- What are the health benefits of vitamin D?
- 4 Ways to Make Sure You’re Getting Enough Vitamin D
- How to Increase Vitamin D Levels Quickly
- What is Vitamin D?
- The Health Benefits of Vitamin D
- The Dangers of Vitamin D Deficiency
- Getting Vitamin D the Natural Way
- The Benefits of Vitamin D Supplements
- How Much is Too Much?
- Don’t Let a Vitamin D Deficiency Keep You Down
- What Is Vitamin D?
- How Much Vitamin D Does Your Body Need?
- Symptoms of Vitamin D Deficiency
- Causes of Vitamin D Deficiency & Who Is At Risk
- Remedies for Vitamin D Deficiency
- Can You Take Too Much Vitamin D?
- What Nutrients Complement Vitamin D?
- Points to Remember
- Managing Rheumatoid Arthritis: 5 Easy Ways to Boost Vitamin D Intake
- How to Get More Vitamin D
- Vitamin D and your health: Breaking old rules, raising new hopes
- Breaking the old rules
- What is vitamin D?
- How it works
- Vitamin D deficiencies
- Osteoporosis and fractures
- Prostate cancer
- Other malignancies
- “D” right amount
- Delivering D
- New light on the sunshine vitamin
What are the health benefits of vitamin D?
Share on PinterestDuring sun exposure, a person’s body produces vitamin D.
Vitamin D has multiple roles in the body. It assists in:
- promoting healthy bones and teeth
- supporting immune, brain, and nervous system health
- regulating insulin levels and supporting diabetes management
- supporting lung function and cardiovascular health
- influencing the expression of genes involved in cancer development
Read on to find out about these roles in more detail:
1. Healthy bones
Vitamin D plays a significant role in the regulation of calcium and maintenance of phosphorus levels in the blood. These factors are vital for maintaining healthy bones.
People need vitamin D to allow the intestines to stimulate and absorb calcium and reclaim calcium that the kidneys would otherwise excrete.
Vitamin D deficiency in children can cause rickets, which leads to a severely bowlegged appearance due to the softening of the bones.
Similarly, in adults, vitamin D deficiency manifests as osteomalacia, or softening of the bones. Osteomalacia results in poor bone density and muscular weakness.
A vitamin D deficiency can also present as osteoporosis, for which over 53 million people in the United States either seek treatment or face an increased risk.
2. Reduced risk of flu
A 2018 review of existing research suggested that some studies had found that vitamin D had a protective effect against the influenza virus.
However, the authors also looked at other studies where vitamin D did not have this effect on flu and flu risk.
Further research is, therefore, necessary to confirm the protective effect of vitamin D on the flu.
3. Healthy infants
Vitamin D deficiency has links to high blood pressure in children. One 2018 study found a possible connection between low vitamin D levels and stiffness in the arterial walls of children.
The American Academy of Allergy Asthma and Immunology (AAAAI) suggest that evidence points to a connection between low vitamin D exposure and an increased risk of allergic sensitization.
An example of this is children who live closer to the equator and have lower rates of admission to hospital for allergies plus fewer prescriptions of epinephrine autoinjectors. They are also less likely to have a peanut allergy.
The AAAAI also highlight an Australian study of egg intake. Eggs are a common early source of vitamin D. The children who started eating eggs after 6 months were more likely to develop food allergies than children who started between 4–6 months of age.
Furthermore, vitamin D may enhance the anti-inflammatory effects of glucocorticoids. This benefit makes it potentially useful as a supportive therapy for people with steroid resistant asthma.
4. Healthy pregnancy
A 2019 review suggests that pregnant women who are deficient in vitamin D may have a greater risk of developing preeclampsia and giving birth preterm.
Doctors also associate poor vitamin D status with gestational diabetes and bacterial vaginosis in pregnant women.
It is also important to note that in a 2013 study, researchers associated high vitamin D levels during pregnancy with an increased risk of food allergy in the child during the first 2 years of life.
4 Ways to Make Sure You’re Getting Enough Vitamin D
It can be hard to make sure you’re getting the right amount of important nutrients every day, but one that people tend to overlook is vitamin D.
You can get vitamin D naturally from the sun, so chances are you’re getting enough, right? That’s not actually true. In fact, 75 percent of Americans have a vitamin D deficiency—a condition that can lead to weak bones, a poor immune system and a higher risk for cardiovascular disease, diabetes and more.
So how much do you need? The daily recommended dose of vitamin D for adults under the age of 70 is 600 international units (IU—the way vitamin D is measured). For adults over the age of 70, the daily dose is 800 IU. Not sure what that means? Here are simple things you can do to make sure you’re getting enough every day:
- Get more sun. A quick 10-minute walk during the middle of the day in the summertime can give your body all of the vitamin D you need for the day. The key is wearing shorts and a tank top (if you’re going out for longer, definitely slather on the SPF to protect yourself). Your body even stores some of the extra vitamin D to help you during the darker winter months (Michigan doesn’t get enough sunlight in the winter to give your body enough vitamin D). If you have darker skin, you might need to spend up to an hour in the sun to get the same amount of vitamin D.
- Eat foods that are rich in vitamin D. Beef, chicken and fatty fish are all rich in vitamin D. If you like seafood, try incorporating more salmon, shrimp, mackerel, sardines and fresh herring into your diet. Even vegetables like spinach, kale and okra are rich in vitamin D. Vitamin D is also added to some foods like tofu, orange juice and a few dairy products.
- Eat breakfast. Just two eggs, a glass of orange juice and a bowl of cereal and milk can add up to about 300 IU of vitamin D—half of what you need for the day.
