The nutrient helps prevent 17 types of cancer and may be a treatment for autoimmune diseases.
Vitamin
D is an essential fat-soluble steroid hormone for the human body, and its
absence can provide a host of complications.
After
all, it controls 270 genes, including cells of the cardiovascular system. The
primary source of vitamin D production is sun exposure because ultraviolet
B-type rays (UVB) can activate the synthesis of this substance.
Some
foods, especially fatty fish, are sources of vitamin D, but the sun is
responsible for 80 to 90 percent of the body's vitamin.
It
can also be produced in laboratories and given as a supplement when there is a
deficiency and the prevention and treatment of several diseases.
With
the increase of coronavirus cases in the world, vitamin D has been a
much-discussed subject.
Some
studies reveal the potential of vitamin D for the immune system and protection
against respiratory diseases. However, the Ministry of Health says that there
is still no proof of the effects of vitamin D on virus prevention.
This
substance also acts in hormone secretion and several non-transmissible chronic
diseases; metabolic syndrome has type 2 diabetes as one of its components.
Vitamin
D was named this way in 1922 because, at that time, it was believed that it
could only be obtained through food.
It
was named D because it was the fourth substance discovered. After vitamins A,
B, and C. Beginning in the 1970s, researchers found that the body could
synthesize vitamin D, i.e., a hormone, not a vitamin.
Functions
One
of the main functions of vitamin D is to help the body absorb calcium, one of
the minerals essential for normal bone formation. In infancy, it is used to
produce and maintain the skeletal system.
Vitamin D also plays an indispensable role in organ maintenance. Some of the functions
in which it intervenes are:
- Anti-aging functions.
- May have antitumor properties.
- It intervenes in the processes of the immune system.
- Regulation of calcium and phosphorus levels in the blood.
- Participates in skeletal development by contributing to bone formation and mineralization.
- It promotes the intestinal absorption of phosphorus and calcium from food and the reabsorption of calcium at the renal level.
How
Much Vitamin D Do We Need?
- Infants 0 to 1 year old: 400 to 1000 IUI/day
- From 1 to 18 years old: 600 to 1000 IUI/day
- Adults and pregnant women (general population and at-risk): 600 to 2000IU/day.
What
to Do to Get Vitamin D?
Although it is present in foods of animal origin, these foods do not have the amount of vitamin D that the body needs.
Therefore, to avoid vitamin D deficiency, it is
essential to get 15 to 20 minutes of sunshine a day. Arms and legs should be
exposed because the amount of vitamin D obtained is proportional to the amount
of skin exposed.
When exposing yourself to the sun to get the vitamin, it is important not to use sunscreen. To have an idea, sunscreen factor 8 inhibits the retention of vitamin D in 95%, and a factor higher than this practically zeroes the production of the substance.
After the recommended 15 to 20 minutes to get the
vitamin, use sunscreen to avoid skin cancer.
This is due to the fact that ultraviolet B-type rays (UVB), which are capable of activating vitamin D synthesis, cannot pass through glass.
This is because
ultraviolet B-type rays (UVB), which are capable of activating vitamin D
synthesis, cannot pass through glass.
Sun exposure in the recommended manner will provide 10,000 units of vitamin D. Since sun exposure will already provide reasonable amounts of the substance.
A health professional must analyze the individual's needs to determine if sun exposure alone is enough or if a diet rich in the substance or supplementation is needed.
Foods
That Contain Vitamin D
Vitamin D is produced by the body with direct exposure to the sun (not obtained in enclosed spaces through windows).
Exposure for 10 to 15 minutes three times a
week usually meets the body's need for this vitamin. However, if people do not
live in very sunny places they will have to rely on diet and supplements.
The main food sources where it can be found are:
- Meat
- Mushrooms
- Fish liver oils, milk, eggs and butter
- Many foods are fortified with vitamins, such as breakfast cereals, orange juice or yogurt.
- Oily fish: they are the best option. Tuna, mackerel and salmon contain large amounts of vitamin D.
Vitamin
D Deficiency
Vitamin
D deficiency can cause many health problems. A lack of it increases the risk of
heart problems, osteoporosis, cancer, cold and flu, and autoimmune diseases
such as multiple sclerosis and type 1 diabetes.
In
pregnant women, vitamin D deficiency increases the risk of miscarriage, favors
pre-eclampsia, and raises the child's chances of being autistic.
Unfortunately,
about 80 percent of people who live in an urban environment are deficient in
vitamin D. This is because they spend significant periods indoors and are not
exposed to the sun.
However,
the deficiency can be reversed. This can be corrected by supplementation, but
only after medical advice and/or by sunbathing without sunscreen on the arms
and legs for fifteen to twenty minutes every day.
