Favorite Link Friday

Abraham Lincoln and the Mother of Thanksgiving

On October 3, 1863, with the nation embroiled in a bloody Civil War, President Abraham Lincoln issued a proclamation setting aside the last Thursday in November as a national day of thanks, setting the precedent for the modern holiday we celebrate today.

Secretary of State William Seward wrote it and Abraham Lincoln issued it, but much of the credit for the proclamation should probably go to a woman named Sarah Josepha Hale. A prominent writer and editor, Hale had written the children’s poem “Mary Had a Little Lamb,” originally known as “Mary’s Lamb,” in 1830 and helped found the American Ladies Magazine, which she used a platform to promote women’s issues. In 1837, she was offered the editorship of “Godey’s Lady Book,” where she would remain for more than 40 years, shepherding the magazine to a circulation of more than 150,000 by the eve of the Civil War and turning it into one of the most influential periodicals in the country. In addition to her publishing work, Hale was a committed advocate for women’s education (including the creation of Vassar College in Poughkeepsie, New York), and raised funds to construct Massachusetts’s Bunker Hill Monument and save George Washington’s Mount Vernon estate.

The New Hampshire-born Hale had grown up regularly celebrating an annual Thanksgiving holiday, and in 1827 published a novel, “Northwood: A Tale of New England,” that included an entire chapter about the fall tradition, already popular in parts of the nation. While at “Godey’s,” Hale often wrote editorials and articles about the holiday and she lobbied state and federal officials to pass legislation creating a fixed, national day of thanks on the last Thursday of November—a unifying measure, she believed that could help ease growing tensions and divisions between the northern and southern parts of the country. Her efforts paid off: By 1854, more than 30 states and U.S. territories had a Thanksgiving celebration on the books, but Hale’s vision of a national holiday remained unfulfilled. Read the rest here.

Vitamin D is Actually a Hormone

The weight of the literature suggests that vitamin D is indeed a hormone, not a nutrient, said Michael Holick, MD, PhD, of Boston University.

"By definition, vitamin D is a hormone," Holick told MedPage Today. "The body synthesizes it after sun exposure, and it's activated by the liver and kidneys. That activated form again acts like a hormone to regulate calcium metabolism." No other vitamin goes through the process of activation that D does before it can be used by the body, Holick said. First, the skin must synthesize vitamin D3, or cholecalciferol, after exposure to UVB radiation. D3 is then metabolized by the liver into 25-hydroxyvitamin D, or 25(OH)D, and then moves on to the kidney where it is converted to the biologically active form 1,25-dihydroxyvitamin D, or 1,25(OH)2D. Read the rest Here

Benefits of "Vitamin" D

Evidence of vitamin D's protective effect against cancer is compelling. For more than 50 years, documentation in the medical literature suggests regular sun exposure is associated with substantial decreases in death rates from certain cancers and a decrease in overall cancer death rates. Recent research suggests this is a causal relationship that acts through the body's vitamin D metabolic pathways. For instance, some evidence points to a prostate, breast and colon cancer belt in the United States, which lies in northern latitudes under more cloud cover than other regions during the year. Rates for these cancers are two to three times higher than in sunnier areas.

Other studies bear out vitamin D's importance to bone health, to the point where it's now widely known that vitamin D deficiency is associated with hip fractures, and that supplementation helps. Unfortunately, not everyone is getting enough vitamin D. A recent study showed that 37 percent of adult hospital patients were deficient in vitamin D upon admission. Two-thirds of these patients did not consume enough vitamin D from dietary sources. Surprisingly, 46 percent of those who took daily multivitamins (most of which provide 400 IU) were also in a state of deficiency. Experts now suggest people take 600 IU vitamin D daily, and up to 800 IU a day for elderly patients, because as people age they do not produce vitamin D from sun exposure as easily as they did when younger. Read the rest here.

The Secret Ingredient in Your Orange Juice

Haven’t you ever wondered why every glass of Tropicana Pure Premium orange juice tastes the same, no matter where in the world you buy it or what time of year you’re drinking it in? Or maybe your brand of choice is Minute Maid or Simply Orange or Florida’s Natural. Either way, I can ask the same question. Why is the taste and flavor so consistent? Why is it that the Minute Maid never tastes like the Tropicana, but always tastes like its own unique beverage?

The reason your store bought orange juice is so consistently flavorful has more to do with chemistry than nature. Making OJ should be pretty simple. Pick oranges. Squeeze them. Put the juice in a carton and voilà! But actually, there is an important stage in between that is an open secret in the OJ industry.

After the oranges are squeezed, the juice is stored in giant holding tanks and, critically, the oxygen is removed from them. That essentially allows the liquid to keep (for up to a year) without spoiling– but that liquid that we think of as orange juice tastes nothing like the Tropicana OJ that comes out of the carton. Read the rest here.

Pi (No, Not that Pie) is Even More Involved With Science Than Previously Thought

Researchers from the University of Rochester discovered that a formula which approximates the energy levels of a hydrogen atom is the same as the one developed 360 years ago by English mathematician John Wallis to find the value of Pi.

The pair of physicists realized that when the variational method was employed to calculate the energy levels of the hydrogen atoms, the formula could be simplified into the Wallis Product, the one used for Pi.

The variational method is used to approximate the lower energy states of atoms, when the electrons are close to the nucleus. It is not usually used on the hydrogen atom, as hydrogen is simple enough so scientists can compute the energy levels precisely. Energy levels give an indication of how tightly bound the electron is to an atom; the larger the energy level, the easier it is for the electron to break free. Read the rest here.

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