Vitamin D (sunshine vitamin or calciferol) performs other life-changing functions, such as reducing cancer and seasonal flu risk, promoting a healthy heart and good night’s sleep, maintaining cognitive skills in older adults, helping with weight loss, preventing type 2 diabetes, and protecting your oral health.
One of the pointers to its importance to the body is the presence of vitamin D receptors in many organs and tissues.
Calciferol is a fat-soluble vitamin you can get via a few foods or fortified items like cereals and milk and vitamin D supplementation.
In this article, we deep dive into what this essential nutrient can do for your body.
We also discuss the symptoms of vitamin D deficiency, factors that affect this, how common it is, and how much of this nutrient you need daily.
Here are some ways vitamin D aids your body:
1. Vitamin D promotes bone health and muscle strength
Without Vitamin D, your body cannot absorb calcium and phosphorus in your small intestines. Furthermore, adequate calciferol in your body regulates the concentration of calcium and phosphorus.
Optimal levels of these two nutrients are important for bone mineralization and growth.
Vitamin D may also help maintain muscle strength. This is especially important in older adults who are at risk of substantial disability and death due to falling as a result of muscle weakness.
A study of multiple clinical trials found that vitamin D supplements helped older adults reduce their risk of falling by 19%.
Vitamin D is essential for osteoblasts and osteoclasts to perform their duties. Osteoblasts are cells that help form new bones and ensure existing bones grow and develop.
Osteoclasts, on the other hand, help fix damaged and unhealthy bone tissues by dissolving them and replacing them with new and healthier ones.
Aside from building bones, your body needs a continuous dose of calcium to prevent osteomalacia, a condition caused by prolonged vitamin D deficiency.
Osteomalacia is similar to rickets, the softening of the bones. It increases the risk of suffering bone fractures. The population more at risk of this condition are older adults.
2. Vitamin D may reduce your risk of getting cancer
Although inconclusive, evidence suggests a strong correlation between serum concentration of vitamin D in your blood and the risk of some cancers.
A study examining the relationship between colon cancer deaths and vitamin D levels concluded that vitamin D can be a protective agent against colon cancer.
The researchers found more colon cancer deaths among subjects who stayed at higher altitudes compared with those who lived at lower altitudes.
The vitamin D level of people staying in higher altitudes is lower because the sun’s UVB rays are fainter at those altitudes.
As such, they cannot produce enough calciferol even with adequate sun exposure.
Different epidemiological studies have also shown a strong correlation between vitamin D and reduced risks of getting specific cancers, such as pancreatic, prostate, and colorectal cancer.
Research also suggests vitamin D can increase a cancer patient’s chances of survival. Scientists observed a lower death rate (13%) in the cohort assigned vitamin D supplements versus those given the placebo.
3. Vitamin D may reduce the risk of seasonal flu and other infections
A randomized controlled trial in Japan followed 340 students for four months during the winter flu season. Fifty percent of the study participants took 1,200 IU of vitamin D supplementation, while the others received a placebo.
The researchers observed a 40% lower type A influenza rate among the group that took vitamin D than those in the placebo group. The study found no difference between the two groups for type B influenza.
While taking vitamin D supplements can help reduce the risk of getting the flu, we recommend also receiving your flu shots, notwithstanding.
Vitamin D can also help you prevent other acute respiratory infections. One study found that taking vitamin D “protected against acute respiratory tract infection overall.”
Other studies have also shown that low levels of the sunshine vitamin may increase the risk of getting tuberculosis and other autoimmune conditions.
4. Vitamin D promotes a healthy heart
We stated earlier how many organs and tissues in the body have vitamin D receptors. The heart is no exception. Vitamin D regulates the cells that contribute to conditions like hardening of the arteries (atherosclerosis).
Additionally, the vitamin prevents high blood pressure by keeping your arteries flexible and relaxed.
A follow-up study that tracked 50,000 men for ten years found that the men who had the lowest level of serum vitamin D (25(OH)D) were 100 percent more likely to have a heart attack than the men with the highest 25(OH)D levels.
Other epidemiological studies have also observed this negative correlation between 25(OH)D levels and the chances of getting a stroke or other negative heart events.
