Vitamin D plays a major role in keeping us healthy by helping to regulate the metabolism of most of our body tissues. While this nutrient is sometimes referred to as the sunshine vitamin, even people living in the sunniest states in our country suffer from a lack of it. So, how is this possible?
Various factors predispose us to lack vitamin D. In our new article, we will delve into this increasingly common problem and share with you the best recommendations for avoiding hypovitaminosis D. Are you ready to learn everything there is to know about the sunshine vitamin?
- 1 Weekly newsletter with the best personal finance tips
- 2 Key Facts
- 3 Our Selection: The Best Products to Prevent Vitamin D Deficiency
- 4 Everything You Should Know About Vitamin D Deficiency
- 5 Buyer's Guide
- 6 Summary
- Vitamin D deficiency may affect up to 50% of the world's population, negatively impacting bone, metabolic, and cardiovascular health.
- A poor diet and low exposure to sunlight are the primary responsible for vitamin D deficiency.
- Various options are available to you if you decide to treat this condition with supplements. These include multivitamin preparations, fish oil, and vitamin D products.
Our Selection: The Best Products to Prevent Vitamin D Deficiency
If you plan on taking supplements to combat this condition, you will find the following section helpful. We have selected the most popular and effective products currently available on the market. We strongly encourage you to follow the manufacturer's recommendations. If you want to use higher doses, please do so under the supervision of a health professional.
Everything You Should Know About Vitamin D Deficiency
Vitamin D deficiency has become a real issue around the world. Experts point to an increasingly sedentary lifestyle, where work and leisure occur indoors, as the main culprit for this. But is the solution really to get more sun, risking the consequences of excessive exposure? Let's delve into this seeming dilemma!
The Sunshine Vitamin
|Regulatory function||Clinical benefits*|
|Bones: It increases calcium absorption at the intestinal level and allows the mineralization of bone.||Decreased risk of fractures.|
|Muscles: It promotes muscle contraction.||Reduced risk of falls, which consequently reduces the risk of fractures in the elderly.|
|Cardiovascular: It contributes to arterial relaxation.||Possible reduction of blood pressure, decreased risk of cardiovascular events.|
|Reproductive: Formation of estrogen-type hormones and testosterone.||Lower incidence of bacterial vaginosis and pelvic floor failure.|
|Immune: Regulation of immunity.||Lower frequency of autoimmune diseases (type multiple sclerosis), reduced probability of infection by the influenza A virus.|
|Nervous: Possible neuronal protection (currently under study).||It may reduce the frequency of degenerative diseases (Parkinson's, macular degeneration), depression, and dementia.|
|Endocrine: Modulation of insulin-type hormone production. Appetite regulator.||It may promote better control of blood sugar levels and body weight.|
|Others: Control of cell replication.||It may decrease the risk of certain types of tumors (especially colon and rectal).|
*Comparison with insufficient vitamin D levels.
As you can see, maintaining healthy vitamin D levels in your blood (between 30 and 75 nanograms per milliliter in adults) is essential to keeping your body healthy (1). However, there is a lack of this nutrient in nature, with few foods containing it compared to other vitamins (such as C or B vitamins).
To overcome this difficulty, the human body has created an effective system that allows it to synthesize vitamin D from cholesterol derivatives. This chemical reaction only requires the exposure of the skin to sunlight. This is why some people call it the sunshine vitamin (2).
Recommendations & At-Risk Groups
|Population group||RDA (International Units, IU)|
|Babies, 0-6 months||400|
|Babies, 6-12 months||400|
|Children, 1-3 years||600|
|Children, 4-8 years||600|
|Teenagers, 9- 18||600|
|Adults, up to 70 years||600|
|Adults, over 70 years||800|
Meeting these recommendations is particularly important for the groups most at risk of suffering from a deficiency. Children, teenagers, pregnant or breastfeeding women, and people over the age of 65 are considered high-risk groups when assessing the potential lack of vitamin D.
In addition, anyone who decides to cover most of their body and not expose it to sunlight should closely monitor their vitamin D levels. The same goes for people living in regions with few hours of light per day or with cloudy skies (4).
D for Diet: Prevention Through Food
Vitamin D3: Cholecalciferol is mainly found in animal products (dairy products, eggs, oily fish, and entrails). However, some lichens are also capable of producing small quantities of vitamin D3. The absorption of this type of vitamin D is superior to that of ergocalciferol, although the foods that contain it are very rich in fat and calories (25, 26).
|Food (100 grams or 100 milliliters)||Approximate concentration (IU)||Calories|
|Cod liver oil||10,000||900|
|Fortified skimmed milk||332||362|
Vitamin D2: Ergocalciferol is a variant of vitamin D that plants, fungi, and certain bacteria synthesize after being exposed to solar radiation. Unfortunately, this vegan alternative has proven to be less efficient than cholecalciferol in raising blood concentrations of vitamin D (26).
|Food (100 grams or 100 milliliters)||Approximate concentration (IU)||Calories|
|Fortified orange juice||60||44|
|Soybean milk fortified with D2||50||33|
|Fortified rice drink||40||47|
If you are vegan or cannot increase your intake of vitamin D3-rich foods due to their high calorific content, you will have to combine a quality diet and sun exposure to avoid hypovitaminosis. Otherwise, you can turn to vitamin D supplements as a last resort (18).
|It cannot produce intoxication or overdose.||Foods rich in vitamin D3 are very caloric.|
|Foods with vitamin D provide other benefits (omega-3, antioxidants, selenium, or vitamin E).||The bioavailability of vitamin D2 is reduced.|
|Infant foods are often fortified with vitamin D (prevention of rickets).||There is a limited number of foods rich in vitamin D2. Non-fortified vegan options are few and far between.|
|This type of diet can be challenging for individuals allergic to fish, milk, or soy.|
|Elderly or chronically ill people (e.g. Crohn's) have a lower absorption capacity.|
Taking Back Control: Supplements for Vitamin D Deficiency
These products come in different formats and doses. You can find them as capsules, but also drops and sprays that are ideal if you aren't comfortable swallowing tablets. While injectable megadoses of vitamin D exist, they are exclusively used by health professionals.
