Vitamin D builds your bones and keeps your gut sealed, among many other essential functions - but many children are deficient.
You've likely heard about vitamin D's
important role in maintaining strong bones and teeth. But it also plays several
other important roles to keep your body healthy – including the function of
your gut.
As part
of our research on how a dietary fiber supplement affects bone mass in children
and adolescents, the MetA-Bone Trial, we are also studying gut health.
For this
study, we recruited 213 children and adolescents from South Florida, primarily
Hispanics, though some were Black. Before having them start taking the fiber
supplement, we measured their vitamin D levels to ensure they had adequate
amounts. Surprisingly, we found that 68% of these children had suboptimal
vitamin D levels.
Considering South Florida is an area with
plenty of sunshine year-round, this was both startling and concerning. While
vitamin D can be obtained from foods, most people in the US get this vitamin
primarily from skin exposure to sunlight. For youth approaching or experiencing
puberty – a period of profound physiological changes, including rapid changes
in bone mass – vitamin D deficiency could lead to several health issues.
Connection between vitamin D and health
Vitamin D is involved in so many bodily
functions because there are vitamin D receptors in different organs. These
receptors act like docking stations for vitamin D to bind to and trigger
different effects in the skin, intestine, bone, parathyroid gland, immune
system and pancreas, among others.
Vitamin D
regulates calcium levels in the body, which is key for not only building and
maintaining bone mass but also the basic functioning of the nervous system.
Vitamin D
also stimulates cell differentiation, a process in which cells become
specialised to carry out specific functions. It is also essential to insulin
secretion to control blood sugar levels, blood pressure regulation, muscle
repair and regeneration, immune function and nutrient absorption, among many
other functions.
Vitamin D and gut health
The
vitamin D receptors in your gut improve calcium absorption and strengthen your
intestinal barrier.
The
intestinal barrier is a layered wall that allows your gut to absorb nutrients
and keep out harmful bacteria. This wall is composed of intestinal cells and
proteins called tight junctions that act like bricks sealing these cells
together. Tight junctions play an important role in maintaining the structure
of your intestinal barrier.
Vitamin D
receptors help your gut produce tight junctions to maintain your intestinal
barrier. Research suggests that vitamin D deficiency reduces production of the
receptors the nutrient binds to, subsequently reducing the seal of the
intestinal wall.
This
weakening of the gut barrier may allow substances from the intestine to pass
into the blood, causing inflammation. Disruption of the intestinal barrier is
linked to many diseases, including liver disease, Type 1 diabetes, obesity and
gastrointestinal conditions such as celiac disease, inflammatory bowel disease
and colon cancer.
After discovering that so many of the participants in our MetA-Bone Trial had
suboptimal vitamin D levels, we became interested in understanding how this
nutrient might be affecting their gut health. For this, we also measured the
strength of their intestinal barrier and associated this to their vitamin D
levels in blood.
We found
that children with suboptimal vitamin D levels had a higher risk of damaging
their intestinal barrier compared with children with optimal vitamin D levels.
This finding suggests that even in healthy children, suboptimal levels of
vitamin D may compromise the gut and potentially increase the risk of
developing chronic diseases at an early age.
Getting enough vitamin D
Vitamin D
deficiency is highly prevalent in the U.S. and around the world. Roughly 15.4%
of children and adolescents in the U.S. were vitamin D deficient in 2017. While
vitamin D deficiency has slightly decreased over time in the general U.S.
population, it remains high among teens, especially children with darker skin.
How can you ensure you are getting enough
of this important nutrient?
Only a few foods naturally contain vitamin D. For example, vitamin D is naturally found in fatty fish – such as trout, salmon, cod and tuna – egg yolks and mushrooms.
Vitamin D can also be found in many fortified foods, such as dairy products like milk and cheese, plant-based milks, breakfast cereals, some orange juice brands and infant formulas. Dietary supplements are also good sources of vitamin D.
For most
people in the U.S., Sun exposure is their main source of vitamin D. However,
how much Sun exposure you need depends on several factors, such as the melanin
content of your skin. Melanin is a pigment that protects your skin from ultraviolet
radiation. People with more melanin – and therefore darker skin – produce less
vitamin D from Sun exposure than those with less melanin and may thus require
longer Sun exposure to meet minimum requirements.
Since
excessive ultraviolet radiation is associated with skin cancer, clinicians
typically recommend you meet your vitamin D requirements through foods and
beverages. For healthy children and adults, the recommended dietary allowance
of vitamin D is 600 IU, with an age-based upper limit of no more than 1,000 to
4,000 IU.
You can
usually meet this through a healthy diet that includes a variety of whole and
unprocessed foods.
Researchers
continue to uncover the extensive benefits of vitamin D in the body, supporting
its indispensable role in nutrition and health. For growing children and
adolescents, enough vitamin D is important for healthy development.
No comments:
Post a Comment