5. Vitamin D helps maintain cognitive ability
The brain contains multiple vitamin D receptors, which explains why vitamin D concentrations in the brain can affect its health.
In a study of over 430,000 participants, researchers found that individuals with less than 25 nmol/L of vitamin D in their blood were 54% more likely to suffer from dementia versus those with at least 50 nmol/L.
Another study in which scientists explored the data of 290 deceased individuals who participated in the Rush Memory and Aging Project found a link between dementia and vitamin D.
Per the research, individuals with higher vitamin D levels in their brains had a 25% to 33% reduced odds of getting dementia or other cognitive impairment at their last visit to the Rush Memory and Aging Project center.
6. Vitamin D promotes a healthy mood and good sleep
Serotonin has many benefits and functions in your body. For starters, it controls your mood. Serotonin also helps regulate your sleep pattern and sexual desire.
Many studies have shown that optimal levels of vitamin D boost the concentration of serotonin in the brain. As such, you may feel moody when you have a vitamin D deficiency, which may put you at risk of mood disorders.
The National Institute of Mental Health (NIMH) reports that seasonal affective disorder (SAD) may become worse if you have vitamin D deficiency.
This is because vitamin D has been identified in the body’s ability to produce serotonin. Research suggests that reduced serotonin activity is one of the leading causes of SAD.
Another systematic review and meta‐analysis of other trials concluded that taking 2,000+IU per day of vitamin D is likely to reduce depressive symptoms.
7. Vitamin D may help with weight loss
Several studies have painted a strong correlation between obesity and vitamin D levels. One study explored this correlation in a clinical trial involving 50 overweight and obese women.
The study gave one-half of the participants a 50,000 IU dose of vitamin D per week. The other group received a placebo for six weeks. After six weeks, group members who received supplemental vitamin D had significantly reduced weight, body mass index, and waist circumference than the other group.
A meta-analysis of 11 trials also concluded that vitamin D had the desired effect on the participants’ weight.
Obese and overweight participants experienced lower BMI and waist circumference.
One of the hypotheses for why vitamin D may help with weight loss is that vitamin D suppresses the parathyroid hormone (PTH).
The parathyroid glands primarily produce the PTH to regulate calcium concentration, but PTH also affects fat accumulation in the body.
8. Vitamin D helps prevent type 2 diabetes
A review of various research studies has strongly linked vitamin D with reducing the risk of diabetes.
One such study followed 83,000 women without diabetes at baseline for 20 years.
The researchers found that women who took the highest dose of vitamin D supplements reduced their odds of developing type 2 diabetes by 13% versus those who consumed smaller amounts of vitamin D.
Another clinical trial with 2,423 adults with prediabetes came to the same conclusion. The participants were divided into two groups.
One group received 4000 IU of vitamin D daily for 24 months, while the other group took a placebo for the same period.
The incidence rate of diabetes in the first group was lower after 2.5 years compared to the group that received the placebo. The blood level of serum vitamin D in the vitamin D group was also almost twice more, 54.3 ng/mL compared to 28.8 ng/mL in the placebo group.
9. Vitamin D boosts good oral health
Vitamin D is also essential for your teeth, particularly helping to prevent tooth decay and periodontitis. Periodontitis is a gum infection that can eat the gum around your teeth and cause them to fall off. It can also damage the bone that keeps your teeth in place.
In a study that examined the association between serum 25-hydroxyvitamin D levels and dental caries, the researchers found that United States adults with severe vitamin D deficiencies (<25 nmol/ml) were 2.48 likelier to damage their teeth with the presence of dental caries against those with normal adequate levels of 25(OH)D (≥75 nmol/mL).
Those with deficient and insufficient levels were also 1.29 and 1.43 times more likely to get dental caries versus the group with normal vitamin D levels.
In another cross-sectional study, researchers explored the association of vitamin D with periodontitis. They found that patients with periodontitis and coronary heart disease (CHD)had lower levels of 25(OH)D compared to patients with only CHD.
10. Vitamin D can help prevent acne
A meta-analysis of 13 research studies with 1,362 acne patients and 1,081 healthy participants found that the vitamin D blood levels in the former were “significantly lower” than in the latter.