- Talk to your primary doctor about supplements. If you are not able to get much sun, it’s the winter or your diet is low in vitamin D, a supplement may be a good idea. Look for a supplement that says it’s vitamin D3—that’s the kind of vitamin D that’s produced naturally by your skin and is the easiest for your body to absorb.
Your doctor might suggest a vitamin D test, which can determine if you have a deficiency or not. You only need one if you have other risk factors, like osteoporosis. And while low vitamin D levels are bad, so are high levels. Too much vitamin D—more than 4,000 IU a day—can be damaging to your kidneys.
Like this post? Check these out:
- 6 Surprising Ways to Beat Vitamin D Deficiency
- 4 Easy Ways to Get More Vitamin C
- The Vitamins and Minerals You Need as You Age
Photo credit: margouillatphotos
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Vitamin D is an essential component of health. This hailed vitamin is most famously responsible for bone health, but some data suggests this vitamin may also play a role in protecting you from diseases such as diabetes, heart disease, certain types of cancer and even depression.
And vitamin D deficiency is no joke. It can cause osteoporosis, osteomalacia, brittle bones and increase your risk of fractures. A lack of vitamin D can even affect your immune and nervous system.
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Luckily, sunlight (in moderation), supplements and food sources can help get your numbers up to where they should be.
“Many people are able to meet their daily requirement of vitamin D from sun exposure and a balanced diet,” says registered dietitian Anna Taylor, MS, RD, LD, CDE. “But certain groups of people are more likely to develop a deficiency.”
Those most at risk for vitamin D deficiency include:
- Older adults.
- People with limited sun exposure.
- People who are obese or who have had gastric bypass surgery.
- Those with dark skin.
- Infants who are exclusively breastfed without vitamin D supplementation.
- People with certain digestive diseases that result in malabsorption.
For most children and adults, about 600 international units per day is recommended, however it can range up to 4,000 international units per day depending on health needs. (Most supplements offer about 2,000 international units of vitamin D per pill.)
Vitamin D: Whole foods vs. fortified foods
Fortified foods are meant to help boost vitamin and mineral intake. They’re designed to add nutrients that don’t naturally occur in the product. Sometimes iron, fiber, zinc or vitamin A is added. For instance, most milk is fortified with vitamin D and calcium is sometimes added to orange juice.
“Since so few foods found in nature are good sources of vitamin D, fortified foods provide most of the vitamin D found in the American diet,” explains Taylor.
But she warns that some fortified foods can contain added ingredients that make the product less healthy, like sugar or hydrogenated fats. Cow’s milk and most plant alternative milks are typically fortified with vitamin D, but it’s important to look for products with no added sugar.
Many types of yogurt and cereal are also fortified with vitamin D, but could contain excessive added sugar or saturated fat. Margarine is often fortified as well, but some products contain partially hydrogenated oils, which should be avoided. Read labels to choose the best product for your family.
Vitamin D foods
One of the best ways to get enough vitamin D in your diet is to eat a variety of healthy foods from all of the food groups, including some fortified foods. Also aim for about 15 minutes of mid-day sun exposure at least twice per week.
Foods that provide vitamin D include:
International units per serving.
How to Increase Vitamin D Levels Quickly
It’s not always easy to tell if you’re getting enough vitamin D. The early indicators of a vitamin D deficiency ? fatigue, hypertension, and depression ? can all be explained as the results of stress or other factors. The only way to know for sure if you have a deficiency is to get tested, which most people rarely do. Unless you regularly spend time in direct sunlight, there’s a good chance you are lacking the vitamin D your body needs to operate at its best.
Maintaining healthy levels of vitamin D is crucial for many of your body’s functions, but many of us aren’t getting nearly enough of it. Recent studies have shown that nearly nine out of ten adults in the United States are vitamin D deficient, which is linked to increased risks of various cancers, cardiovascular disease, immune disorders, depression, and other adverse health conditions.
If you’re suffering from a vitamin D deficiency, it’s in your best interest to get yourself back up to recommended amounts quickly. Restoring your levels to where they should be can help prevent health problems and leave you feeling and functioning better in your daily life. Fortunately, there are many simple, healthy, and effective ways to increase vitamin D levels.
What is Vitamin D?
Vitamin D is a vitamin that our bodies can produce naturally. It’s stored in the liver, but because vitamin D is fat-soluble, it can also be absorbed by fatty tissues, which prevent it from being put to good use elsewhere in the body. Being overweight can make it harder for your body to circulate the vitamin D it needs.
Vitamin D works as a secosteroid hormone in our bodies, and the human body creates it by absorbing sunlight. Ultraviolet rays convert a type of cholesterol in our skin into vitamin D3. Vitamin D2, the other type of vitamin D, typically comes to us from the foods we eat.
Sunshine is one of the best natural sources of vitamin D.
Once the vitamin passes into our bloodstream and goes through our liver and kidneys, it goes through enzymatic conversion, converting it into metabolites that function like hormones. These metabolites are what vitamin D tests measure to determine whether or not you have a deficiency.
After they’ve been activated, the vitamin D metabolites then go to work helping our bodies absorb necessary minerals. They also help to regulate mood and blood pressure, maintain our immune system and bone structure, and carry out many other vital functions.
The Health Benefits of Vitamin D
Some of the benefits associated with keeping up your vitamin D levels include:
- Maintaining healthy bones and teeth
- Supporting the immune system
- Reducing feelings of depression and anxiety
- Preventing certain types of cancer
- Reducing the risk of developing Type 2 Diabetes
- Improving muscle strength and function
Strengthening our bones is one of the primary and most important functions of vitamin D, as it makes it easier for us to absorb calcium and phosphorus through our intestines. This benefit is particularly important for older people, as the increased bone and muscle strength can help prevent falls, which are a major cause of serious injury for the elderly.
