Top vitamin D supplements advice for absorption

Sometimes patients have adequate intake and exposure, yet the top vitamin D supplements advice has to do with effectively absorbing this key vitamin

Vitamin D supports bone growth and strength, reduces inflammation, and promotes optimal immune function. It also aids the body with calcium and phosphate absorption, which helps avoid muscle spasms and cramps, but what is the top vitamin D supplements advice for absorption for patients in terms of what to take and when?

Although it is the second most-consumed dietary supplement for all age groups—with a multivitamin or multimineral being the first, according to the Centers for Disease Control and Prevention—the question is: Are your patients’ bodies absorbing this important nutrient when taken as a supplement?

Top vitamin D supplements advice: the absorption process

The Office of Dietary Supplements (ODS) explains that vitamin D must go through a two-step process before it can be used by the body. This process is necessary whether the vitamin is consumed in supplemental form, or if it is obtained via food or the sun.

The first step is a chemical process in which the vitamin D is converted into 25-hydroxyvitamin D or calcidiol. The second step also uses enzymes to serve as a catalyst, this time converting the calcidiol into calcitriol or 1,25-dihyroxyvitamin D. The first conversion occurs in the liver and the second in the kidney.

While the human body is typically efficient at converting vitamins and minerals into a useable form, research reveals that vitamin D deficiency is “widely prevalent,” impacting up to one billion people worldwide. The reasons for this are many.

Factors leading to vitamin D absorption issues

Of course, vitamin D deficiency can occur if dietary intake is too low or if there isn’t much exposure to the sun. However, sometimes people have adequate intake and exposure, yet the top vitamin D supplements advice has to do with effectively absorbing this key vitamin.

Harvard Health Publishing reports that gut health and the presence of digestive conditions can both potentially thwart the body’s usage of vitamin D. Gut health matters because gastric juices and digestive secretions can impact the amount of vitamin absorbed. Digestive conditions that can lower vitamin D absorption include celiac disease, Crohn’s, and cystic fibrosis.

Harvard adds that if the liver and kidneys aren’t functioning appropriately, this can hinder vitamin D absorption as well. In some cases, this is due to not being able to support the two-step conversion process necessary to convert this vitamin into its usable form. Other times, certain secretions aren’t adequate to support optimal absorption, such as if the liver doesn’t produce enough bile.

The ODS further indicates that vitamin D deficiency is also a concern for people who’ve had gastric bypass surgery. This procedure involves bypassing a portion of the upper intestine, which happens to be the same portion in which vitamin D is absorbed. Thus, vitamin D absorption is reduced.

Signs of inefficient vitamin D absorption

One way to determine whether the body is efficiently converting vitamin D into its usable form is with a blood test. It’s also helpful to watch for signs of a potential vitamin D deficiency, which the Cleveland Clinic states include:

• Feelings of fatigue and tiredness
• Bone pain, which can be differentiated from joint or muscle pain by being present even when the patient is still or not moving
• Muscle weakness, aches, or cramps
• Changes in mood, such as in increase in depression

Improving vitamin D availability

If it’s determined that the body isn’t adequately converting vitamin D into its usable form, or if patients want to maximize the amount of vitamin D that they are consuming, the top vitamin D supplements advice for patients has to do with assisting this process.

A 2017 overview of factors influencing the absorption of vitamin D shares that taking this vitamin with the biggest meal of the day has been found to raise the serum level of calcidiol (the first step in the conversion process) by roughly 50%. Taking it with foods that contain a bit of fat helps as well. Conversely, consuming vitamin D with foods high in fiber can potentially reduce its bioavailability, though this is still somewhat unclear.

It’s also possible that a patient’s other medications may be inhibiting the body’s ability to convert and use vitamin D. The ODS shares that some medications negatively interact with vitamin D supplements, including a few weight-loss drugs, drugs designed to lower cholesterol, diuretics, and corticosteroid medications.

If this is a concern, patients should discuss this issue with their doctors to better determine options for improving vitamin D absorption without negatively impacting their health.