16

Breakdown of the claims There are a couple of claims contained together in this question. Vitamin D is formed on the skin (as well as in). Relatively large amounts remain on the skin or are secreted immediately from sun-sexposure onto the skin. In both cases the vitamins need an up to 48h waiting period to be (re-)absorbed by the body/skin. That washing ...


13

This is a complex issue. What the public health authorities are saying is correct. Vitamin supplements have health benefits for certain groups of people in certain instances and there are many studies to show this. Vitamin D and Calcium are often recommended for people at risk of osteoporosis. Some people may have digestive disorders for example that also ...


7

I would not worry. Most vitamins are very stable. Vitamin C can oxidize, a little, over about a week, but overall vitamins are retained in large percentages, over months, even at room temperature. More in particular, your question is very wide so I will only give a general answer based on this USAID study, but there are different reasons why vitamins ...


7

No. After this extremely short tl;dr: to be fair, we do not know for sure. Because it seems to be quite complex, if not complicated. And that means the claim is at least very dubious. 25 years ago Vitamin K metabolism would have only considered K1 (phylloquinone) and discuss its role in haemostasis. That has changed and the other derivates are now under ...


5

Possibly, but not likely There is an older study mentioned in this 1985 Chicago Tribune article that states that and extremely high dose of Vitamin C followed by eating shrimp may result in "trivalent arsenic" being converted from the compounds in shrimp. "What the Illinois researchers found is that high doses of vitamin C convert the pentavalent compounds ...


4

Yes. Many studies show the evolution of vitamin in milk while heating. You may even compare heating methods. In this article, the evolution of B12 vitamin is drawn (figure 1). However, the loss of vitamin that occurs while heating the milk up to 100°C is only around 10% of the total B12 vitamin. Prolongated heating will really lower the concentration ...


2

"According to Dr. Rath" reminded me of Linus Pauling and Matthias Rath's unified theory. Matthias Rath (born 1955 in Stuttgart, Germany) is a controversial doctor, businessman, and vitamin salesman. Linus Pauling (February 28, 1901 – August 19, 1994) was one of the most influential chemists in history and ranks among the most important scientists of the ...


1

According @Sklivvz' reference, vitamin C is typically the least stable vitamin. I found a Study on the Kinetics of Vitamin C Degradation in Fresh Strawberry Juices that reports halflife for storage at 8 °C of 4:47 and 5:36 h for juice prepared without and with additional sugar, respectively - I assume that the former number is more relevant for people ...


1

The work of Nakahara et al. concerning vitamins L1 and L2 being essential for lactation is considered refuted in the sense that others found multiple generations could be bred living on diets that are deficient of vitamins L1 and L2. See Milk: the Mammary Gland and Its Secretion, volume II at page 171 which cites to the following article as an example: ...


1

Emblica officinalis (of the family Euphorbiaceae) also known as Indian gooseberry in the form of fruits contain mostly carbohydrate with moderate fiber content and are rich in vitamin C, with some other unique bioactives. Emblica officinalis extract is Generally Recognized As Safe as a food additive by FDA. The effects listed below were noted in ...


1

Vitamin D supplementation at the level of 800 IU per day does not appear to be an effective treatment for Seasonal Affective Disorder in older women. "Winter depression" is properly known as "Seasonal Affective Disorder" (SAD) or "major recurrent depressive disorder with seasonal pattern". As the name suggests, it's recurrent depression that occurs and ...


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