If you do not spend time outside each day or if you do not eat enough foods that contain vitamin D, there is a chance you might not be getting enough vitamin D.
According to the National Institutes of Health, vitamin D is an important nutrient that allows your body to absorb calcium to keep your bones strong. Consuming enough vitamin D and calcium can help you avoid developing osteoporosis, which makes your bones weaker and causes you to be more prone to broken bones. Low levels of vitamin D can also cause you to develop osteomalacia, which causes muscle weakness and bone pain.
Vitamin D helps your muscles and nerves function properly. Vitamin D also strengthens your immune system to help it fight against viruses and bacteria.
Adults 19-70 years of age need 15 micrograms (600 IU) of vitamin D per day, and adults 71 years or older need 20 micrograms (800 IU) of vitamin D daily.
How Do I Get Vitamin D?
The best way to get vitamin D is from the sun. However, it is important to note that ultraviolet rays from the sun can cause skin cancer, so it is recommended to use sunscreen that has a sun protection factor (SPF) of at least 15 when you are outside. Wearing sunscreen will not significantly decrease your body’s ability to make vitamin D from the sun.
The following may decrease the amount of vitamin D you get from the sun:
- Having dark skin
- Age
- Smog or other air pollution
- Clouds
You can also get vitamin D from certain foods or drinks. Most food items and beverages with vitamin D in them are fortified, meaning vitamin D has been added to them. Your body will convert the vitamin D you consume into the active form of vitamin D that your body can use. Some fortified foods and beverages include the following:
- Milk (cow, soy, almond and oat milk)
- Cereal
- Orange juice
- Yogurt
- Margarine
- Fatty fish (mackerel, tuna, salmon and trout)
Food items that provide smaller amounts of vitamin D include:
- Mushrooms
- Cheese
- Egg yolks
- Beef liver
How Do I Find Out if I Have Enough Vitamin D?
Regardless of the amount of time you spend outside or the foods you eat, you can still be deficient in vitamin D. You can visit your primary care provider, who can order blood work to check your vitamin D level. Your provider will then explain your lab results to you.
The desired level of vitamin D in your blood is between 50-125 nanomoles per liter. If your vitamin D level is below 30 nanomoles per liter, it is too low, and you likely need a vitamin D supplement. If your vitamin D level is above 125 nanomoles per liter, it is too high.
About 25% of people need a vitamin D supplement. The following groups of people may be more likely to have lower levels of vitamin D requiring supplementation:
- People who have had weight loss surgery
- People with obesity
- People who have ulcerative colitis, celiac disease or Chron’s disease
- People with dark skin
- People who do not expose their skin to the sun
- Older adults
- Infants who are breastfed
If your vitamin D level is low, your provider may prescribe a high-strength supplement or have you take a lower-strength over-the-counter supplement. Your provider may prescribe vitamin D 50,000 International Units (IU) weekly or recommend that you take 400-5,000 IU daily of an over-the counter product, depending on your current vitamin D levels.
Over-the-counter supplements are available in gummy, capsule or liquid form. It is best to take your vitamin D supplement in the morning with higher fat containing food to assist with absorption.
Vitamin D supplements are available in two forms: D3 and D2. Most often, vitamin D3 is preferred due to its higher potency and its closer resemblance to the form naturally produced in the body.
If your blood work reveals you have low amounts of other nutrients, your provider may prescribe or recommend that you take a supplement that combines vitamin D and the other nutrients you have too little of in your body.
It is important to follow your provider’s recommendations regarding whether you should take a vitamin D supplement. It is possible to consume too much vitamin D. This can lead to increased calcium in your blood and the following side effects:
- Vomiting
- Nausea
- Confusion
- Muscle weakness
- Reduced appetite
- Excessive urination
- Dehydration
- Kidney stones
- Irregular heartbeat
- Kidney failure
- Death
It is also important to know that vitamin D supplements can interact with certain medications, including:
- Thiazide diuretics
- Steroids
- Medications that lower cholesterol
- Orlistat, a weight-loss medication
- Aluminum containing medications
- Certain anticonvulsants (phenytoin and phenobarbital)
Let your primary care provider and pharmacist know about all the medications you take. This information can help them confirm if a vitamin D supplement is right for you or if any adjustments should be made to your other medications.
If you’re unsure that you’re getting the adequate amount of vitamin D, consult with your doctor or a dietician. If you need a primary care provider, visit UofL Physicians – Primary Care or call 502-588-4343 to find a provider near you.