Vitamin D has also been shown to help our bodies defend against respiratory infection, like influenza and the common cold.
The Dangers of Vitamin D Deficiency
On the other side of the coin, having low levels of vitamin D can result in an increased risk of harmful conditions, such as:
- A weakened immune system
- Dementia and Alzheimer’s disease
- High blood pressure
There are a number of other diseases and conditions that are associated with a lack of vitamin D, such as hair loss, muscle pain, inflammatory bowel disease, and fibromyalgia.
Vitamin D is also important for pregnant women, as low levels of vitamin D during pregnancy have been linked to increased rates of preeclampsia, gestational diabetes, and low birth weight.
Getting Vitamin D the Natural Way
It’s usually not difficult to naturally increase vitamin D levels, primarily through exposure to sunlight and by eating foods rich in vitamin D. Sunlight is actually the most efficient way to get your daily recommended dose of vitamin D, as your skin is quite effective at producing it naturally when exposed to ultraviolet light from the sun.
For most adults, ten to twenty minutes in direct sunlight is enough to absorb enough vitamin D for the day. Lighter-skinned people absorb vitamin D more quickly than people with darker skin, so if you fall into the latter category, you may need to spend more time ? up to forty minutes ? to get the amount of vitamin D you need.
While it’s always a good idea to protect yourself against the possibility of developing skin cancer, it is true that sunscreen prevents vitamin D absorption. If you can, spend some time in the sun getting your daily dose of vitamin D before you put sunscreen on, or just apply sunscreen to the more sensitive parts of your body, like your face.
Vitamin D helps build strong bones.
But certain medications, like antibiotics or even Ibuprofen, can make people more susceptible to exposure from the Sun. Standing in the sun for even a few minutes could mean a sun rash or worse. Similarly, certain people just burn more easily in the sun, due to the makeup of their genes. All of this makes supplements, like a vitamin D spray, a safer choice. It’s also a metered dose, making it easier to know exactly how much you’re getting. (And it tastes great!)
Diet can also be an important source of vitamin D. Some foods that are naturally rich in vitamin D include:
In addition to these sources, some foods are fortified with vitamin D, like milk, yogurt, cereal, and orange juice. Certain mushrooms can also be a good source of vitamin D if they have been exposed to ultraviolet light while growing.
In order to actually benefit from your vitamin D intake, it’s also important to get enough of the other vitamins and minerals that help your body absorb and utilize vitamin D. These include vitamin A, vitamin K, zinc, boron, and, most importantly, magnesium. Eating beans, nuts, and fish can help you get enough of these essential nutrients.
The Benefits of Vitamin D Supplements
Not sure if eating shrimp scampi and standing out in the sun for fifteen minutes is getting enough vitamin D into your system? It is difficult to tell exactly how much vitamin D you’re getting when you go the natural route, and constantly testing your levels is obviously impractical. That’s why supplements can be especially helpful when you’re trying to track your actual vitamin D intake or recover from a deficiency.
Supplements are the easiest way to quickly increase vitamin D levels, and they are the only way to know exactly how much vitamin D you’re adding to your body. Even if you’re sunbathing regularly, everybody produces different amounts when exposed to the sun. You can’t know for sure how much vitamin D you’re naturally producing, and inviting a sunburn by staying out for extended periods of time is hardly the optimal way to go.
By incorporating supplements into your diet, you can control exactly how much vitamin D you get each day, ensuring a consistent and measurable intake with no guesswork involved.
How Much is Too Much?
The recommended daily intake of vitamin D is 400 international units (IU) for infants less than one year old, 600 IU for children, adults, and pregnant women, and 800 IU for adults over 71 years old. If you have a vitamin D deficiency, your doctor may recommend increasing the amount until your levels are restored to where they should be.
On the opposite end of the spectrum, excessive consumption of vitamin D can be harmful. Overdosing can cause hypercalcemia, which can lead to calcium deposits in your organs and soft tissues, which can be damaging and painful.
Because of this, it’s important to take high-quality supplements with a known and consistent dosage when you’re trying to increase vitamin D levels. Of course, you always want to consult with your doctor, before making any significant changes to your diet or vitamin intake.
Don’t Let a Vitamin D Deficiency Keep You Down
It’s always a good thing to get key vitamins and nutrients the natural way, but when you’ve been diagnosed with a vitamin D deficiency, it’s a good indicator that your lifestyle just isn’t bringing you into contact with the foods and sunlight you need to keep your vitamin D levels up without help.
The truth is that many of us just don’t find it easy to spend time outside, while the sun is out. Obligations to our jobs, families, education, and other responsibilities of modern life don’t leave us with many opportunities to step out and let our skin convert UV rays into vitamin D. Climate, skin sensitivity, and other factors can also work against us here.
Diet can help, but with seafood and eggs being the best natural food sources for vitamin D, vegetarians and vegans are at a huge disadvantage. Even if you do consume meat and fish, you’d have to eat a heck of a lot of salmon and tuna every day to eat your way out of a vitamin D deficiency.
If you really need to increase vitamin D levels fast, a high-quality, natural supplement is likely to be your best bet. You’ll know exactly how much you’re getting and can get your levels back up quickly while working on the lifestyle habits that will keep you from falling into a deficiency again.
Are you getting enough vitamin D? You might think so, but unless you consistently eat a balanced diet, get sunlight exposure, and take supplemental nutrients, you may not get enough vitamin D. You may even have a vitamin D deficiency. In fact, the Centers for Disease Control and Prevention (CDC) estimates that approximately 30 to 40 percent of the United States population doesn’t get enough of this critical micronutrient. This is of importance to all of us as vitamin D has a significant impact on your overall health and well-being.
