Vitamin D is a fat soluble vitamin that works like a hormone. It’s CRUCIAL to our bodies. Literally every single cell has a receptor for Vitamin D. Every. Single. Cell. Vitamin D is so crucial to our survival that our bodies have developed a way to synthesize it themselves—through the sun.
In order to synthesize it our bodies need plenty of cholesterol. Dietary cholesterol comes from saturated fats from animal foods, the rest your body makes itself.
Foods that are high in vitamin D are:
cod liver oil [be careful with this one, most are highly oxidized before they reach the consumer]
pastured organic egg yolks
caviar
cheese
livers
lard
butter
salmon
sardines and herring
tuna fish
wild mushrooms [not technically plants, they’re a class all their own]
raw milk and raw cream
These same foods are great sources of saturated fat and dietary cholesterol. Vitamin absorption is largely determined by the cholesterol and saturated fats you get from your diet. If you’re not eating cholesterol rich foods you’re most likely not absorbing your vitamins. Anyone who tells you that you can get adequate vitamin D from plants sources is full of it. Fortified foods are NOT the same as whole foods that are full of naturally occurring nutrients. Your body always do it’s best work with the tools you give it, but it’s your responsibility to feed it foods that it can interpret into nourishment.
Our bodies are survivalists. They will do everything they can to scrape the nutrients out of anything you put in them, or to simply detox from whatever you’re putting in them. If all of it’s energy is focused on detoxing from the junk you dump into it then it will have less energy to use the real stuff you give it, and it will be bogged down by spending extra energy on detoxing and last minute protections.
An example of this with regards to vitamin D is that in the absence of vitamin D, 10-15% of dietary calcium and 60% of phosphorous is able to be absorbed; with vitamin D this absorption increases to 30-40% for calcium and 80% for phosphorous.
Outside of calcium metabolism [calcium being the most abundant nutrient in your body, so very important function!], vitamin D stimulates insulin production, prevents IBS, affects myocardial contractility, modulates the function of activated T and B lymphocytes, helps in the treatment of psoriasis [topically & in vivo], aides in wound healing, energy levels, mood heightening, and to prevent hair loss. Vitamin D also promotes calcium reabsorption in the kidneys [a good thing].
What could possibly go wrong?
Vitamin D deficiencies, however, wreak all kinds of havoc in the body. In children it causes rickets, and prevents them from reaching peak bone mass and genetically determined height. In adults, it results in abnormal mineralization of the collagen matrix in bone, which creates weak bones and increased risk of fractures, or osteomalacia—soft bones. This can be quite painful to experience—many report aching bones and muscle pain. So now your body is dealing with a whack-a-mole of new issues stemming from not having the proper tools to adapt and grow. It’s like sending soldiers into a Civil War era battle but letting them know that you don’t actually have any weapons for them to use, so they’ll just have to use their bare hands, and uniforms didn’t come in so they’ll have to go without armor, and maybe even without winter coats— but good luck, fight well!!
Another side of the issue that comes up when Western Medicine leaning practitioners try to correct this deficiency is vitamin D toxicity. This is can be much louder than the deficiency because it also involves an immune system reaction, since it is a foreign, usually synthetic version of vitamin D2 and not what I, and your body would consider ‘real’ vitamin D, which is D3. The most pressing problems from vitamin D intoxication come up when things in our bodies start to calcify. Hypercalcemia leads to symptoms of nausea, vomiting, muscle weakness, kidney stones, constipation, polydipsia [extreme thirst], polyuria [excessive urination], confusion, brain fog, sluggishness, loss of appetite, and neuropsychiatric disturbances. This type of hyper calcification in the body is also linked to a future diagnoses of Alzheimer’s, which *coincidentally* is becoming dramatically more prevalent every year.
Can’t I just get vitamin D from the sun?
It is true that your skin is able to synthesize vitamin D through the use of UVB rays from the sun. However, melanin in the skin also absorbs UVB radiation which then prevents the necessary conversion of 7-dehydrocholesterol to vitamin D. This is why people with increased pigmentation [melanin] need more time in the sun to synthesize the same amount of vitamin D as people with fairer skin. Beyond that, sunscreen is designed to ‘protect us’ from UVB rays which drastically reduces and almost eliminates our cutaneous production of vitamin D. An SPF of 8 reduces cutaneous production of UVB by 95% and SPF 15 will reduce this more than 98%.
In addition vitamin D toxicity from the sun doesn’t happen because our skin destroys excess vitamin D. It only happens from supplementation of vitamin D2 [irradiated wheat], or less often from supplementation of vitamin D3 [the natural bioactive animal derived form] without the proper ratios of vitamin A and vitamin K2. It does not happen from eating whole foods with high levels of vitamin D, especially since vitamin A protects us from vitamin D toxicity, and guess what—they’re both found only in animal products, and usually in the same ones!
So in perfect conditions— i.e. no sunscreen, spring/summer/autumn sun, fairer skin, or long sun exposure with darker skin— at the high end you are only able to synthesize up to 50% of your vitamin D from sun exposure.
So the answer is: Yes and No. You can get a good amount of vitamin D from the sun, and a really bioavailable form of it! [D3] But only when you have been eating adequate saturated, protective, cholesterol rich fats from animal sources, and only when you are getting your sun exposure as often as possible [optimal:daily], without sunscreen and without a buildup of industrial seed oils [which are a HUGE contributor to skin cancers, as well as chemical sunscreens, due to high oxidation and many other factors].