The report also noted that acne severity negatively correlated with vitamin D levels. That is, the lower the vitamin D levels, the worse the acne is. The conclusion was that “vitamin D might be involved in the pathogenesis (origination of a disease) of acne.”
Another study came to the same conclusions as above. The research, however, ran a subsequent trial where vitamin-D-deficient acne patients received 1000 IU/day for two months. After two months, the patients who received vitamin D supplements experienced “improvement in inflammatory lesions.”
These studies point to the potential of vitamin D in preventing acne and helping to improve acne inflammation.
11. Vitamin D regulates your innate immunity
Innate immunity defines your body’s first line of defense against invading pathogens. Several studies have pinpointed vitamin D as a regulator of this critical body function.
Increasing the level of vitamin D in the blood promotes the production of “defensin β2 and cathelicidin antimicrobial peptide (CAMP),” which helps the body fight bacterial infections. Also, 1,25(OH)2D3 (serum concentration of vitamin D) increases “increases chemotaxis, autophagy, and phagolysosomal fusion of innate immune cells.”
The bottom line of these scientific terms is that vitamin D plays a prominent role in ensuring your first line of defense has all it needs to prosper and protect you.
For example, the results from one research study suggested that vitamin D could be playing a vital role in the body’s natural resistance to HIV-1, the first discovered variant of the human immunodeficiency virus.
What sets vitamin D apart from other nutrients?
There are significant differences between vitamin D and other nutrients.
Vitamin D is the only one of the 13 essential vitamins the body can synthesize by itself. The body can produce vitamin D when you expose yourself to an adequate amount of sunlight.
The form of vitamin D that the body produces after sunlight exposure is D3. The body cannot produce the D2 variant.
Vitamin D is also generally referred to as a hormone because it contributes to how many cells and organs function.
According to the National Academy of Sciences, “Vitamin D, first identified as a vitamin early in the 20th century, is now recognized as a prohormone.”
What distinguishes vitamin D from vitamin D3?
There are two variants of vitamin D, Vitamin D2 and D3. D2 is also known as ergocalciferol, while vitamin D3 is the same as cholecalciferol. Of the two variants, only D3 can be produced when you expose your body to UVB rays from the sun.
You can get vitamin D2 primarily from plant sources and vitamin D3 from animal sources like fatty fish. Vitamin D2 and D3 are mostly the same, except for their side chain structure. They are absorbed the same way in the body.
Both forms of vitamin D are available as dietary supplements. However, research suggests that vitamin D3 works better for higher storage of the vitamin. One study found that vitamin D3 induced 83% greater storage of vitamin D versus vitamin D2.
Vitamin D3 is more effective and active than D2.
You can get your supplemental vitamin D3 needs in our Organic Vitamin D3 and K2 With Spirulina Capsules packed with 10,000 IU of D3 per capsule.
What are the symptoms of vitamin D deficiency?
Many symptoms may indicate that you have a deficit of vitamin D. "May" is the operative word here.
It's important to clarify that many symptoms are synonymous with other nutrient deficiencies and ailments. It is, therefore, not a given that vitamin D is solely responsible for feeling any of the symptoms below.
Daily supplemental vitamin D intake has been proven to be safe and helpful. Notwithstanding, always consult with your doctor before treating any serious medical condition.
Here are some symptoms to look out for:
Muscle weakness or pain
Low levels of vitamin D may be the reason you’re experiencing muscle weakness or pain. We’ve established how vitamin D may help strengthen your muscles.
Per some scientific evidence, vitamin D deficiency is a potential cause of muscle pain.
Bone loss or weakness
Vitamin D is vital for the growth and repair of bones in your body because it helps the body absorb calcium and phosphorus. Optimal levels of vitamin D mean maximum absorption of calcium needed for bone needs.
Low vitamin D levels over a long period may lead to low bone mineral density, a situation where your bone continues to lose essential minerals. People with low bone mineral density suffer from pain and weakness.
This condition can increase the chances of experiencing a bone fracture, especially in older adults.
Rickets in children
Rickets, the bone-weakening sickness in children, is a clear indication of vitamin D deficiency. Because they lack vitamin D, their bones harden and thus become deformed.
Rickets can be traced to nursing mothers with vitamin D deficiency. All baby foods are required to include a minimum amount of vitamin D.
