By TIFFANY RONEY
Slather on the sunscreen. Stay in the shade. Protect from the sun at all costs. This type of advice has reigned in skincare for years, but a researcher from Abilene said the sun is actually an excellent source of a vitamin everyone needs.
However, the sun is not the only source. Read on for how to acquire healthy levels of this vitamin and, thus, how to grow strong bones and lessen the risk of disease.
A three-letter question: “Why?”
Steve Henry, one of the top swine veterinarians in the world, and his coworkers Megan Potter and Lisa Tokach, veterinarians at Abilene Animal Hospital, examined bones of baby pigs and found them weaker than they ought to be. Though the pigs had been on the “perfect diet” of their mother’s milk, as Potter said, they were low in calcium and their bones broke easily. Potter asked why.
Lisa Tokach, also a veterinarian at Abilene Animal Hospital, said Potter asks the “why” question often.
“I think you always need to know why,” Potter said. “Absolutely.”
Henry said he did not know why the pigs had weak bones so Potter replied, “Well, let’s go find out.”
This conversation led Henry, Potter and Tokach on a journey of seeking answers. This journey led them to Ron Horst and Jesse Goff, a pair of vitamin D experts in Ames, Iowa.
“If you come up to Ames,” Goff said, “we’ll explain to you what’s going on.”
In their research at Ames, the Abilene veterinarians learned low levels of vitamin D made bones unable to calcify normally. Calcification is the accumulation of calcium salts, which is the process that gives bones strength. To solidify their research, the veterinarians checked vitamin D levels in the blood of pigs in Arizona, Illinois, Oklahoma and Iowa. No matter where they looked, they found unexpectedly low levels of vitamin D.
Get in the sun
People and most mammals receive vitamin D in two ways: from the sun and from their diets. In both of these ways of receiving though, there are stipulations.
“Now the interesting part is that once the sun’s angle to the earth drops below 35 degrees, ultra-violet beta light wavelengths can’t get in and we go into what’s known as ‘vitamin D winter,’ so we don’t make any vitamin D all winter long, even outside in the sunshine,” Henry said.
Thus, a person or animal could stand outside all day in the winter and not produce any vitamin D. When D-producing ultraviolet rays are unavailable, people can ingest vitamin D by taking supplements, drinking fortified milk and eating fatty fish. For pigs, though, there are no natural dietary sources.
The veterinarians asked Horst and Goff why sows did not provide vitamin D to their babies. They presumed sows do not expend their resources transmitting D to their babies because their bodies assume the babies will receive vitamin D from the sun. Today, almost all baby pigs are kept indoors for warmth and protection so they do not receive sunlight. Furthermore, many pigs are raised at latitudes that do not receive year-round D-producing rays.
To try another way to give baby pigs the vitamin D they needed, the veterinarians – under the guidance of the Ames experts – decided to give an oral dose of vitamin D to pigs that were 2-3 days old.
“We’d give these little baby pigs a squirt of vitamin D in their mouths,” Henry said.
They also kept a control group of pigs that received no vitamin D. At the end of the experiment, the control group’s vitamin D levels remained low. The ones treated with vitamin D, though, tested differently.
“We got them pretty close to normal,” Henry said. “So, what Ron and Jesse thought would work, worked.”
With just a single oral dose, the veterinarians raised the baby pigs’ vitamin D levels to a normal standard, and the results lasted for three weeks.
“We got them close to where they should be, and we’re pretty happy with it,” Henry said. “Now, we do that with almost all the babies.”
What about pigs in the sunshine?
This solution led to another question for the Abilene veterinarians who, by this point, had been on the vitamin D trail for several months.
“All this time, people kept asking the question about, ‘What kind of vitamin D levels do babies that are born outdoors have?’” Henry said.
At the Central Kansas Free Fair in August 2010, Henry shared his question with a family from Tampa, Kan., who had two litters of month-old pigs that were born outdoors. The family invited Henry and his coworkers to visit their farm and take blood samples of the pigs.
“So I went down, along with Kyle, who’s 8th grade, I suppose and his little sister, and a half-grown puppy and the mud and the boots and we chased these pigs down and got their blood samples,” Henry said. “We called them ‘sunshine pigs.’”
After analyzing the blood samples in Ames, Henry found the pigs had vitamin D levels three times higher than levels of pigs that lived indoors. Thus, sunshine pigs produced enough vitamin D to grow strong bones.
From pigs to people
While low levels of vitamin D in pigs mainly lead to bone strength problems, low levels of vitamin D in people can raise the risk for a splintering of problems like multiple sclerosis, type 1 diabetes and various kinds of cancer. Thus, it was important to the veterinarians to look not only at the needs of pigs but also those of people.
“Think about the people, the population you know that have fragile bones, and how much sunlight they get,” Henry said. “Who would you be thinking?”
The answer Henry sought: older people.
Despite their general lack of sun exposure as a population, Henry said older people can still have healthy levels if they take vitamin D supplements.
Like “sunshine pigs,” people who receive high levels of sunshine have higher levels of vitamin D than those who stay inside.
“Lifeguards in Missouri and highway construction workers and the Masai people in Africa that don’t wear many clothes but are out there running around – turns out they have these (higher) levels,” Henry said, pointing to a graph.
Not everyone, though, is able to spend enough time outside or lives in a location where they can receive vitamin D year-round.
“Too much sun, you’ve got to worry about. ‘Am I going to create skin cancer problems?’” Henry said. “In the early 80s, it seemed like all the U.S. vitamin D levels slid down a notch. So, what happened in the early 80s that might have resulted in all the vitamin D levels sliding down?”
Henry said it was in the 1980s that people took up the concern of putting sunscreen on their children before letting them play outdoors.
“Fix one problem, cause two more,” Tokach said.
Potter suggested people get their vitamin D levels tested by a physician and inquire how to raise them. As stated earlier in this article, Henry cited supplements, fortified milk and fatty fish as sources of vitamin D. Fatty fish include salmon, tuna, trout, herring and sardines, according to webmd.com.
Responding to the research
Due to the Abilene Animal Hospital vet-erinarians’ research, it is becoming more popular throughout the swine industry for pig owners to give vitamin D to their pigs. Additionally, the veterinarians’ research spurred research by K-State students in the animal science department. Their work is published at www.ksuswine.org. Beyond pigs, the human medical field is continuing to learn more about the effects of vitamin D on health and immunity.
Henry said vitamin D is cheap to make. One popular source is lanolin from sheep wool. Manufacturers, mostly in China, shear sheep, extract lanolin from the wool, radiate it with UV beta rays and make vitamin D. The vitamin D is then packaged into vitamin tablets.
“The bright, intelligent people around us make us connect the dots, and there’s just a lot of dots out there,” Henry said. “It isn’t like you can sit in class and get it all, because it’s happening faster than we can soak it up. So, out of this little Kansas town of Abilene, poking around with baby pigs has changed health for a lot of pigs around the country. And it’s kind of taught us a lot about ourselves and people in general.”