Why is it important to get Vitamin D from my diet?
Since most of us don’t prioritize our daily sun exposure like we need to we are getting drastically less than this while we have also cut out nearly every vitamin D rich food in our diet. Luckily, it’s equally easy and beneficial for all humans to get vitamin D from their whole food sources, even in today’s world. Eat the yolks! And the fat, and the organs, and the bones, and the connective tissues!
In the U.S. it is estimated that 50% of children ages 1-5, and 70% of children ages 6-11 are vitamin D deficient. Those are serious numbers that directly affect your child's health, growth patterns, and gene expression. Of the adult population one review found that 41% of all adults in the U.S. are deficient in vitamin D, as well as 69% of Hispanic adults, and 82% of African American adults. Those numbers are staggering.
An American biochemist began irradiating yeast and other plant foods in 1923 and found that it produced a type of vitamin D. It was labelled vitamin D2. This is what we use to fortify the food-like substances found in our grocery stores, as well as being the form found in nearly all supplements. This is not the same thing as vitamin D3, the bioactive form found in animal products. Most textbooks will hide this truth.
When dealing in the world of nutrition you have to be ever aware of the money trails. Follow the money, and use your critical thinking and evaluation skills to decide whether Monsanto, Procter & Gamble, Johnson & Johnson and other big names who pay for most of the misleading research out there really have YOUR best interest at heart or THEIR OWN BOTTOM LINE. Then decide if you want to take their hired word for it, or if you would prefer more unbiased sources of information. And that’s the case, you are responsible for seeking this information out.
With that in ming, the fact remains that vitamin D2 is an inferior form of this nutrient that is not as effective, nor is it as bioavailable as D3, and is much more likely to result in vitamin D toxicity, but it’s cheaper, and easier to produce than D3, so. :) It does raise serum levels of vitamin D in the body, but it does not perform all of the functions that D3 does. You will be able to find research that suggests it’s helpful in some cases, to me it’s like picking a beyond burger over a steak for ‘health reasons.’
The ins and outs of supplementing Vitamin D:
I believe that vitamin D should not be supplemented, except in extreme cases. You are perfectly capable of getting more than you need by getting outside every day, especially in the spring and summer. Naked is ideal, don’t wear sunscreen, and listen to your skin. When it starts to pink up or feel too hot, dip in water to cool off quickly—this will slow down your ‘burn time’ and allow your skin another chance to synthesize without burning. Then lay out to dry. If it feels hot, itchy, dry or uncomfortable rub your skin with a tallow based lotion and take a break. Start with 5-10 minutes on each side in the winter, and graduate up to however long you want. My sweet spot is 3 hours in peak summer after acclimating my skin, people with darker skin than me can tolerate up to 6 or more hours without adverse effects.
I am NOT advocating for you to get sunburned!! It is YOUR responsibility to learn how to read your skin and know when you need to take yourself out of the sun. I can’t tell you that. It’s different for everyone, and it’s different everyday. Yesterday I spent almost 2 hours in the sun, today only 10 minutes. Tomorrow I will go back up to 2-3 hours. And repeat until winter.
I also have a steady stream of red meat, fat, bones, and organs in my diet. I rotate through different types of eggs, duck, chicken, quail for eggs and I stop eating them in the winter when birds would not be naturally laying. I also eat these fowl as meat, and use their bones for broth. I only cook with tallow, suet, lard, and butter, and I use olive oil and coconut oil sparingly as salad dressings, energy bars, or dessert additions, and only from sources or brands that I trust. Even when I ‘trust’ a brand I still read the labels, because companies are notorious for switching ingredients to cheaper ‘substitutes’ when no ones is looking. I’ve never supplemented vitamin D, nor needed to, even when living in winter climates.
There’s no simple answers here if you’re refusing to work with nature’s intelligence. Nature has provided us the most nutrient dense building blocks in the universe in the form of animal foods of all ilk. The more variety of animals the better for you and for the planet, the sooner you accept that the sooner you will realize what real health feels like.
The best way to find out where your vitamin D stands is to get a blood test one at the end of winter and one at the beginning. There is no need to test more frequently because it takes time to build up. Beyond that there are subtle signs from your body that you’re living in a state of lack. Those are below.
Things to look out for:
1. If you get sick or get infections easily or often— especially with respiratory infections.
2. Tiredness and Fatigue.
3. Bone, back and muscle pain—especially lower back pain, arthritis.
4. Depression, even Seasonal Affective Disorder.
5. Wounds that don’t heal as well, or struggle to heal.
6. Bone loss.
7. Hair loss—especially in women.
7. Hypercalcemia
Resources for personal reading:
https://www.ncbi.nlm.nih.gov/books/NBK441912/
Nourishing Fats by Sally Fallon Morrell
Eat the Yolks by Liz Wolfe
The Big Fat Surprise by Nina Teicholz
These next two are just for quick reference lists. Healthline isn’t a completely trustworthy source of information, it’s important to check their sources. They are still largely hooked on government recommendations for diet which are consistently some of the most heinous recommendations I’ve ever seen. So take these with a scoop of salt.
https://www.healthline.com/nutrition/9-foods-high-in-vitamin-d#The-bottom-line
https://www.healthline.com/nutrition/vitamin-d-deficiency-symptoms#12