Osteomalacia
Osteomalacia is like rickets but in adults. It’s typified by weak and soft bones and due to prolonged vitamin D deficiency. Osteomalacia is reversible through supplementation.
Poor sleep hygiene
Many studies associate poor sleep hygiene with vitamin D deficiency. Vitamin D helps the body produce serotonin, which, in turn, aids the body’s ability to regulate its day and night rhythm.
Other symptoms
Other potential symptoms of vitamin D deficiency include:
- Poor wound healing
- Fatigue
- Depression or moodiness
- Loss of appetite
- Regular recurring illness or infections
- Pale skin
- Hair loss
- Weight gain
- anxiety
Is vitamin D deficiency common?
Vitamin D deficiency prevalence is more common than you think. Older estimates say over 1 billion people globally live with vitamin D deficiency.
About 35% of adults are vitamin D deficient in the United States. Additionally, approximately 50% of children aged 1-5 and 70% of children aged 6-11 have vitamin D stores levels below the recommended values.
Vitamin D deficiency is also more common in certain ethnic groups than in others. For example, African Americans are almost thrice as likely to be deficient than non-Hispanic Whites.
About 20% of White adults in the United States have blood levels of vitamin D below 50 nmol/L. The number is 75% for Black adults.
Factors that affect the risk of developing a vitamin D deficiency
Many factors can make you more at risk of developing vitamin D deficiency compared to the next person. These factors include:
Dark skin
According to the Centers for Disease Control and Prevention (CDC), “Non-Hispanic whites have higher concentrations of 25(OH)D than Mexican Americans, who themselves have higher concentrations than non-Hispanic Blacks.”
One of the reasons for this is the presence of melanin in the epidermal layer of darker skin. Melanin limits the body’s vitamin D production from sunlight.
Despite being more at risk of vitamin D deficiency, Black adults are less susceptible to osteoporosis than White adults.
Exclusively breastfed babies
Babies exclusively breastfed are at risk of suffering from rickets. This danger is even more pronounced in babies fed by mothers without enough vitamin D.
Typically, breast milk provides less than the recommended vitamin D intake for infants, 25 to 78 IU.
Although infants can also produce vitamin D from sunlight exposure, pediatricians recommend not keeping babies less than six months under direct sunlight.
As such, the American Academy of Pediatrics (AAP) recommends giving exclusively breastfed babies a vitamin D supplement of 400 IU per day till the baby is weaned.
The AAP also suggests giving the same dosage to babies not breastfed but still consuming formula or milk fortified with less than 1,000 mL/day of vitamin D.
In both cases, you do not need to give the child vitamin D supplements if the infant consumes over 1,000 mL/day of vitamin D-fortified formula or milk.
Vitamin D3 liquid drops supplement fortified with vitamin K2 by WhyNotNatural is perfect for babies on exclusive breastfeeding.
Two drops of this product provide your infants (0-12 months) with the daily required 400 IU of vitamin D. It’s safe, contains no fillers, and can be taken with or without food.
People with obesity
Earlier, we mentioned how vitamin D is linked with weight loss. So, it’s not surprising that people who are obese are more likely to be vitamin D deficient.
According to the National Institutes of Health (NIH), people who have a body mass index of 30 or more are more predisposed to having lower levels of vitamin D in their blood than individuals with lesser BMIs.
It’s important to stress that fat or obesity does not inhibit the body’s ability to produce vitamin D.
However, vitamin D can accumulate in subcutaneous (below the skin) fatty tissues. When this happens, the body may find it hard to extract the vitamin D when needed.
Consequently, obese people are advised to take higher doses of vitamin D to ensure there’s a desirable level in the blood, like in those with regular body weight.
Older adults
Older adults are likely to be vitamin D deficient or insufficient for two reasons. Firstly, the body’s ability to produce vitamin D after sunlight exposure reduces with age. It’s one of the reasons experts advise adults above 71 years to take 33% more vitamin D than other adults.
The second reason is that older adults are likely to be less mobile. That is, they may likely stay indoors, especially for older adults with waning health. Hence, they enjoy less and less exposure to the sun.
This limitation, including the body’s reduced efficiency in synthesizing calciferol from the sun, puts older adults at risk.