What Is Vitamin D?
Vitamin D is an important, fat-soluble vitamin that’s crucial for good health. There are two types of vitamin D: vitamin D2, or ergocalciferol, and vitamin D3, or cholecalciferol. Vitamin D2 is found in some supplements and fortified foods. Vitamin D3 is what the body produces from exposure to the sun’s ultraviolet rays, and, compared to D2, vitamin D3 is more readily absorbed and used by the body. That’s one of the features that distinguishes vitamin D from other micronutrients like vitamins A, B, and C – the human body creates it after direct exposure to sunlight, which is why it is often referred to as the “sunshine vitamin.”
The Role of Vitamin D in Your Body
The brain, bones, immune system, and virtually every other cell in the body have specific receptors for vitamin D and require it in order to function at peak efficiency. Vitamin D supports bone health and helps prevent childhood diseases like bone-softening rickets and old-age diseases like osteoporosis and osteomalacia. But vitamin D’s importance goes beyond our bones. In 1903, Danish physician Niels Finsen was awarded the Nobel Prize for his pioneering treatment of tuberculosis with ultraviolet light. And while it was unknown at the time why Finsen’s “heliotherapy” worked so well, scientists now understand that vitamin D and calcitriol played an important role in its success.
In a 2011 study, Oxford University researchers discovered that vitamin D directly influences over 200 genes, including many that have are implicated in autoimmune disorders, cardiovascular disease, and even cancer. Other studies are now showing the role of the micronutrient in promoting bone health, heart health, and the immune system. This is why having adequate levels of D3 circulating in your blood is so important for optimal health. According to the Vitamin D Council, adequate levels are in the range of 40-80 ng/mL.
How Much Vitamin D Does Your Body Need?
The recommended daily allowance for vitamin D is the minimum daily intake necessary to support bone health. Some scenarios, like pregnancy or health certain conditions, may require more. The recommendations are provided in international units (IUs). For reference, one microgram is equivalent to 40 IU.
|0 – 12 months||400 IU|
|1 – 70 years||600 IU|
|70+ years||800 IU|
|Pregnant women||600 IU|
|Breastfeeding women||600 IU|
Symptoms of Vitamin D Deficiency
- Muscle weakness
- Bone aches
If you don’t get enough vitamin D on a regular basis, you could experience vitamin D deficiency. The symptoms of vitamin D deficiency are subtle. While some people may experience muscle weakness, fatigue, bone aches, or just general feelings of malaise, the vast majority of people likely won’t be able to gauge their vitamin D levels without a blood test – especially in the early days of a deficiency. Many symptoms, like high blood pressure, increased risk of infections, and bladder issues, are chalked up to other health concerns.
Most people won’t have any symptoms of vitamin D deficiency.
Chronic vitamin D deficiency will affect nearly every aspect of your well-being. Some of the more serious diseases linked to consistently low vitamin D levels include cardiovascular disease, osteoporosis, autoimmune disorders, diabetes, and a host of neurological conditions. New research also shows that adequate vitamin D levels are crucial to a healthy pregnancy and it helps the developing baby avoid health issues later on in life, too.
If you suspect you may be vitamin D deficient, get tested. Vitamin D levels can be evaluated with a blood test. Normal blood levels are within the 40-80 ng/mL range. Be sure to ask your doctor for the 25-hydroxy vitamin D blood test during your annual physical to ensure your readings are accurate. A result of 20 ng/mL or less could result in increased risk for mood disorders, cognitive impairment, and periodontal disease, among others.
Causes of Vitamin D Deficiency & Who Is At Risk
Vitamin D deficiency, or even low vitamin D levels, can occur for a variety of reasons. Many people don’t get enough sun exposure. Some people don’t get enough vitamin D in their diet, which can be tricky, as there aren’t many foods that are a good natural source of vitamin D. Certain health conditions, such as being overweight, can affect vitamin D levels, as can being older, breastfeeding, and other situations.
Little or No Sun Exposure
People who don’t get enough exposure to sunlight, whether it be by staying indoors, living in an area with inconsistent sunlight, or only venturing outside with sunscreen, are at risk for low vitamin d levels, and even vitamin d deficiency. Clouds, shade, windows, and sunscreen all block the UV rays that prompt your body to begin vitamin D production. All year long, you should try to find time to get a little sunlight on your skin.
Certain Dietary Restrictions
There aren’t many foods that are natural sources of vitamin D, so it’s easy to fall short of your vitamin d requirements because of your diet. Some foods are fortified with vitamin D but it’s usually in the form of vitamin D2. Vegans, vegetarians, and anyone who doesn’t consume fish, dairy, or the other animal foods that do provide a measure of vitamin D may also find themselves lacking in the vitamin D department.
Obesity is a big risk factor for vitamin D deficiency. The body draws calcitriol from the body’s fat cells. If you are overweight, it is more difficult for your fat cells to release sufficient levels of this micronutrient to circulate in the blood.
The nutrient content of breast milk is related to the mother’s nutritional status. If she’s low on vitamin D (or any other nutrient, for that matter) her breast milk will be too. When you consider that infants don’t, and shouldn’t, spend much time in direct sunlight, it’s no wonder that they may be at risk for vitamin D deficiency. Vitamin D supplementation is often recommended during infancy, but check with your healthcare provider to ensure the right serving and protocol.
The process of getting older can present many challenges and having low vitamin D levels is one of them. As people age, it’s harder for their skin to produce vitamin D as efficiently as it used to. When you combine that with the fact that many older adults spend more time indoors, it’s easy to understand why they need to be especially vigilant about maintaining adequate vitamin D levels (and their overall nutrient levels in general).