Signs of Vitamin D Deficiency
Depression: Psychiatrists at UT Southwestern Medical Center, Texas, USA, have found a link between low vitamin D levels and depression.
The experts, however, have not yet
arrived at an exact amount of the nutrient that can decrease the symptoms of
depression.
Bone
problems: Vitamin D is necessary for the absorption of calcium by
the bones. People with vitamin D deficiency get up to 30 percent less calcium
from their diet.
Heart disease: A lack of vitamin D can lead to the accumulation of calcium in the arteries, favoring the risk of plaque formation.
Thus, the
chances of developing cardiovascular diseases such as heart failure, stroke,
and heart attack are higher in people with vitamin D deficiency.
Risk
in pregnancy: Vitamin D is crucial for pregnant women. In the first
trimester, a lack of it can lead to miscarriages. In addition, in late
pregnancy, a lack of vitamin D can cause pre-eclampsia and increase the child's
chances of being autistic.
Diabetes: The fact that vitamin D influences the production of renin is also interesting for preventing diabetes because the lack of this substance favors the disease.
In addition, the production of insulin by the pancreas requires the participation of vitamin D.
Impaired
muscle strength: Vitamin D contributes to muscle strength, so its absence
leads to loss of muscle strength and increases the risk of falls and fractures.
Autoimmune diseases: Vitamin D is an immunoregulator that selectively inhibits the immune response that causes the body to react against itself.
Some of the
autoimmune diseases treated with high doses of vitamin D are multiple
sclerosis, rheumatoid arthritis, and eye problems.
Cancer: The
lack of vitamin D favors 17 types of cancer, such as breast, prostate, and
melanoma. In addition, vitamin D also promotes the self-destruction of cancer
cells.
Colds
and flu: Children with vitamin D deficiency are more likely to
develop respiratory infections. Adults with lower amounts of vitamin D get more
colds and respiratory tract problems.
Risk
of premature death: Research published in the Archives of Internal Medicine
found that taking vitamin D supplements decreased the risk of all-cause
mortality by 7%.
Vitamin
D and COVID-19
One
well-known effect of vitamin D is its influence on white blood cells, the
active agents of our immunity. Good levels of the vitamin prevent the cells
from releasing inflammatory cytokines in large quantities.
The latest research shows that COVID-19 causes just the same thing: excess release of these cytokines. In conjunction with white blood cell activity, the effects are very dangerous.
With the right vitamin D, your body will be better able to
handle the situation if the virus infects you.
Vitamin
D Supplementation
The main source of vitamin D in humans is the production of the skin. When it receives the sun's UVB-type rays, the skin synthesizes about 80 to 90 percent of the body's vitamin D.
Only 10% to 20% of all circulating vitamin D comes
from food. This is because food does not contain large amounts of the
substance. When daily sun exposure is insufficient - as in people who spend all
day indoors - supplementation can be a way out.
Vitamin
D supplements can be used in cases of vitamin D deficiency or the treatment of
some diseases. The lack of the nutrient is verified after a blood test.
It is important to emphasize that supplements can only be taken after medical advice to consume these extra doses. In some treatments, vitamin D overdoses are recommended, i.e., an amount beyond what is usually recommended.
In these
cases, the consumption is always made under medical supervision, and it is
necessary to observe how much calcium and liquids the person will ingest. The
consumption of the mineral may need to be reduced, and that of liquids
increased.
The elderly and supplements: Older people produce less vitamin D in response to sun exposure because of age-related metabolic issues.
The amount of the substance produced in a 70-year-old is average a quarter of that synthesized by a 20-year-old.
Therefore, it is worthwhile for older people
to talk to their doctors about the possibility of taking vitamin D supplements.
Recommendation: When
taking vitamin D supplements to avoid health problems, especially in the
kidneys, besides medical follow-up, it is essential to stay hydrated and
maintain a balanced diet.
Excess Vitamin D
Too much can cause the intestine to absorb calcium that is not needed, which can lead to high levels of this mineral in the blood and promote the following situations:
- Increased likelihood of kidney stones.
- Chance of developing kidney damage.
- Increased likelihood of confusion and disorientation.
- Believed to cause poor appetite and unintentional weight loss.
- Deposits of this mineral in soft tissues such as tendons, heart and lungs.
- May be associated with the development of gastrointestinal problems such as nausea, vomiting or constipation.
Interactions
When consumed in the recommended amounts, vitamin D does not interact with any other substance. In rare cases of intoxication, it can lead to high calcium absorption.
The safe amount for daily consumption, even without medical advice, is up to 2,000 IU. Higher doses can be prescribed with complete safety but should ideally be done under the supervision of a health professional.