Location and lifestyle
Research published in the Global Pediatric Health (GPH) deduced that vitamin D levels were significantly negatively correlated with altitude.
The higher the location, the more likelihood of lower vitamin D levels. Thus, your vitamin D levels may suffer if you live in a hilly or mountainous area.
Lifestyle habits also contribute to your risks. For example, people who wear overalls and cover most of their body due to cultural or religious reasons will likely not synthesize enough vitamin D even if they spend quality time in the sun.
People who apply sunscreen may also be at risk of vitamin D deficiency. Additionally, people who work from home or whose jobs keep them indoors all day are equally at risk.
Lastly, vegans, vegetarians, or people with lactose intolerance are at risk of vitamin deficiency, primarily because they do not take vitamin D-fortified dairy products like milk.
People with inflammatory bowel disease
Inflammatory bowel diseases like ulcerative colitis, cystic fibrosis, Crohn’s disease, and liver disease are associated with fat malabsorption. Fat malabsorption is a condition that affects how the body digests fat.
When this happens, the body also finds it difficult to absorb vitamin D. We’ve established that vitamin D is fat soluble. Vitamin D absorption heavily depends on the body’s ability to absorb dietary fat.
Thus, you may be at risk if you endure any of the above conditions.
People who have undergone gastric bypass surgery
Gastric bypass surgery involves removing the upper part of the small intestine. Coincidentally, this is also the region where vitamin D is absorbed into the body.
While the body can still absorb calciferol from fat stores, it’s usually not enough to increase vitamin D levels to the required level.
People with kidney disease
The kidney helps your body absorb vitamin D. The kidney converts the inactive form of vitamin D to the active form.
As such, individuals with chronic kidney disease or end-stage renal disease have severe vitamin D deficiency because they’re incapable of converting vitamin D to its active form, irrespective of the amount consumed.
How much vitamin D do you need?
According to the Office of Dietary Supplements at NIH, the daily recommended dietary allowance (RDA) for adults, pregnant individuals, and children aged between 1-13 years is 600 IU. The RDA for infants between 0-12 months is 400 IU and 800 IU for adults above 70 years.
It’s worth noting that when scientists measure vitamin D deficiency, it’s not based on how much you consume but on the levels in your blood.
You can consume 2,000 IU of the vitamin daily and still be deficient because you have one or more of the risk factors we identified in the section above.
Therefore, rather than intake value, the real number you should examine is your serum concentration (25(OH)D), which is the level of active vitamin D in your blood.
However, the tricky part is that many experts are divided on what the adequate level of 25(OH)D should be.
What is serum concentration, and what levels should I aspire for?
Serum concentration is the biomarker for how much vitamin D exposure your body has. It is measured by nanomoles per liter (nmol/L) or nanograms per milliliter (ng/mL).
Per the National Academies of Sciences, Engineering, and Medicine (NASEM), serum concentration below 12 ng/mL puts you at risk of vitamin D deficiency.
Having 12 to less than 20 ng/mL is also considered to be inadequate for your bone and health needs.
NASEM considers 20 ng/mL and above as ideal. But even that value is a bit contentious within the medical sphere.
The Endocrine Society (ES), however, defines deficiency as having less than 30 ng/mL. Per the ES, the adequate range is 40 to 60 ng/mL to “maximize the effect of vitamin D on calcium, bone, and muscle metabolism.”
Consequently, the ES recommends the following RDA guidelines:
- Infants (0-12 months): 400 to 1000 IU daily
- Children and adolescents (1-18 years): 600 to 1000 IU daily
- Adults: 1500 to 2000 IU daily
What are the sources of vitamin D?
Foods naturally containing vitamin D are few and far between. The list includes trout, tuna, mackerel, beef liver, fish liver oils, cheese, egg yolks, swordfish, sardines, and mushrooms. Cod liver oil provides 1,360 IU of vitamin D per serving. The next best source is trout, at 645 IU per serving.
Only a few foods can naturally provide vitamin D in abundant quantities, mostly fatty fish like tuna and salmon and fish liver oils. Other sources have small amounts of the vitamin.
Because of the limited food options to naturally get vitamin D, many other food sources are fortified with the vitamin.
Milk is fortified with 120 IU per cup of vitamin D (usually the D3 variant) in the United States. Milk from plant sources is also typically fortified with equal amounts of vitamin D.