If you follow a vegan diet, keep in mind that your body's ability to absorb vitamin D2 supplements is inferior to cholecalciferol products. In that regard, you may want to ask your physician to adjust the dosage accordingly. Vegan D3 (from lichen) is currently used to develop supplements (27).
The use of these supplements is simple. If you plan on using them for a limited time and without medical supervision, follow the manufacturer's instructions and recommended doses (800-1,000 IU of vitamin D3 per day). Weekly and monthly preparations may cause side effects, so their consumption needs to be under the supervision of a doctor or a nutritionist (16, 28, 29).
|Supplements are very effective in raising vitamin D blood levels.||They can potentially be toxic at high concentrations (300,000 IU or more).|
|Supplementation allows you to adjust your intake.||Used unsupervised and at high doses, they can increase blood calcium. Paradoxically, this could increase the risk of fractures.|
|They come in different dosage forms (capsules, liquid, and spray).||There have been reports of drug interactions.|
|You can find vegan and vegetarian options.||Vitamin D3 is mostly of animal origin (wool and fish).|
Supplementing With Caution
Excess vitamin D in the blood can be as harmful as a lack of it. In fact, a higher incidence of falls and fractures has been found in people who consumed large doses of cholecalciferol (10,000 IU per day for years). This is why you should limit your consumption of vitamin D supplements to a maximum of 4,000 IU per day (29).
In addition, we recommend that you discuss with a health professional if you want to supplement for a period longer than three months. People with specificities (obesity, intestinal malabsorption, or diagnosed osteoporosis, among others) may need doses higher than 1,000-2,000 IU/day and should also consult a specialist.
Children under the age of 18, as well as pregnant and breastfeeding women, should supplement under strict clinical supervision. This also goes for anyone with a chronic disease (heart, liver, or kidney) and to individuals following the drug therapies listed in this table (31):
|Duodenal ulcer treatment||Cimetidine|
If you are determined to use supplements to keep vitamin D deficiency at bay, you will find the following section very helpful. We will delve into the main characteristics of vitamin D supplements; that way, you can pick those that best fit your needs.
Vitamin D Supplements
Products that exclusively consist of vitamin D (cholecalciferol or ergocalciferol) are the most widely used supplement to prevent or treat vitamin D deficiency. If you follow a vegan diet, remember to use a D2-based product and consult a nutritionist to adjust the dosage.
- Daily use: Everyday supplements should contain moderate amounts of vitamin D (800-2,000 IU), never exceeding 4,000 IU/day. Taking them with food will increase absorption.
- Weekly use: You can also find products with high doses of vitamin D (4,000-10,000 IU). While they are effective in raising blood levels, they have an increased risk of side effects (hypercalcemia). Do not take them without consulting a health professional beforehand.
- Monthly use: Megadoses (100,000-300,000 IU) of vitamin D are used in strict medical settings to treat severe and symptomatic deficiencies. Administered via injections once a month, this must be medically supervised (29).
The cost of these vitamin D supplements will depend on the format, dose, raw material (lichen, sheep's wool fat or fish oil), and brand reputation. The number of capsules or tablets will also influence the price.
Multivitamins With Vitamin D
These supplements are a great way to combine vitamin intake. However, they often contain less vitamin D than other products (50 or 75% of the RDA). If you opt for multivitamin supplements, it should complement a diet rich in D3 or D2 and careful exposure to the sun.
Fish Oil Supplements
The most traditional remedy to prevent vitamin D deficiency is cod liver oil. In the past, it was marketed in liquid extracts, and the taste horrified children. Today, you can find it in capsule form or with flavoring. Cod liver oil is rich in vitamins D3, E, A, and omega-3 fatty acids (EPA and DHA) (32). It can prevent and treat various nutritional deficiencies effectively and economically. Here are some of its benefits (33):
|Vitamin A||Antioxidant. Bone and tooth maintenance. Preservation of the retina's function.|
|Vitamin E||Antioxidant. Maintenance of the function of the immune system. It may prevent premature skin aging.|
|Eicosapentaenoic acid (EPA)||Omega-3 fatty acid. Improvement of the lipid profile. Possible anti-inflammatory properties.|
|Docosahexaenoic acid (DHA)||Omega-3 fatty acid. Possible anti-inflammatory properties. Preservation of normal intellectual function.|
Vitamin D deficiency has been associated with an increased incidence of osteoporotic fractures and growth alterations in children. This condition could also negatively affect mental and cardiovascular health. In fact, the most alarming data even link this nutritional deficiency to the appearance of tumors of the colon and rectum.
In an increasingly sedentary world, where most of us live confined in our homes and workplaces, hypovitaminosis D has become a public health problem. However, a healthy diet, cautious sunbathing, and smart supplementation will keep this issue at bay!
Do you feel more comfortable dealing with vitamin D deficiency after reading our guide? We'd love to hear your opinion, so please leave us a comment in the section below. You can also share this article on your social media!
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