Vitamin D deficiency, why does it happen?
Table of contents
- Most common causes of a vitamin D deficiency:
- 1. Not receiving enough sunlight during winter
- 2. Very little exposure to sunlight rays during summer
- 3. Staying inside all the time (for work reasons)
- 4. An excessive use of sun cream
- 5. Vitamin D deficiency in the diet
- 6. The consumption of medications or alcohol
- 7. Overweight
- 8. Old age
- 9. Being bedridden or suffering from a disability
- 10. Vitamin d deficiency caused by disease
- 11. People with dark skin
- Who has the highest risk of suffering a Vitamin D deficiency?
- How to detect a Deficiency of Vitamin D?
Vitamin D is not a common vitamin since it is received in different ways: through the diet and by exposing our skin to sunlight (UVB rays), it transforms into an element that activates when our body needs it.
Up to a 90% of vitamin D is produced in this way. Only between a 5 and 10% of the necessary vitamin D is absorbed through our diet, mainly by eating blue fish, butter, milk, egg yolk, and cheese regularly.
Several studies have shown that approximately between 80 to 90% of the people who live in industrialized and modern countries, suffer from a mild to severe vitamin D deficiency. The reasons why a vitamin D deficiency can occur are varied and can be related to a specific lifestyle and environment. It can also be due to a single factor or a combination of them.
This tends to happen to all those who live above the 42º latitude (north of Rome). During the months of October to March, the sun is too low in these areas and it does not produce enough UVB radiation to be able to penetrate our skin.
Going for a walk during 20 minutes in the winter can be a well-intentioned advise, but it is not enough for the production of vitamin D. Additionally, the environmental pollution of cities prevents the UV rays from reaching our skin.
Generally speaking, the vitamin D reserves that have been acquired during summer will run out and be reduced to a half in two months approximately. Therefore, a lot of people are affected, which makes it more likely to catch a cold, or feeling low or in a bad mood. A winter holiday, of two week in the sun are ideal to restore our body’s vitamin D reserves.
Sunbathing in a swimsuit during 15-20 minutes, three times a week, is enough to obtain the normal Vitamin D amounts. However this is not something that everyone can do, for professional or other reasons. This is why there are a lot of people do not sunbathe enough during the summer.
In fact, it is advisable to be exposed to sunlight in the summer, no matter which latitude you live in.
Anyone who has a job that obliges them to stay inside in closed spaces or to work at night, can not receive the sufficient amount of vitamin D on their way to work and with their skin covered by clothes.
Being in front of the television or computer for many hours is a fact that prevents a lot of people from getting sunlight during the summer. This risk is very high, especially for those who live in big cities, where the opportunity to sunbathe is even more limited.
This fact can be added to the fact that during the winter months we have less exposure to the sun rays, being the most common reason of a shortage of vitamin D in big cities.
Nowadays, we are constantly being warned of the risk of suffering skin cancer or premature ageing if we expose our body to direct sunlight. But this alarm in reality drives us to not sunbathing enough and end up suffering from a vitamin D deficiency.
Even a solar protection factor of 8 will block the production of vitamin D in the dermis in a 95%. The ideal way to proceed would be to expose our skin, only during the first 10-30 minutes, with no sunscreen. This period of time should be adapted to the particular type of skin of each person. The period of time should be chosen so that in no case an erythema will be produced during the sun exposure.
Sun cream must be used to avoid burning the dermis. If you want to stay in the sun for longer with no protection, you can increase the exposure as you are more suntanned.
Maybe the food products that you consume have a very low vitamin D content. Among the most rich sources of vitamin D, we can include:
- 250-300 micrograms in cod liver oil
- 8-25 mcg in smoked eels and herring
- 16 mcg in salmon
- 4 mcg in mackerel
- 3.8 mcg in beef
- 1.7 mcg in beef liver
- 2.9 mcg in eggs (total)
- 1.2 mcg in butter
- 2.5 to 7.5 mcg in margarine enriched with vitamin D
- 1.3 mcg in Gouda cheese
- 0.19 mcg in cottage cheese (40% fat)
- 0.06 to 0.09 mcg in whole milk and yogurt (3.5%)
It has to be taken into account that these amounts are per 100 grams, and not all of these products are consumed in the same amounts. Cod liver oil contains very high amount of vitamin D, but its consumption provides very low quantities of Vitamin D.
On the other hand, the consumption of fatty fish in our latitudes is usually very low. Egg yolks, butter and cheese are frequent in our regular diet, but on a daily basis they are consumed in small quantities, although they appear as one of the foods that most vitamin d provides.
