Vitamin D

Vitamin D is essential for several reasons, including maintaining healthy bones and teeth. Despite its name, vitamin D is not a vitamin, but a prohormone, or precursor of a hormone.

Vitamins are nutrients that the body cannot create, and so a person must consume them in their diet. However, the body can produce vitamin D, it does so as a response to sun exposure. A person can also boost their vitamin D intake through certain foods or supplements.

Vitamin D has multiple roles in the body. It assists in:

• Promoting healthy bones and teeth
• Supporting immune, brain, and nervous system health
• Regulating insulin levels and supporting diabetes management
• Supporting lung function and cardiovascular health
• Influencing the expression of genes involved in cancer development
• Reduced risk of cold and flu

Some studies even go as far as saying there is no such thing as cold and flu season, only a vitamin D deficient season. This is where we lack enough quality sunlight due to shorter days and poor weather conditions.

What happens when we run low?

Although the body can create vitamin D, a deficiency can occur for many reasons.

Skin type: Darker skin, for example, and sunscreen, reduce the body’s ability to absorb the ultraviolet radiation B (UVB) rays from the sun. Absorbing sunlight is essential for the skin to produce vitamin D.

Sunscreen: A sunscreen with a sun protection factor (SPF) of 30 can reduce the body’s ability to synthesize the vitamin by 95% or more 

Covering the skin with clothing can inhibit vitamin D production also.

Geographical location: People who live in northern latitudes or areas of high pollution, work night shifts, or are homebound should aim to consume vitamin D from food sources whenever possible.

Fatigue & Tiredness: Vitamin D deficiency has been linked to feelings of fatigue, tiredness and even impacting the quality of sleep. Other studies have also linked it to depression with some knowing the symptoms as ‘SAD’ disorder (seasonal affective disorder)

Common symptoms

Common symptoms of vitamin D deficiency may include:

• Regular sickness or infection
• Fatigue
• Bone and back pain
• Low mood
• Impaired wound healing
• Hair loss
• Muscle pain

If Vitamin D deficiency continues for long periods, it may result in complications such as:

• Cardiovascular conditions
• Autoimmune problems
• Neurological diseases
• Infections
• Pregnancy complications
• Certain cancers, especially breast, prostate, and colon.

So how much do we need?

The recommended daily intakes of vitamin D are as follows:

• Infants 0–12 months: 400 IU (10 mcg).
• Children 1–18 years: 600 IU (15 mcg).
• Adults up to 70 years: 600 IU (15 mcg).
• Adults over 70 years: 800 IU (20 mcg).
• Pregnant or lactating women: 600 IU (15 mcg).

Sensible sun exposure on bare skin for 5–10 minutes, 3–4 times per week, allows most people to produce sufficient vitamin D. However, vitamin D breaks down quite quickly, meaning that stores can run low, especially in winter.

It would then be to your benefit to increase your intake through supplementation or increased sunlight exposure. (of course, taking care to protect your skin from strong UV light) 

How much is too much?

The upper limit that healthcare professionals recommend for vitamin D is 4,000 IU per day for an adult. However, the National Institutes of Health (NIH) say that vitamin D toxicity is unlikely at intakes under 10,000 IU per day.

Excessive consumption of vitamin D can lead to over calcification of bones and the hardening of blood vessels, kidney, lung, and heart tissues.

The most common symptoms of excessive vitamin D include headache and nausea. However, too much vitamin D can also lead to the following:

• Loss of appetite
• Dry mouth
• A metallic taste
• Vomiting
• Constipation
• Diarrhoea 

Excess vitamin D usually occurs from taking too many supplements. It is best to get vitamin D from natural sources.

Where can we find it?

Getting sufficient sunlight is the best way to help the body produce enough but we can also gain vitamin D from food… below are some simple sources you can add to your daily intake. (Quantities may vary depending on your individual calorie requirements)

• fatty fish, such as salmon, mackerel, and tuna
• egg yolks
• cheese
• beef liver
• mushrooms
• fortified milk
• fortified cereals and juices
  

What do our coaches suggest you do?

Make a conscious effort to get outdoors and gain natural light on your skin in the earlier hours of the day, this will also help keep your circadian rhythm in check too!

Incorporate fatty fish in your diet 2-3 times per week and seek out a high-quality vitamin D supplement if you struggle to get outdoors especially during the winter months.

For more information such as this then please head to our blogs to have a full overview of all things health and fitness.

Share: