a body pool of 22 mg/kg at plasma ascorbate concentration of 50 μmol/ L
So a typical adult weights 100 kg (to make the numbers easy). Therefore their body pool would need to be 2200 mg of vitamin C with 100 mg a day ingestion. Now the level of vitamin C that stopped red blood cell death was 0.28mM which is 280 μmol/ L. So ingesting 100 mg a day (or 22mg per kg of body weight) obtains a plasma (blood) level of 50 μmol/ L. However 280, which is the level we want, is 5.6 times higher than 50!

Therefore one could assume that 100 mg a day of vitamin C times by 5.6 would give the blood levels of 280 μmol/ L. The level of vitamin C ingestion would then be 560 mg.

Now I am not convinced that such a simple linear multiplication is appropriate. It is likely that like nearly everything in the body that there is some non linear effect. Thus instead of multiplying by 5.6 it is almost certain that it should be a higher number. However what I am unsure of factor should be used.

560 mg of vitamin C - according to the food tables (which I am highly suspicious of) the average weight of a kiwifruit is  40 g. And they have 90 mg / 100 grams of vitamin C. Therefore you need to eat 15 kiwifruit or you could go for 7 and 1/2 oranges...... maybe I will also take some vitamin C supplements as well. 

References: Hasan Mahmuda, Syed M. Qadria, Michael Föllera, Florian Lang  Inhibition of suicidal erythrocyte death by vitamin C. Nutrition Volume 26, Issue 6, June 2010, Pages 671-676

K Akhilender Naidu Vitamin C in human health and disease is still a mystery ? An overview Nutrition Journal 2003, 2:7doi:10.1186/1475-2891-2-7

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