A group of researchers has discovered that a group of vitamin D foods, like the popular spinach and green leafy vegetables, contain a vitamin that’s rich in vitamin D.
In the study, published in the journal Science Advances, researchers from the University of Southern California (USC) and the University at Buffalo found that the vitamin D in spinach and other vitamin-d-rich foods like kale and spinach leaves are very high in vitamin A, a precursor to vitamin D, and that the high levels of vitamin A were related to a higher level of vitamin C.
The researchers also found that when the vitamin A in spinach was mixed with vitamin C, the resulting mixture was not only high in calcium but also high in the vitamin C-containing precursor vitamin D3.
This is consistent with previous studies showing that when spinach is mixed with calcium, the result is higher levels of the precursor vitamin-D3.
This research demonstrates that there is a rich supply of vitamin-A in the food we eat and it’s in that supply that the brain synthesizes vitamin D as well.
“This research provides the first evidence that this complex nutrient in spinach is actually able to produce the vitamin-C precursor vitamin.
We now know that this precursor is produced in the brain by the synthesis of a vitamin-like molecule called VDF1.
This will be a crucial step in our understanding of how and why the brain uses vitamin-derived compounds for the production of vitamin and mineral deficiencies,” said study co-author Jodie M. Bower, a professor in the Department of Nutritional Sciences at USC.”
In our research, we were able to identify the VDF precursor, VDF, in spinach.
Our studies also provide new insight into how the brain generates vitamin D and we are learning that VDF is produced by the brain and the brain’s cells in the periphery,” said Bower.
In addition to the vitamin, the researchers found that VAF1, a coenzyme of the vitamin V system, is also found in spinach, and is produced at very low levels.
“Our findings provide the first detailed evidence that VFAs in spinach have the potential to increase the production and utilization of vitamin B12, an essential nutrient in the human diet,” said M. D. Sohi, the senior author of the study.SOHI is a research scientist at the Institute for Nutrition and Human Development, the USC Department of Nutrition.
“Vitamin D-producing foods such as spinach, kale, and spinach leaf contain the same amount of vitamin E, which is thought to be responsible for its vitamin-binding capacity,” said co-senior author Robert S. Schramm, also a professor of nutrition at USC and the Johns Hopkins University School of Public Health.
“While the high-level vitamin D content of spinach may be a useful source of vitamin F, it is likely that this vitamin is only present in spinach because spinach contains a high concentration of vitamin K2, which contributes to the binding capacity of vitamin G to the enzyme VDF.
The vitamin K3 in spinach also contributes to its vitamin D production,” Soh, added.”
The vitamin D from spinach also has vitamin C in the form of a cofactor, called VAF2.
It is this vitamin C that is converted into vitamin D,” said SchramM.
Soh added that the results of the research are important to people who consume vitamin-rich vegetables and fruits.
“There are several reasons to eat vitamin- and mineral-rich plant foods.
Many of them have high levels.
For example, a small amount of spinach can have a substantial amount of calcium, vitamin A and C,” said Soh.
“Another important reason is that they contain the coenulins vitamin B-12 and vitamin C as well as other coenolases that enhance vitamin D absorption,” Sohn added.
“But, as we learn more about the biology of vitamin synthesis and production, we will be able to make better food choices that are more likely to meet our needs.”