Vegans in particular have a higher risk of suffering from a vitamin d deficiency, because this vitamin tends to be found mainly in food products with an animal origin. Although fungi and avocados contain Vitamin D2, the precursor of vitamin D3.
However, it must be converted by the sunlight on the dermis into vitamin D3.
With a bit of effort one can reach the recommended daily allowance of 5 mcg (200 UI). However this amount is not enough to generate or maintain a healthy level of Vitamin D.
Antidepressants, blood thinners, steroids and medications to treat peptic ulcer disease and epilepsy can inhibit the absorption of the vitamin D we take in our diet. Even those who drink a lot of alcohol may have a higher risk of suffering from a lack of vitamin D. These people should take this vitamin as a supplement.
People with obesity have a lower capacity to generate vitamin D in comparison to those that are not overweight. Studies prove that people who are overweight have, in most cases, a lower value of vitamin D 25(OH)D that thin people.
Being overweight is usually followed by being less exposed to the sunlight and a reduced diet.
As we age our body progressively loses the capacity to synthesize vitamin D from sunlight. At the same time the need to obtain vitamin d increases.
Once we pass the age of 65, the skin produces half of the amount of vitamin D with regards to a young person. On the other had, elderly people tend to be outdoors less, and for this reason their body has less capacity of producing vitamin D.
Those people who are bedridden or have difficulties for walking, tend to quickly develop a vitamin D deficiency. Additionally, these people usually have less of an appetite and therefore eat less food products that contain vitamin D, thus it is advisable for them to take a supplement.
People who are sick or ill have an increased difficulty to obtain vitamin D through their diet or exposure to the rays of the sun. They spend most of the time inside because of their disease, lack of motivation, and in the worst cases, depression. Therefore sunbathing is not an activity that they carry out, and they inevitably develop a shortage of vitamin D.
People with dark skin or black race have more melanin. This pigment is the cause of the sun rays not being able to penetrate so much the dermis, thus the vitamin D production reduces considerably.
For this reason, people with dark skin have to be in the sunlight for longer than those with light skin, to obtain the same amount of Vitamin D.
When people with dark skin live in latitudes of the north, with time they can develop a vitamin D deficiency. If additionally they can not consume dairy products, due to a congenital lactose intolerance, the supply of this vitamin through the diet is reduced to a larger extent.
Do you have one or various of these symptoms during a period of time longer than three months? In this case, it is possible that you suffer from a shortage of vitamin D, from a mild to severe degree.
As, in general, it is not possible to change our lifestyle or to live in an area where there is sun all year round, taking a Vitamin D dietary supplement is the best option for your vitamin D levels to be optimum and for them to contribute to your health during the whole year.
- Those who live north of the 42nd parallel
- Those residing in large cities, at all latitudes
- Those who always use sunscreen (with a protection factor of 8 or higher)
- Those who spend a lot of time indoors (those who work indoors, the chronically ill, physically disabled, prisoners)
- Night shift workers
- Vegetarians and vegans
- Those who are overweight
- People with dark skin
- People who take certain medications
- Children under 1 year old born in autumn-winter
- Pregnant women
Conclusion: The further away you live from the equator, the darker your skin is, the more overweight you are and/or the less you are exposed to the sun, the more vitamin D you should take. Whether it is taken through diet or as a dietary supplement, to be able to obtain healthy blood levels of this vitamin.
The symptoms that suggest a vitamin D shortage in blood are very varied and the longer that they are prolonged in time, the more severe the vitamin D shortage will be.
The first symptoms are:
- Fatigue and tiredness
- Pessimism and depressed mood
- Slight excitability
- Cravings for sweet food
- Muscular weakness
- Caries and gingivitis
The following symptoms that can take place are reversible with the right intake of Vitamin D:
- Rickets in children
- Osteomalacia (softening of bones)
- Osteoporosis (brittle bones)
- Skeleton-muscle pain
- Susceptibility to allergies
- Infections of the respiratory tract
- Organic pain
If the shortage of vitamin D in blood continues, it may cause the following symptoms, which can be relieved with the adequate treatment:
- Autoimmune diseases
- Rheumatism and degenerative disorders
- Personality changes
- Bone fractures
- Intolerance reactions to food and objects of daily life
- Faults in physical functioning
Recent studies suggest that a vitamin D deficiency in blood is associated to the development of:
- Cardiovascular diseases
- Muscular weakness
- Premenstrual syndrome
- Back and bone pain
- Type I Diabetes
- Multiple sclerosis
- Rheumatoid arthritis
- Among others
This does not mean that these illnesses are caused exclusively by a vitamin D deficiency, but researchers believe that a shortage of vitamin D is a decisive factor that will contribute to its development, and that an adequate intake of vitamin D can reduce the risk of suffering these pathologies.
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