Check your risk factors for Vitamin D deficiency.
Vitamin D has been increasingly recognized by the medical community for its anti aging benefits. This hormone (it is not really a vitamin) is important for healthy bones and muscles, improves functioning of the immune system and is necessary for cardiac health. We get most of our vitamin D from the sun, either from the interaction of our skin with sunlight or through plants whose skin has interacted with the sun’s rays.
Given the abundance of sunlight, it is surprising to note that one in three Americans has vitamin D deficiency. However, according to 2011 National Center for Health Data statistics, almost one in three Americans has vitamin D blood levels the threshold that the Institute of Medicine (IOM) says is needed for good bone health.
In its Healthbeat newsletter, experts at Harvard Medical School reviewed a report in the Swedish Medical Journal Acta Dermato-Venerologica that discussed nine factors that can influence vitamin D levels. They are:
1. The latitude where you live. At higher latitudes, the amount of vitamin D–producing UVB light reaching the earth’s surface goes down in the winter because of the low angle of the sun.
2. The air pollution where you live. Carbon particulates in the air from the burning of fossil fuels, wood, and other materials scatter and absorb UVB rays. Ozone absorbs UVB radiation, so holes in the ozone layer could be a pollution problem that winds up enhancing vitamin D levels.
3. Your use of sunscreen — in theory. Sunscreen prevents sunburn by blocking UVB light, so theoretically, sunscreen use lowers vitamin D levels. But as a practical matter, very few people put on enough sunscreen to block all UVB light, or they use sunscreen irregularly, so sunscreen’s effects on our vitamin D levels might not be that important.
4. The color of your skin. Melanin is the substance in skin that makes it dark. It “competes” for UVB with the substance in the skin that kick-starts the body’s vitamin D production. As a result, dark-skinned people tend to require more UVB exposure than light-skinned people to generate the same amount of vitamin D.
5. The temperature of your skin. Warm skin is a more efficient producer of vitamin D than cool skin. So, on a sunny, hot summer day, you’ll make more vitamin D than on a cool one.
6. Your weight. Fat tissue sops up vitamin D, so it’s been proposed that it might be a vitamin D rainy-day fund: a source of the vitamin when intake is low or production is reduced. But studies have also shown that being obese is correlated with low vitamin D levels and that being overweight may affect the bioavailability of vitamin D.
7. Your age. Compared with younger people, older people have lower levels of the substance in the skin that UVB light converts into the vitamin D precursor, and there’s experimental evidence that older people are less efficient vitamin D producers than younger people.
8. The health of your gut. The vitamin D that is consumed in food or as a supplement is absorbed in the part of the small intestine immediately downstream from the stomach. Stomach juices, pancreatic secretions, bile from the liver, the integrity of the wall of the intestine — they all have some influence on how much of the vitamin is absorbed. Therefore, conditions that affect the gut and digestion, like celiac disease, chronic pancreatitis, Crohn’s disease, and cystic fibrosis, can reduce vitamin D absorption.
9. The health of your liver and kidneys. Some types of liver disease can reduce absorption of vitamin D because the ailing liver isn’t producing normal amounts of bile. With other types, steps essential to vitamin D metabolism can’t occur — or occur incompletely. Levels of the bioactive form of vitamin D tend to track with the health of the kidneys, so in someone with kidney disease, bioactive vitamin D levels decrease as the disease gets worse, and in end-stage kidney disease, the level is undetectable.
Symptoms of vitamin D deficiency include muscle and bone weakness, respiratory problems (especially in children) and cognitive impairment in older adults. The most accurate way to measure how much vitamin D is in your body is the 25-hydroxy vitamin D test.
Vitamin D has been increasingly recognized by the medical community for its anti aging benefits. This hormone (it is not really a vitamin) is important for healthy bones and muscles, improves functioning of the immune system and is necessary for cardiac health. We get most of our vitamin D from the sun, either from the interaction of our skin with sunlight or through plants whose skin has interacted with the sun’s rays.
Given the abundance of sunlight, it is surprising to note that one in three Americans has vitamin D deficiency. However, according to 2011 National Center for Health Data statistics, almost one in three Americans has vitamin D blood levels the threshold that the Institute of Medicine (IOM) says is needed for good bone health.
In its Healthbeat newsletter, experts at Harvard Medical School reviewed a report in the Swedish Medical Journal Acta Dermato-Venerologica that discussed nine factors that can influence vitamin D levels. They are:
1. The latitude where you live. At higher latitudes, the amount of vitamin D–producing UVB light reaching the earth’s surface goes down in the winter because of the low angle of the sun.
2. The air pollution where you live. Carbon particulates in the air from the burning of fossil fuels, wood, and other materials scatter and absorb UVB rays. Ozone absorbs UVB radiation, so holes in the ozone layer could be a pollution problem that winds up enhancing vitamin D levels.
3. Your use of sunscreen — in theory. Sunscreen prevents sunburn by blocking UVB light, so theoretically, sunscreen use lowers vitamin D levels. But as a practical matter, very few people put on enough sunscreen to block all UVB light, or they use sunscreen irregularly, so sunscreen’s effects on our vitamin D levels might not be that important.
4. The color of your skin. Melanin is the substance in skin that makes it dark. It “competes” for UVB with the substance in the skin that kick-starts the body’s vitamin D production. As a result, dark-skinned people tend to require more UVB exposure than light-skinned people to generate the same amount of vitamin D.
5. The temperature of your skin. Warm skin is a more efficient producer of vitamin D than cool skin. So, on a sunny, hot summer day, you’ll make more vitamin D than on a cool one.
6. Your weight. Fat tissue sops up vitamin D, so it’s been proposed that it might be a vitamin D rainy-day fund: a source of the vitamin when intake is low or production is reduced. But studies have also shown that being obese is correlated with low vitamin D levels and that being overweight may affect the bioavailability of vitamin D.
7. Your age. Compared with younger people, older people have lower levels of the substance in the skin that UVB light converts into the vitamin D precursor, and there’s experimental evidence that older people are less efficient vitamin D producers than younger people.
8. The health of your gut. The vitamin D that is consumed in food or as a supplement is absorbed in the part of the small intestine immediately downstream from the stomach. Stomach juices, pancreatic secretions, bile from the liver, the integrity of the wall of the intestine — they all have some influence on how much of the vitamin is absorbed. Therefore, conditions that affect the gut and digestion, like celiac disease, chronic pancreatitis, Crohn’s disease, and cystic fibrosis, can reduce vitamin D absorption.
9. The health of your liver and kidneys. Some types of liver disease can reduce absorption of vitamin D because the ailing liver isn’t producing normal amounts of bile. With other types, steps essential to vitamin D metabolism can’t occur — or occur incompletely. Levels of the bioactive form of vitamin D tend to track with the health of the kidneys, so in someone with kidney disease, bioactive vitamin D levels decrease as the disease gets worse, and in end-stage kidney disease, the level is undetectable.
Symptoms of vitamin D deficiency include muscle and bone weakness, respiratory problems (especially in children) and cognitive impairment in older adults. The most accurate way to measure how much vitamin D is in your body is the 25-hydroxy vitamin D test.