Fortifying milk with vitamin D is compulsory in Canada but voluntary in the United States, so it’s not a given that the milk you buy is fortified.
Many breakfast cereals are also fortified, along with products like orange juice and yogurt. However, products derived from milk, like butter, cheese, and ice cream are not fortified. It’s important to remember this distinction when assessing your dietary intake.
All infant milk manufacturers in the United States must also fortify their products with 40–100 IU of vitamin D. In Canada, the mandated level for baby food is 40-80 IU.
Can I get enough vitamin D from only the sun?
Based on factors like time of the day, duration of exposure, sunscreen use, and percentage of body exposed, you can most likely only get some of your vitamin D needs through sunlight exposure.
Ideally, you should be able to get enough vitamin D from sun exposure. But that is only half of the story. Many factors must be in place to maximize vitamin D production.
Factors like your skin color, time of the year, location, health status, and duration of exposure come into play.
A report examined vitamin D production from sunlight exposure in Boston and Miami.
The findings showed that a person in Miami with 25% of their body exposed to the sun at noon would need to spend only three minutes in the sun to produce sufficient amounts of vitamin D. For Boston with the same conditions, they would need 23 minutes.
With about 5% of the body exposed during winter, the duration required balloons to be about 2 hours for the person in Boston.
This doesn’t yet account for other factors like skin color. People in Boston can also not make adequate vitamin D for four months out of the year.
Although the body stores vitamin D in fat cells, most people are deficient by late winter.
Then, when you consider the risk of getting skin cancer, you can ask if it’s necessary to be exposed to the sun for too long.
Other factors like your schedule, cultural and religious beliefs, age, and habits like wearing sunscreen also significantly affect how much vitamin D you can absorb from the sun.
Wearing sunscreen can reduce how much vitamin D you get from the sun by up to 90%, depending on how much you use, the SPF value, and how many parts of your body are covered.
How the body produces vitamin D from the sun
When the sun’s UVB light hits your skin, the vitamin D receptor cells in your skin convert 7-dehydrocholesterol to vitamin D3 through a series of reactions.
The absorbed vitamin is stored in your body’s fat cells, where it remains inactive. When needed, the body pulls the vitamin D into your kidney and liver. There, it is converted to its active form, calcitriol, through a process called hydroxylation.
Note that standing behind a window and feeling the heat of the sun cannot help you produce vitamin D.
The glass prevents the entry of the sun’s UVB rays, which is the key element in synthesizing vitamin D on your skin.
Which form of vitamin D is best for the body?
There are two variants of vitamin D, D2 and D3. Research suggests that vitamin D3 is more effective in improving low vitamin D levels.
You can get vitamin D3 from the sun and animal sources like the flesh of fatty fish, while D2 is mostly available through plants. Both variants are stored in their inactive form (calcidiol) and made active (calcitriol) in the kidney when the body needs it.
Many studies concluded that D3 is better if you want to increase vitamin D levels in your body. However, some studies proved otherwise.
We recommend taking vitamin D3 supplements based on the above research. However, ensure you take it alone without mixing it with vitamin D2. Why?
New research - still a developing theory - shows that vitamin D2 may counteract the effect of vitamin D3. This study found that the concentration of 25(OH)D3 in the group given vitamin D2 was lower than in the group given no vitamin D supplement.
The results from this study suggest vitamin D2 may be capable of depleting vitamin D3.
Is vitamin D supplement good for the body?
Vitamin D supplement is good for the body because many people do not spend enough time in the sun and consume enough vitamin D-rich food to produce a sufficient amount of vitamin D their body needs. Hence, many foods like milk and some orange juice are fortified.
With limited sources of food that naturally provide vitamin D, you’ll be hard-pressed to eat a balanced diet that gives your body all the calciferol you need for maintaining healthy bones and other important functions.
Additionally, experts suggest going under the sun around midday to shorten your stay and reduce the risk of skin cancer.
But that is only half of the equation because how long you stay under the sun depends on your location and what body parts are exposed.
The bottom line is sun exposure, and food alone cannot provide all the vitamin D you need.
Even babies on breast milk alone are supposed to be on vitamin D supplements (400 IU of vitamin D per day), per the CDC.