People With More Melanin
People with a darker skin tone may have difficulty reaching peak vitamin D levels as a result of higher levels of the pigment melanin. With darker skin tone, more exposure to sunlight is necessary for the body to make adequate amounts of the sunshine vitamin.
Individuals with Certain Diseases
There are many health conditions that can cause or exacerbate low vitamin D levels or vitamin D deficiency, or that are correlated with low levels, including cardiovascular disease, cancer, hypertension, and obesity. Digestive ailments like inflammatory bowel disease or celiac disease that impair nutrient absorption often affect the body’s ability to absorb dietary sources of vitamin D. It’s also common for people with digestive conditions to follow a diet that may not consistently provide the full spectrum of nutrients their body requires. Additionally, diseases that affect the liver can lead to low vitamin D levels.
Remedies for Vitamin D Deficiency
Like most health challenges, the best way to fix the issue depends on what’s causing it. If you don’t spend enough time in the sun, start finding time to do this. Take inventory of your nutritional intake. If you’re not getting enough vitamin D in your diet (and there’s a good chance you’re not), either add foods that provide it or consider a supplement.
Most of us are conditioned never to leave the house without a thick coat of sunscreen. But a little sun on your skin isn’t a bad thing. In fact, in order for your body to produce vitamin D, it’s a necessary thing. You can help raise your vitamin D levels with relatively little exposure, it’s not required to tan or burn. Of course, how much is enough (and how much is too much) depends on where you live, the time of year, and your skin tone. Experts suggest staying in the sun for about half the time it would normally take for you to turn a little pink. And, remember, the more skin you can expose to the sun’s rays, the more vitamin D you’ll produce.
Vitamin D Foods
- Fortified Orange Juice
- Fortified Milk and Yogurt
There are not many foods that are a good, natural source of vitamin D. Some types of fish and other animal-based food like liver, cheese, and eggs contain vitamin D, but it’s not a large amount and for people who follow a plant-based diet, those are not suitable options anyway. Some varieties of mushrooms provide vitamin D. Infant formula and processed food that’s been fortified with nutrients is another source of vitamin D. However, generally speaking, food, on its own, does not provide enough vitamin D for most people.
Although the best source of vitamin D is your body’s own production, it’s not always easy to get a healthy serving of sunlight, especially during the winter months. But you can help maintain healthy vitamin D levels with supplementation. The Institute of Medicine recommends 600 IUs of D3 per day for most people – but suggests 800 IU for those over 70 years of age to help promote bone health. For those who are experiencing low vitamin D levels, healthcare experts may also recommend a supplement that provides 4,000 to 10,000 IUs. I recommend Suntrex® D3 if you need a regular, consistent source of high-quality vitamin D that has 5,000 IUs per serving.
Often times vitamin D supplements are recommended for pregnant women and infant children to help bolster their vitamin D levels. Although there are general recommendations, it’s best to rely on personalized guidance from a healthcare provider to determine the appropriate and healthy dose for your situation.
Can You Take Too Much Vitamin D?
While supplementation can help maintain sufficient vitamin D levels, be careful not to overdo it. Vitamin D is a fat-soluble vitamin. It is stored in the body’s fat cells and can become toxic if levels grow too high, leading to a condition called hypercalcemia, which is a severe accumulation of calcium in the blood that may result in gastrointestinal distress and kidney issues. If you’re taking more than 10,000 IUs per day, work closely with your healthcare provider to monitor your levels and ensure they stay in the healthy range.
What Nutrients Complement Vitamin D?
Considering the profound impact it has on one’s health, vitamin D sounds a bit like a miracle micronutrient, but it does not work alone. Scientists have discovered that other vitamins and nutrients, including vitamin A, boron, zinc, vitamin K, and magnesium are instrumental in ensuring that vitamin D levels stay normal and consistent. It just goes to show that following a healthy, balanced diet that provides a complete fill of the recommended daily allowance of all nutrients is the best overall strategy to bolster your efforts to maintain optimal health.
Points to Remember
With so many studies touting vitamin D’s role in maintaining good health and discouraging health ailments, it is important to make sure you have a healthy level of circulating vitamin D in your blood at every age and every stage of life. If you want to live life to the fullest – and avoid those nagging everyday aches and pains – a little bit of sunshine, a few tweaks to your diet, and the right vitamin D supplements can help ensure you are reaching your highest health potential.
Are you cognizant and aware of your vitamin D needs and intake? What insight can you offer? Leave a comment below and share your thoughts with us.
- ” Vitamin D Status: United States, 2001–2006.” National Center for Health Statistics. The Centers for Disease Control and Prevention. Published Mar 2011. Accessed 12 Apr 2018.
- Jain, RB. “Recent Vitamin D Data from NHANES: Variability, Trends, Deficiency and Sufficiency Rates, and Assay Compatibility Issues.” Journal of Advanced Nutrition and Human Metabolism. Published 2016. Accessed 22 July 2018.
- Haughton LA, Reinhold V. “The Case Against Ergocalciferol (Vitamin D2) as a Vitamin Supplement.” The American Journal of Clinical Nutrition. Published 1 October 2006. Accessed 22 July 2018.
- Kato S. “The Function of Vitamin D Receptor in Vitamin D Action.” J Biochem. 2000 May;127(5):717-722. Accessed 11 Apr 2019.
- “Niels Ryberg Finsen – Biographical.” NobelPrize.org. Published 2014. Accessed 22 July 2018.
