Starting today, I will be reviewing the most important papers each month (in my opinion) from the American Journal of Clinical Nutrition . The first issue, Volume 85, Number 1, has a number of excellent studies.
Risk Assessment for vitamin D by Hathcock, Shao, Vieth, and Heaney – In this review article, the authors believe that vitamin D is much safer than previously thought. While high doses are dangerous, 800 I.U.’s daily for adults and 400 for children seem to be safe (higher levels were deemed safe but I like to keep things a little saner).
Normal-weight obese syndrome: early inflammation? by De Lorenzo, et al – The authors of this study propose that people with normal weight but high fat content (>30%) are at a higher risk of becoming obese than those with lower fat levels. They further report that adipose tissue (fat tissue) harbors more pro-inflammatory cytokeines which leads to a greater risk of being obese later in life. This seemingly makes the case that an increase in exercise and a lowering of body fat is protective against obesity especially among younger people.
Supplementation with calcium + vitamin D enhances the beneficial effect of weight loss on plasma lipid and lipoprotein concentrations by Major, et al – When going on a weight loss program, the addition of calcium and vitamin D helps to improve your lipid profile (cholesterol, HDL and LDL).
Folate and vitamin B-12 status in relation to anemia, macrocytosis, and cognitive impairment in older Americans in the age of folic acid fortification by Morris, Jacques, Rosenberg and Selhub – This excellent study shows that when vitamin B-12 is deficient, high folic acid was associated with anemia and cognitive impairment. When B-12 was normal, folic acid was associated with protection against cognitive impairment. This means that a balance between the two nutrients is as important as having enough of either one. Two assess your levels of these two nutrients, I suggest a urine Organix test from MetaMetrix . The two markers are FIGLU (folic acid marker) and Methylmalonate (B-12).
Carbohydrate intake and HDL in a multiethnic population by Merchant, et al – Basically, the bottom line of this study was the suggestion that decreasing the intake of sugar-containing soft drinks and juices as well as snacks would be highly beneficial to improving you blood fat profile.
Given Heaney in Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol1shows Healthy men seem to use 3000–5000 IU cholecalciferol/d why do you consider using only a fifth of your daily requirement sensible?
It would surely be insane to think, if your your bank account were in the red while you continue spending $4000/d, that paying $800/d into that account will clear the deficit?
When you read the entire study, it suggests that the tissue stores 25(OH)D and that during winter months, this is released to keep a homeostatic quantity circulating. Also, the authors further suggest that there are diminishing returns with higher doses.
Now I do agree that people may need higher doses of vitamin D if they don’t get enough sunlight in the spring, summer and fall but whenever you focus on one particular nutrient you run the risk of imbalancing the system which I believe is a far greater threat than a minor deficiency.
Using your corollary, in the summer, we are paying $6,000/d into our account while we spend $4,000/d. If we try to keep up in the winter by adding a lot of vitamin D, in the summer time we may be causing our bank to overflow with unknown consequences.
The authors in the paper you cite do state that the tolerable upper limit of 2000 IU/d is too low and I agree. Still, we do need to do much more research into the value of this essential nutrient.
Thanks for the great comment.