That’s why vitamin D supplement is good for your body because it helps you provide enough calciferol for you to experience the many benefits of the vitamin.
Some of these benefits include:
- Improved mood
- Better sleep at night
- Strong bones and muscles
- Reduced cancer mortality
- Protection against seasonal flu and infections
Get our organic vitamin D3 and K2 with Spirulina. It is perfect for supporting a healthy immune system.
Does vitamin D supplement make you sleepy?
Vitamin D by itself does and cannot make you sleepy. That said, vitamin D promotes the production of serotonin. Serotonin can improve the quality of your sleep by keeping you awake longer and helping you fall asleep quickly.
If you’re taking other vitamins or drugs, they may be the cause of your sleepiness.
Excess vitamin C and iron can induce fatigue and make you feel sleepy. Some allergy medications like brompheniramine and hydroxyzine can make you drowsy and heavy-eyed.
It could, overall, also be a coincidence. Perhaps you do not get enough sleep or wake up during the night and find it hard to get back to sleep. In this case, you may need to assess your sleeping environment and control habits like pressing your phone while in bed.
When is the best time to take vitamin D supplements?
There’s no best time to take vitamin D. You should, however, plan around using your vitamin D supplements with your heaviest meal of the day.
You can take your vitamin D supplements any time of the day. No research suggests or indicates a specific period as optimal for vitamin D absorption. We can say, though, that creating a routine helps you stay consistent with whatever supplements you take.
In addition to sticking to a routine, take your vitamin D supplements with your heaviest meal of the day. Bonus points if the meal also contains a high-fat content, which will hasten the absorption of the vitamin D supplements.
One study found that participants who took their vitamin D supplements with their heaviest meal of the day increased their 25(OH)D serum concentration by about 50%.
How long does it take for vitamin D supplements to work?
Consistent vitamin D supplementation will most likely show significant blood level changes after a few weeks, often more than four weeks, based on data from research studies. However, if you’ve suffered vitamin D deficiency for months, it may take up to months to reverse symptoms.
How long it takes for vitamin D supplements to boost your blood levels of 25(OH)D depends on many factors, including dosage, age, amount of vitamin D obtained from food and the sun, certain health conditions, obesity, and consistent intake.
If you’re old and get little sunlight, it might take longer to get the same result as someone younger who gets more sunlight, provided the dosage is the same. So, it’s not exactly a straight line.
One study found that those who checked their vitamin D levels 3-9 months after their initial test showed the biggest increase.
Retests taken just after four weeks showed no significant increase in 25(OH)D.
Another study concluded that “Serum 25(OH)D can be expected to rise by about 1 ng/mL (2.5 nmol/L) for every 100 IU of additional vitamin D each day.”
The key takeaway here is to be consistent in taking a decent amount of vitamin D, at least 2,000 IU D daily.
A doctor with UnityPoint Health, Dr. Molly Ropte, also notes that you can make improvements to your blood levels within three to four months of taking vitamin D supplements.
What is the right dosage of Vitamin D supplements?
There’s no universal dosage for vitamin D supplements. The right dosage for you depends on many factors. Are you trying to maintain optimal levels or resolve severe vitamin D deficiency? The latter requires more dosage than the former. Still, the dosage will depend on personal factors.
Are you obese or suffer from health conditions that limit vitamin D absorption? If you are, you’ll need a bigger dose than someone who isn’t.
Getting decent sunlight exposure can also reduce your dependence on supplements. So, you must also consider your daily habits and schedule to gauge how much vitamin D you’re getting.
Another major factor that affects your supplement needs is your diet. If your diet is not filled with vitamin D-rich foods, you also need a higher dose.
All these suggest that one size doesn’t indeed fit all. It’s really difficult to estimate how much vitamin D supplement you need.
And one of the reasons for this is that vitamin D deficiency doesn’t manifest on the outside immediately. You can’t tell your serum concentration levels till you run a test. Sometimes, it may take a fracture for doctors to catch it.
So, to be better safe than sorry, we recommend staying within the tolerable upper intake level.
As one study puts it: Taking a 30,000 IU dose or less of vitamin D per day for extended periods did not result in intoxication. Intoxication is defined as serum concentration levels of 200 ng/ml (500 nmol/L).
