Vitamin D, “the sunshine vitamin” that our body produces when we are exposed to sunlight, is essential for our health.
It is essential for bone and tooth health, regulating inflammation, supporting the immune system, and other tasks.
A new report, presented at the American Heart Association Scientific Sessions 2023 conference, suggests that the current recommended daily allowance (RDA) of vitamin D in the U.S. may be too low to reach optimal levels for certain people, particularly those with heart problems.
Thus, researchers from Health among mountainsa healthcare network in the western US, are conducting an ongoing clinical trial to examine this issue.
Their study includes 632 participants who have suffered a heart attack or another type of cardiovascular problem. One group of participants received standard care, while the other received vitamin D supplements as needed to achieve 40 nanograms of vitamin D per milliliter (ng/ml).
Their preliminary results showed that most people needed significant levels of vitamin D supplementation to reach that level.
In fact, 51% of participants needed between 5,000 and 8,000 international units (IU), 10 times more (or more) than the current recommended daily dose of 600 IU for most people.
And 14.6% of participants needed 10,000 IU or more to achieve optimal vitamin D levels.
Previous studies found a link between low vitamin D levels and an increased risk of heart attack or stroke. “However, the reasons behind this association are unclear,” Dr. Cheng-Han Chena cardiologist who was not involved in the current study, told Medical News Today.
Some experts believe that “vitamin D receptors on cells throughout the vascular system are involved in inflammation of blood vessels, which in turn could promote heart disease,” Chen added.
If their ongoing study “shows that achieving a vitamin D level of [more than] “40 ng/mL reduces the risk of adverse cardiovascular events, doctors should be more proactive in testing and treating low vitamin D levels,” the study author said. Dr. Heidi Maycardiovascular epidemiologist at Intermountain Health.
“We are currently following the participants until there is enough [cardiovascular] events that have occurred so we can compare whether treating low vitamin D levels reduces cardiovascular outcomes compared to not actively treating low vitamin D levels,” May added.
What is vitamin D?
Vitamin D is an essential vitamin that your body produces when your skin is exposed to ultraviolet (UV) rays from sunlight. It can also be found in some foods and supplements.
Research has found that vitamin D plays an important role in the immune system and may reduce the risk of autoimmune diseases such as diabetes, asthma, and rheumatoid arthritis.
It is also essential for bone mineralization, the lifelong process by which minerals (particularly calcium and phosphorus) are added to bone tissue to help it strengthen and grow.
Current recommendations for vitamin D intake are:
- Babies from 0 to 12 months: 400 IU
- Children and adults from 1 to 70 years: 600 IU
- Adults over 70 years of age: 800 IU
- Pregnant or lactating women: 600 IU
Vitamin D from sunlight
Most vitamin D is produced by the body when ultraviolet rays reach the skin; The vitamin is then stored in the body’s fat cells.
People at risk for low vitamin D levels (including people with disabilities, infants, the elderly, and anyone living in far northern or southern latitudes during the winter) are also at risk of losing bone density and increasing the likelihood of fractures.
People with darker skin have more melanin, so less UV light is absorbed to create vitamin D. according to UCLA Health. Therefore, they need more sun exposure to produce vitamin D than lighter-skinned people.
One study found that during the summer, with only 25% of the body exposed to the sun, eight to 10 minutes of midday sun produced the recommended amount of vitamin D.
But in winter, with 10% of the body exposed due to colder temperatures, it takes almost two hours of midday sun exposure to produce enough vitamin D.
vitamin D deficiency
Infancy and childhood, when bone growth is rapid, are important ages to get enough vitamin D. Vitamin D deficiency in children can cause rickets, a softening of bone tissues that can lead to bone and joint deformities. , including bow-legged legs.
Some studies suggest a link between low exposure to vitamin D and an increased risk of allergies in children. For example, children who live closer to the equator have lower rates of allergies and fewer prescriptions for epinephrine auto-injectors (EpiPens).
However, in most people, a short-term vitamin D deficiency does not cause serious symptoms, although chronic deficiencies can cause hypocalcemia (a calcium deficiency disease) or hyperparathyroidism, where the parathyroid glands create a hormonal imbalance, according to Medical news today.
These conditions can lead to bone fragility and osteoporosis; bone-ache; muscle spasms, weakness and pain; fatigue and joint stiffness.
If vitamin D deficiency continues for long periods, it can lead to autoimmune problems; breast, prostate and colon cancer; neurological diseases; infections; and pregnancy complications.
Foods with vitamin D
You probably get most of your vitamin D from exposure to sunlight, but during the winter months, some research suggests that people may benefit from vitamin D supplements.
There are not many foods that contain vitamin D, but those that do include:
- Fatty fish such as salmon, mackerel and tuna.
- egg yolks
- Cheese
- Cow liver
- Fungus
- Milk, cereals, juices and other foods fortified with vitamin D
