Winter is prime time for warm soup and hot chocolate by the fireplace.
JoEllen Welsh says people in the Northeast should make time for another seasonal tradition — vitamin D — during the cold weather season.
Welsh, a professor at the University at Albany’s Gen*NY*Sis Center for Excellence in Cancer Genomics who has researched the role of vitamin D in breast cancer, said the vitamin is vital for bone strength and cellular health. Now is the time to make sure levels are correct, she said, because people lose natural supplies of vitamin D during late autumn.
“Vitamin D is synthesized in the skin when we go outside in the sun,” Welsh said. “There is a chemical within our skin that is activated and converted to vitamin D. This is the same as the vitamin D that we get in our diet or in our supplemented foods or pills.”
People who live in a sunny climate or spend plenty of time in the sun, Welsh said, do not have to rely on dietary sources of the fat-soluble vitamin D.
“But up here in the north, obviously we have cloud cover, we have winter and we don’t make any vitamin D from about November to April,” Welsh said. “So we’re really, really pushing people to be aware that they have to eat or consume foods that contain vitamin D or they have to take a supplement during the winter, at least.”
The sun’s position during winter months means people in the Northeast receive weaker, less potent sunlight. Even if winter sunlight were stronger, Welsh said, most skin is covered by winter hats, coats and pants.
Vitamin D deficiency is a serious health concern, according to Dr. Michael Holick. He wrote about deficiency in his 2010 book “The Vitamin D Solution: A 3-Step Strategy to Cure our Most Common Health Problems.”
“People cannot feel vitamin D deficiency and that’s why people haven’t really taken vitamin D deficiency very seriously,” Holick said in an interview with his publisher, Hudson Street Press. “But we’re now recognizing that vitamin D deficiency has very serious health consequences — increasing your risk of common cancers, Type 1 diabetes, Type 2 diabetes, auto-immune diseases like multiple sclerosis and rheumatoid arthritis, increasing risk of heart disease, increasing risk of heart attack and stroke, increasing risk of having depression.”
Holick said symptoms of vitamin D deficiency are often aches and pains in muscles and bones.
“Often physicians mis-diagnose this as fibromyalgia, chronic fatigue syndrome or simply will write the patient off as being depressed,” Holick said, “not realizing these are classic signs and symptoms for vitamin D deficiency.”
People have been told that vitamin C helps fight winter colds. Welsh said vitamin D is important for strong bones.
“It’s needed to maintain the amount of calcium in the system and calcium is what hardens bone,” Welsh said. “If you don’t have vitamin D, then you’re not going to absorb calcium from your diet and then your bone density will suffer.”
Without vitamin D, bones will become rubbery. In children, Welsh said, vitamin D deficiency can cause weight support issues — and kids may become bowlegged. In adults, osteomalacia can develop — soft bones.
The vitamin does more than help with proper calcium levels. Welsh said researchers have learned vitamin D reacts with a “receptor” found in body cells.
“With respect to cancer, we think it’s important for vitamin D to be present to activate this receptor in the normal cells and prevent them from progressing into cancer cells,” she said. “It’s like a key into a lock. Vitamin D would be the key going into the cell and turning on this mechanism to protect the cells from cancer development. We’ve also seen the effects of Vitamin D on the cardiovascular system and diabetes and the immune system. So it’s in all cells, this receptor. And in different cells it does different things.”
Welsh said about 20 percent of the U.S. population is living with vitamin D deficiency. Because blacks and Hispanics have darker skin and are unable to produce vitamin D naturally, Welsh said, the deficiency figure is between 40 and 50 percent.
“It’s a substantial number we’re talking about,” she said.
Newborns who are being breast fed by their mothers can also be at risk.
“There’s not a lot of vitamin D in breast milk, so babies that are exclusively breast fed may be at risk,” Welsh said. “In fact, there’s been a resurgence of rickets in breast-fed babies. A lot of women think that breast milk is the perfect food and obviously think no other supplements are needed. But vitamin D is an exception.”
People can get their winter doses of “D” relatively easy. Vitamin pills are one way, as long as people are getting a minimum of 600 international units (IU) of vitamin D every day.
The 600 units value is relatively new. Welsh said multi-vitamins used to contain 400 units of vitamin D; the new number is meant to just maintain their current vitamin D levels.
“For some people who are deficient, they can get prescriptions for vitamin D up to 50,000 units in a pill they would take once a week,” Welsh said. “I guess the bottom line is if people are concerned that they don’t get out in the sun enough or don’t have a supplement or don’t eat foods that are high in vitamin D, then they should get the vitamin D blood test, which will determine where they are. Are they deficient, are they just a little bit low or are they fine? From there, we can determine what is needed.”
The U.S. Drug and Food Administration, on its website, said there are health risks in taking too much of some supplements, such as vitamins A, D and iron. And the agency also cautions about unsafe amounts of liquid vitamin D given to infants. The FDA recommends that a dropper used to give infants vitamin D not hold more than 400 units — to reduce the possibility of dosing errors.
People can also find vitamin D in food sources. But that can be difficult.
“The problem is it’s not hardly in any foods,” Welsh said. “It’s in fatty fish, not all fish, fatty fish like salmon is a good source. It’s in egg yolks, and basically not much else.”
Fish oil capsules — in the news earlier this year as a study published in the Journal of the American Medical Association found that the capsules may not be as beneficial to cardiac health as once thought — may not be vitamin D boosters.
“Most of the fish oils are designed to provide the omega fatty acids and not provide vitamin D,” Welsh said. “So the actual cod liver oil that they used to give kids in the ’20s is what does contain huge amounts of vitamin D and also vitamin A.”
Cod liver oil may not be the answer for 2012.
“One of the issues that we still don’t know,” Welsh said, “we don’t know what is the relative amount of vitamin D versus vitamin A that we need because in some cases they’re competitive with each other … we haven’t really sorted that out in the lab. For most people I would recommend going with just a pure vitamin D tablet. A lot of them also have calcium, which isn’t necessarily bad, but you don’t really need extra calcium if you have the vitamin D.”
Some foods advertise that vitamin D has been added. Milk is one of these products, so is orange juice.
“You have to read the labels,” Welsh said. “Some of these supplemented foods do have vitamin D added but it’s not at very high amounts.”
Once the sun is in a more favorable position to provide the Northeast with strong rays of light, vitamin D fans will get their fair shares. But they will also have to worry about sun damage.
“One of the things that we suggest in mid-summer, when you do have the risk of burning, just expose the skin for maybe 10, 15 minutes and then apply the sunscreen,” Welsh said. “That’s the sensible way, but that’s easy to forget or people don’t pay attention to the adding the sunscreen part. You have to use your good judgment. Some people tan better than others, some people burn and so it’s really a matter of knowing your own skin type, knowing your environment and knowing your vitamin D status.
People don’t have to take a 15-minute sun shower every day. “Probably every couple days would be sufficient,” Welsh said.