The study concluded that the leading authorities should consider pegging the daily intake level at 10,000 IU.
Thus, this suggests that you can take a vitamin D dosage of 10,000 IU and still be safe, especially if you suffer from insufficiency or deficiency.
Are there risks associated with excessive vitamin D?
Taking more than the required level of vitamin D can lead to toxic levels in your blood with symptoms such as blocked arteries, nausea, weight loss, calcification of soft tissues, loss of appetite, and excessive thirst.
The risk of too much vitamin D is toxicity, which can only come from taking supplements. It’s impossible to get toxicity from sunlight exposure and highly improbable to get it from food.
As with everything we consume, too much can breed issues unintended. The same principle applies to vitamin D intake. Vitamin D toxicity is when blood levels of 25(OH)D lead to adverse effects like:
- Unrestricted absorption of calcium (hypercalcemia) into the bloodstream may lead to the hardening of blood vessels.
- Weight loss
- Anorexia
- Irregular heartbeat
- Nausea
- Vomiting
- Dehydration
- Potential renal failure
That said, the Food and Nutrition Board (FNB) at NASEM acknowledges that you’re unlikely to experience toxicity at a daily vitamin D intake below 250 mcg (10,000 IU).
It’s also worth noting that staying in the sun for 15 minutes with only a bathing suit can produce up to 10,000 to 20,000 IU of vitamin D in White adults living in certain regions.
Yet, they do not experience toxicity despite repeating the same exercise for multiple consecutive days. So, staying within this range is reasonable.
The primary risk of consuming vitamin D is the absorption of calcium. Therefore, you should really avoid taking calcium supplements with vitamin D.
Can vitamin D be ingested simultaneously with other dietary supplements?
Broadly speaking, you can take vitamin D with other dietary supplements, especially fat-soluble ones like vitamins A and K. While you can also take vitamin D with calcium supplements, we advise against it as it can cause calcium to deposit in your blood vessels and other soft tissues.
Calcium can also affect the absorption of other supplements, like zinc, magnesium, and iron.
Is it safe to take vitamin C and vitamin D concurrently?
You can combine vitamin C and vitamin D together when taking your multivitamins. In fact, you’ll be doing your immune system and general health a great service by doing so.
Vitamin C (ascorbic acid) provides many benefits to the body in many ways. It is essential for the immune system to function properly and helps the body to make and repair cells. The body also needs ascorbic acid to absorb iron.
There’s no contraindication if you take vitamin D and vitamin C concurrently.
Check out our 5-in-1 supplement with Vitamins C and D that help fight against recurring urinary tract infections.
Is it safe to take omega 3 with vitamin D?
Taking omega 3 with vitamin D together poses no threat to your health. Taking the two together can help fasten vitamin D absorption because the latter is fat-soluble, and omega 3 is obtained from fish oil. Fish contains both vitamin D and omega 3.
Omega 3 should be a vital part of your diet, whether from food or supplements. Some of its benefits include:
- Lowering your blood pressure
- Reducing the risk of a heart attack or stroke by reducing the amount of triglyceride in your blood.
- Minimizing the risk of developing blood clots
- Reducing the risk of some cancers, Alzheimer’s disease, and dementia.
There’s no scientific record or research stating vitamin D and omega 3 are at odds with one another. So, yes, it’s safe to consume the two together.
Takeaway: Take the right dosage of Vitamin D for a healthy body
Vitamin D can help you in many ways beyond ensuring you have strong bones and muscles.
The sunshine vitamin may also reduce the risk of developing certain cancers, seasonal flu, and other infections. Vitamin D also promotes a healthy heart and may help maintain cognitive ability in old age.
Other benefits include helping with weight loss, promoting good sleep, preventing type 2 diabetes, and protecting your oral health. These benefits are only accruable when you have adequate vitamin D levels in your blood.
While the sun is a great source of vitamin D, many factors prevent many people from depending on it solely. That's why supplements are increasingly a popular option to avoid vitamin D deficiency.
For quality, natural, vegan-friendly, and highly concentrated vitamin D supplements with no preservatives, fillers, artificial additives, or sugar that are easily absorbed and work, visit the Why Not Natural supplement store today.
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