- “Vitamin D Linked to Autoimmune and Cancer Disease Genes, Underscoring Risks of Deficiency.” Genome Research. CSH Press. Published 24 August 2010. Accessed 22 July 2018.
- “For Health Professionals: Position Statement on Supplementation, Blood Levels, and Sun Exposure.” The Vitamin D Council. Accessed 22 July 2018.
- Kheiri B, et al. “Vitamin D Deficiency and Risk of Cardiovascular Diseases: A Narrative Review.” Clinical Hypertension. BMC. Published 22 June 2018. Accessed 22 July 2018.
- Hollis BW, Wagner CL. “New insights into the vitamin D requirements during pregnancy.” Bone Research. Nature. Published 29 August 2017. Accessed 22 July 2018.
- Forrest K, Stuhldreher W. “Prevalence and Correlates of Vitamin D Deficiency in US Adults.” Nutrition Research. Science Direct. Published January 2011. Accessed 22 July 2018.
- “How Do I Get the Vitamin D My Body Needs?” The Vitamin D Council. Accessed 22 July 2018.
- News Staff. “IOM Updates Guidance on Vitamin D, Calcium.” AAFP.org. Published 1 December 2010. Accessed 22 July 2018.
- “Vitamin D and Other Vitamins and Minerals.” The Vitamin D Council. Accessed 22 July 2018.
†Results may vary. Information and statements made are for education purposes and are not intended to replace the advice of your doctor. If you have a severe medical condition or health concern, see your physician.
Managing Rheumatoid Arthritis: 5 Easy Ways to Boost Vitamin D Intake
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If you have rheumatoid arthritis (RA) — or if you’re at risk for developing this inflammatory type of arthritis — it may be time to start paying attention to your vitamin D intake.
According to a November 2017 study conducted at the University of Birmingham in the U.K., maintaining sufficient vitamin D intake may help prevent or delay the onset of inflammatory health conditions like RA. For people who already have RA, the study’s researchers propose that high doses of vitamin D might be necessary.
“Vitamin D is actually a hormone that plays a critical role in regulating the immune system,” says Sonya Angelone, MS, RDN, a registered dietitian based in San Francisco and a spokesperson for the Academy of Nutrition and Dietetics. “And RA is a condition that results from problems with the immune system.”
According to the Office of Dietary Supplements, adults should aim to get 600 IU of vitamin D daily — though your doctor may recommend you get more, especially if you have RA.
However, most people with RA aren’t getting enough of this essential nutrient. Vitamin D deficiency is common among people with RA, and low levels of vitamin D can exacerbate RA symptoms and even cause bones to become brittle. What’s more, certain RA medications, like oral steroids, can further contribute to vitamin D deficiency. In fact, those who take oral corticosteroids for RA or other health conditions are twice as likely to have a vitamin D deficiency as those who don’t take any corticosteroids, according to research from Albert Einstein College of Medicine of Yeshiva University in New York City.
The good news is that getting the vitamin D you need may help lessen the severity of your RA and prevent bone loss.
How to Get More Vitamin D
Making sure you’re getting enough vitamin D is an important part of keeping your bones healthy. Start by talking to your doctor about having your vitamin D levels checked. If you’re deficient in vitamin D, your doctor will probably recommend ways to boost your vitamin D intake, which may include:
Spending more time outside The Arthritis Foundation recommends spending 10 to 15 minutes in the sun every other day, and possibly longer for those with darker skin. Be careful, however, because time spent in the sun can increase your risk of skin cancer. According to the Skin Cancer Foundation, a limited amount of vitamin D can be obtained from exposure to the sun’s ultraviolet (UV) radiation, and the health risks of UV exposure are still great. If you live in a climate where you’re unable to get sun exposure, talk to your doctor about using a UV lamp, though the health risks of UV exposure still apply.
Sitting by a window Just make sure it’s open, as most window panes block the kind of sunlight that promotes the production of vitamin D.
Eating more fish Focus on fish that’s high in vitamin D. Angelone suggests:
- Cod liver oil — 1 teaspoon has 453 IU of vitamin D
- Salmon — 3 ounces has 447 IU
- Tuna — 3 ounces has 154 IU
- Sardines — 2 fillets have 46 IU
And raw fish has more vitamin D than cooked, so don’t be shy about eating sushi.
Incorporating more vitamin D-fortified foods in your diet Angelone suggests eating more of these vitamin D-fortified foods:
- Fortified orange juice — 1 cup has 137 IU
- Eggs — 1 large egg has 41 IU
- Fortified cereals — 1 cup has 40 IU
- Mushrooms — 1 cup has 2 IU
Taking a vitamin D supplement If you’re vitamin D deficient, it’s likely that your doctor will recommend a vitamin D supplement. Says Angelone, vitamin D supplementation can help improve disease activity for people with RA.
Vitamin D and your health: Breaking old rules, raising new hopes
Updated: May 17, 2019Published: February, 2007
Vitamin D was discovered in 1920, culminating the long search for a way to cure rickets, a painful childhood bone disease. Within a decade, the fortification of foods with vitamin D was under way, and rickets became rare in the United States. But solving the problem of rickets was only the beginning of research into vitamin D. Research results suggest that vitamin D may have a role in other aspects of human health.
Breaking the old rules
Vitamin D is one of the 13 vitamins discovered in the early 20th century by doctors studying nutritional deficiency diseases. Ever since, scientists have defined vitamins as organic (carbon-containing) chemicals that must be obtained from dietary sources because they are not produced by the body’s tissues. Vitamins play a crucial role in our body’s metabolism, but only tiny amounts are needed to fill that role.
