Vitamin D: What’s up sunshine?
An open love letter to the sun and how important vitamin D is to your health.
Vitamin D, is the sunshine vitamin that's essential for your health and well-being. I shed some (sun)light on why this nutrient is so crucial and how you can ensure you're getting enough of it.
What is vitamin D?
Why do we need it?
Vitamin D is an essential nutrient for growth, immunity, bones, teeth, brain health, regulating our heart rates and inflammation. How can we get enough? What are its benefits?
What is vitamin D?
Fat-soluble vitamin D has the properties of both a vitamin and a hormone. It’s available in few foods, added to some dietary “staples”, available as a supplement, and we can source it from the sun.
What do you need vitamin D for?
Vitamin D plays a vital role in:
calcium absorption in the gut, which is essential for maintaining strong bones and teeth.
growth
protecting against muscle weakness
regulating your heart rate
supporting immune function
regulating mood
helping to reduce inflammation in the body
getting enough vitamin D has been linked to a lower risk of chronic diseases like heart disease and certain cancers.
Why is it the ‘sunshine vitamin’?
Did you know that your body can produce vitamin D when your skin is exposed to an adequate amount of sunlight? Just a few minutes of sun exposure each day can help boost your vitamin D levels naturally. For those of us living in a more northern climate, this feels impossible when we have winter for 5-6 months of the year. With long winters, we need alternative sources of vitamin D.
Getting enough vitamin D
Are you getting enough? How can you tell? Is there such a thing as vitmin D toxicity?
How much vitamin D do you need?
Getting enough vitamin D from sunlight depends on various factors like your skin tone, the time of day, and your location. Generally, experts recommend spending about 10-30 minutes in the sun without sunscreen three times a week to help your body produce vitamin D. Of course, you'll want to be mindful of sun safety and avoid prolonged exposure, especially during peak hours.
When it comes to dietary sources, here's a breakdown of the recommended daily intake of vitamin D based on age:
What does a deficiency look like?
A deficiency in vitamin D can lead to a range of symptoms, including fatigue, muscle weakness, bone pain, and an increased susceptibility to infections. In severe cases, it can even cause conditions like rickets in children and osteomalacia in adults, which weaken the bones and increase the risk of fractures.
Rickets is the most commonly talked about vitamin D deficiency. This is a disease where the bone tissue doesn’t properly mineralize and soft bones or skeletal deformities occur.
You may be at risk if you fall into one of these groups:
Breastfed infants that are exclusively breastfed and well covered when outside (which is advised)
Older adults, because of the skin’s declining ability to synthesize vitamin D
People in northern climates or with limited sun exposure
People with dark skin, which reduces the skin’s ability to produce vitamin D from sunlight
People with conditions that limit fat absorption (Crohns, celiac, liver disease, cystic fibrosis, ulcerative colitis)
People with obesity or have had gastric bypass surgery
What about vitamin D toxicity?
While vitamin D toxicity is rare, it can occur with excessive supplementation. What tends to happen is calcium will begin to build up in your blood, also known as hypercalcemia. There are other serious problems that can occur, including kidney issues, bone pain and calcium stones.
What are the symptoms?
Symptoms may include confusion, apathy, nausea, vomiting, weakness, and frequent urination. It's essential to stick to recommended dosages to avoid toxicity and consult with a healthcare professional before starting any new supplements.
How much is too much?
Adhering to the guidelines and staying under 4000 IU/day is recommended. In some circumstances, a higher dosage may be recommended. There are many factors that would affect your own personal tolerance level, such as absorption. But dangerously high levels are in excess of 10,000 IU/day.
Absorption in your body. Interaction with other nutrients.
Do we absorb nutrients differently and will other supplements help or hinder our absorption?
What about vitamin D absorption?
The form of vitamin D that we get from supplements or in food is not fully active. We need conversion by the liver, then by the kidneys before it becomes fully active. If you’re struggling with a kidney or liver disorder, you may be at a higher risk for osteoporosis as a result of this conversion element.
What forms of vitamin D are there? Is one easier to absorb?
There are different forms of vitamin D, including ergocalciferol (D2) which comes from food, cholecalciferol (D3) which is synthesized in the skin in response to sun exposure or from animal products, and D5 which is a synthetic form. D2 and D3 are the most common forms.
D3 is generally found in animal products, such as lanolin from the wool of sheep, and it can also be derived from lichen (the vegan form). Whereas D2 is found in mushrooms and manufactured using UV irradiation of ergosterol in yeast. No matter the form or source, D2 and D3 are well absorbed in the small intestine.
Vitamin D absorption can be affected by factors such as:
age
skin colour
geographic location
medical conditions
Limited exposure to sunlight, especially during the winter months, can hinder vitamin D synthesis in the skin. Certain medical conditions like fat malabsorption disorders can also impair the absorption of fat-soluble vitamins like vitamin D.
TIP: When consuming vitamin D, ensure you take it with source of fat to aid in absorption. Some supplements come in fat-ready forms with coconut or MCT oil.
What about vitamin D and its interaction with other nutrients?
Vitamin D promotes calcium absorption in the gut and maintains adequate calcium and phosphate concentrations to enable bone mineralization.
You may have seen supplements with vitamins D and K together - i.e. D3 & K2. Vitamin K, also fat-soluble, is a non-essential nutrient, meaning your body produces enough of it. Together, these two vitamins work together to ensure calcium is properly utilized in the body.
NOTE:
Currently, there is no clear evidence to support the need to supplement with vitamin K.
Common dietary sources of vitamin K are found as phylloquinone in green leafy vegetables like spinach, kale, collard greens, Brussels sprouts, cauliflower and some fruit. Menaquinone is found in some animal foods and fermented foods (natto is a good source) and in our bodies, produced by bacteria.
SAVE YOUR SUPPLEMENT DOLLARS AND GO FOR VITAMIN D ALONE
Where to get your vitamin D? Which supplements are right?
Determining where your vitamin D comes from and which supplement is right are the next steps.
Which vegan foods are fortified with vitamin D?
Vitamin D-fortified foods for vegans include plant-based milk alternatives, breakfast cereals, and orange juice. Additionally, mushrooms exposed to UV light can naturally synthesize vitamin D. However, sunlight remains the primary source of vitamin D for most people.
Which vitamin D supplement is right?
If you live in a part of the world where sunlight is scarce during your winter months, then supplementing might be your best option to ensure you’re getting enough.
Vitamin D3, generally derived from animal sources like lanolin, is more effective at raising blood levels of vitamin D compared to vitamin D2. However, there are vegan-friendly vitamin D3 supplements sourced from lichen available for those following plant-based diets. Always consult with a healthcare professional to determine the right dosage and form of vitamin D supplementation for your individual needs.
Remember, maintaining optimal levels of vitamin D is key to supporting bone health, immune function, and overall well-being. So, make sure to soak up some sun (safely, of course!) and hit the chat button if you’re looking for the best supplements for you to keep those vitamin D levels in check. Stay healthy!
Not an ad or recommendation.
Sources:
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