Although vitamin D is firmly enshrined as one of the four fat-soluble vitamins, it is not technically a vitamin. True, it’s essential for health, and only minuscule amounts are required. But it breaks the other rules for vitamins because it’s produced in the human body, it’s absent from all natural foods except fish and egg yolks, and even when it’s obtained from foods, it must be transformed by the body before it can do any good.
As our habits change, most of us cannot rely on our bodies to produce vitamin D the old-fashioned way. Instead, we increasingly depend on artificially fortified foods and pills to provide this vital nutrient. Coming full circle in the modern world, this substance may actually come to fit the technical definition of a vitamin.
What is vitamin D?
Vitamin D is not one chemical but many. The natural type is produced in the skin from a universally present form of cholesterol, 7-dehydrocholesterol. Sunlight is the key: Its ultraviolet B (UVB) energy converts the precursor to vitamin D3. In contrast, most dietary supplements are manufactured by exposing a plant sterol to ultraviolet energy, thus producing vitamin D2. Because their function is almost identical, D2 and D3 are lumped together under the name vitamin D — but neither will function until the body works its magic (see figure).
How your body makes vitamin D
The sun’s energy turns a chemical in your skin into vitamin D3, which is carried to your liver and then your kidneys to transform it to active vitamin D.
The first stop is in the liver, where vitamin D picks up extra oxygen and hydrogen molecules to become 25-hydroxyvitamin D, or 25(OH)D. This is the chemical that doctors usually measure to diagnose vitamin D deficiencies. But although 25(OH)D is used for diagnosis, it can’t function until it travels to the kidney. There it acquires a final pair of oxygen and hydrogen molecules to become 1,25 dihydroxyvitamin D; scientists know this active form of the vitamin as 1,25(OH)2D, or calcitriol, but for ordinary folks the name vitamin D is accurate enough.
How it works
Vitamin D’s best-known role is to keep bones healthy by increasing the intestinal absorption of calcium. Without enough vitamin D, the body can only absorb 10% to 15% of dietary calcium, but 30% to 40% absorption is the rule when vitamin reserves are normal. A lack of vitamin D in children causes rickets; in adults, it causes osteomalacia. Both bone diseases are now rare in the United States, but another is on the rise — osteoporosis, the “thin bone” disease that leads to fractures and spinal deformities.
Low levels of vitamin D lead to low bone calcium stores, increasing the risk of fractures. If vitamin D did nothing more than protect bones, it would still be essential. But researchers have begun to accumulate evidence that it may do much more. In fact, many of the body’s tissues contain vitamin D receptors, proteins that bind to vitamin D. In the intestines, the receptors capture vitamin D, enabling efficient calcium absorption. But similar receptors are also present in many other organs, from the prostate to the heart, blood vessels, muscles, and endocrine glands. And work in progress suggests that good things happen when vitamin D binds to these receptors. The main requirement is to have enough vitamin D, but many Americans don’t.
Vitamin D deficiencies
Vitamin D deficiencies were rare when most men rolled up their sleeves to work in sunny fields. But as work shifted from farms to offices, that changed. Because pigmentation can reduce vitamin D production in the skin by over 90%, nonwhite populations are at particular risk. Deficiencies are also common in patients with intestinal disorders that limit absorption of fat and those with kidney or liver diseases that reduce the conversion of vitamin D to its active form, calcitriol (1,25(OH)2D). In addition, certain medications reduce the availability or activity of vitamin D. And even in healthy people, advancing age is linked to an increased risk of vitamin D deficiency.
Although standards vary, most experts agree that levels of 25(OH)D below 20 ng/ml (nanograms per milliliter) reflect clear-cut vitamin D inadequacy, while levels between 20 and 30 ng/ml are borderline.
A number of factors can play a role. Limited exposure to sunlight heads the list. Except during the short summer months, people who live at latitudes above 37 degrees north or below 37 degrees south of the equator don’t get enough UVB energy from the sun to make all the vitamin D they need. The same is true for people who spend most of their time indoors and for those of us who avoid sunshine and use sunscreens to protect our skin from the harmful effects of ultraviolet radiation (see box below). It’s an example of an unforeseen consequence of wise behavior, but you can enjoy sun protection and strong bones, too, by taking vitamin supplements.
Like politicians, doctors often have to compromise; when it comes to sunshine, most pols promise blue skies, while most docs turn out to be the shady guys — or, at least, sunscreen advocates.
Sunlight contains two forms of radiant energy, ultraviolet A (UVA) and ultraviolet B (UVB). UVB provides the energy your skin needs to make vitamin D, but that energy can burn the skin and increase the cell damage that leads to cancer. UVA also contributes to skin damage and premature aging.
To protect yourself, avoid the summer sunshine, especially between 10 a.m. and 2 p.m. Whenever possible, wear a large-brimmed hat and a tightly woven, dark-colored long-sleeve shirt and long pants when you go out in the sun.
But summer garb is usually lightweight and exposes a lot of skin. That’s where a sunscreen comes in. Look for a product with an SPF of at least 15; fair-skinned people would be wise to shoot for 30 or higher. But since SPFs apply only to UVB, look for a “broad spectrum” sunscreen that also protects against UVA; most contain titanium dioxide, zinc oxide, or avobenzone (also known as Parsol 1789). Above all, apply your sunscreen early, often, and liberally.
These many factors explain why vitamin D deficiencies are shockingly common in the United States. Although standards vary, most experts agree that levels of 25(OH)D below 20 ng/ml (nanograms per milliliter) reflect clear-cut vitamin D inadequacy, while levels between 20 and 30 ng/ml are borderline. Using similar criteria, American researchers have reported deficiencies in 42% of African American women aged 15 to 49, in 41% of non-hospitalized patients aged 49 to 83, and in up to 57% of hospitalized patients. And low levels of vitamin D are common even in apparently healthy young adults; in one study, more than a third of people between the ages of 18 and 29 were deficient.
Numbers can never tell the whole story, but in this case, “D-ficiencies” add up to a wide range of health concerns.
Osteoporosis and fractures
It’s a paradox: Skeletal health is the best-known contribution of vitamin D, but it has also become the most controversial. Although doctors agree that vitamin D deficiency increases the risk of osteoporosis and fractures, they disagree about the benefits and optimal dosage of supplements.
Without enough vitamin D, the intestines cannot efficiently absorb calcium. But because blood calcium is critical for neuromuscular and cardiac function, the body does not allow levels to fall. Instead, it pours out parathyroid hormone, which mobilizes calcium from bone. Blood calcium levels remain normal, so your heart and nerves keep working nicely. But your bones bear the brunt: As bone calcium density falls, bones become weak and fracture-prone.
Most studies show that a lack of vitamin D increases the risk of osteoporosis and the likelihood of hip and other non-spinal fractures. But there is considerable disagreement about how much supplements reduce the risk of fractures. Some studies include only women, others both men and women; some include only frail, elderly, or institutionalized subjects, others physically active people; some use vitamin D alone, others a combination of D and varying doses of calcium; and some administer 400 international units (IU) of vitamin D a day, others up to 800 IU a day.
Some men mistakenly dismiss osteoporosis as a women’s worry, but none fail to recognize the importance of prostate cancer.
Vitamin D has an important role in regulating cell growth. Laboratory experiments suggest that it helps prevent the unrestrained cell multiplication that characterizes cancer by reducing cell division, restricting tumor blood supply (angiogenesis), increasing the death of cancer cells (apoptosis), and limiting the spread of cancer cells (metastasis). Like many human tissues, the prostate has an abundant supply of vitamin D receptors. And, like some other tissues, it also contains enzymes that convert biologically inactive 25(OH)D into the active form of the vitamin, 1,25(OH)2D. These enzymes are much more active in normal prostate cells than in prostate cancer cells.
Do the results from these experiments translate into clinically important effects? Possibly.
In 1998, Harvard’s Health Professionals Follow-up Study of 47,781 men reported that a high consumption of calcium supplements was associated with an increased risk of advanced prostate cancer. The risk was greatest in men getting more than 2,000 mg of calcium a day from a combination of supplements and food. Since then, other studies have confirmed a link between very high levels of calcium intake and increased risk, but they have exonerated dietary calcium consumption. The Harvard scientists speculate that the problem is not calcium itself but a relative lack of active vitamin D.
The risk of colon cancer, breast cancer, and other malignancies appears to rise in populations at latitudes far from the equator. Sun exposure and vitamin D levels may be part of the explanation. A recent clinical trial looking at a daily 1,000 IU vitamin D supplement did not show a decreased risk of cancer, but it was associated with a decreased risk of cancer death.
It’s more reason to be hopeful about vitamin D, and more reason to call for additional research.
“D” right amount
Until 1997, the recommended dietary allowance (RDA) for vitamin D was 200 IU for all adults. Faced with growing evidence of vitamin D deficiencies in Americans, the RDA for 51- to 70-year-olds was increased to 400 IU, and to 600 IU for people older than 70.
Is more better? New research suggests that it is, and many authorities are recommending 800 or even 1,000 IU a day. Remember, though, that you can get too much of a good thing. Like the other fat-soluble vitamins, vitamin D is stored in the body’s adipose (fat) tissue. That means your body can mobilize its own reserves if your daily intake falters temporarily — but it also means that excessive doses of vitamin D can build up to toxic levels. At those extremes, vitamin D can raise blood calcium to levels that can cause grogginess, constipation, and even death. But it takes massive overdosing to produce toxicity, and doses up to 2,000 IU a day are considered safe.
You can make your vitamin D the old-fashioned way, by exposing your skin to UVB radiation in sunlight. It doesn’t take much, but people living north of the 37-degree-latitude line — roughly the imaginary line between Philadelphia and San Francisco — can’t get enough UVB in winter to do the trick. And many others will find it all too easy to overdose on UVB, increasing their risk of malignant melanomas and other skin cancers, as well as wrinkles and premature skin aging. All in all, most doctors recommend avoiding sunlight (see box) and getting vitamin D by mouth.
Diet can help, but it’s very hard to approach the new goals with food alone. Fish and shellfish provide natural vitamin D (oily fish are best), but you’ll have to eat about 5 ounces of salmon, 7 ounces of halibut, 30 ounces of cod, or nearly two 8-ounce cans of tuna to get just 400 IU. An egg yolk will provide about 20 IU, but since it also contains nearly a day’s quota of cholesterol, you can’t very well use eggs to fill your tank with D. Other foods have even less D, which is why manufacturers fortify milk, some yogurt, some orange juice, and many cereals with vitamin D. In general, a serving will provide about 100 IU; that means drinking a quart of fortified milk to get 400 IU.
Most people require supplements to get the vitamin D they need. It’s the main benefit of a daily multivitamin; most provide 400 IU. Remember to read the labels carefully so you won’t get too little or too much. And although cod liver oil is rich in vitamin D, it has too much vitamin A for regular use.
New light on the sunshine vitamin
It used to be simple: just get a “healthy” tan and your body will make all the vitamin D it needs. Desk jobs and sunscreen have changed all that, just as research is underlining the importance of vitamin D and suggesting its possible role in preventing many health problems. That makes vitamin D a dilemma of modern life that has a modern solution: eating fish and drinking some low-fat fortified milk, along with judicious doses of vitamin D supplements.
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