The importance of vitamin D for the human body, together with how widespread its deficiency is, motivates most of us to take it as a dietary supplement. The range on the market is very wide, and although it might seem that vitamin D products hardly differ from one another, the opposite is true. The differences come mainly from the type of vitamin D (the best known are D2, ergocalciferol, and D3, cholecalciferol), the raw materials used in production and the technological process used to make it.
Our aim is to outline the basic differences between the individual sources (and therefore products) and make it easier to decide between vitamin D of animal or plant origin. We have gathered the latest information about this molecule and the sources used to produce it, and summarised it clearly in this article.
What you will learn in this article:
- First, a little about vitamin D
- Can vitamin D be obtained naturally?
- Widespread vitamin D deficiency is alarming
- It pays to choose truly high-quality sources
- Animal-origin vitamin D supplements
- A brief look at how vitamin D is made from lanolin
- An animal source is not just a question of ethics, but also of chemicals
- Plant sources: sustainability and respect for nature
- Lichen: a breakthrough plant source of vitamin D3
- What are the main benefits of vitamin D from lichen?
First, a Little About Vitamin D
Vitamin D is a fat-soluble vitamin. In the body, however, it behaves more like a hormone, regulating bone formation and the absorption of calcium and phosphorus from the intestine. It helps control the exchange of calcium between bones and blood. In infancy and childhood, vitamin D deficiency causes bone deformities known as rickets, while in adults it causes softening of the bones, known as osteomalacia. But bone health is far from its only function. Today we know that vitamin D has a much wider role in the human body and is involved in a whole range of physiological processes. According to the authorised EU health claims, vitamin D contributes to the maintenance of normal bones, teeth and muscle function, contributes to the normal function of the immune system and has a role in the process of cell division.
Can Vitamin D Be Obtained Naturally?
The main source of vitamin D is exposing the skin to sunlight. For synthesis to start in the skin cells, however, there must be sufficient exposure to UVB radiation with a wavelength of 280–315 nm. In Central Europe, for example in the Czech Republic, this is available roughly from May to September between 10 a.m. and 4 p.m. During the first days of summer the sun is not as strong and the window is even shorter, roughly 11 a.m. to 3 p.m., and the same applies at the end of summer, around the turn of August and September.
The intensity of UVB radiation reaching the ground is described by the UV index. Regions where the UV index stays above 4 permanently or for most of the year have much better conditions for vitamin D synthesis (in Central Europe, this is only the case on sunny summer days). There are apps that calculate precisely, based on your current location, whether the angle of the sun is sufficient. You can also follow a simple shadow rule: if your shadow is much longer than you are, the sun is not at a sufficient angle and synthesis will not take place. Many other factors also significantly affect how much vitamin D we end up storing. You can read more in our article Sun as a source of vitamin D.
So for many of us who live in cities and work fixed office hours, getting enough vitamin D naturally in summer can feel more like a treasure hunt. In winter, the only sources of vitamin D are oily fish and a few other foods, which are gradually disappearing from our everyday diet. It is no wonder, then, that many people lack vitamin D and have low levels for much of the year.
Widespread Vitamin D Deficiency Is Alarming
Vitamin D is a much-needed substance for our body, so we cannot rely solely on production in the skin, and certainly not on food sources alone. Many researchers even call for raising the minimum recommended daily intake, which the EFSA currently sets at 15 µg/day (600 IU) for adults. In its 2011 guideline, the Endocrine Society recommended higher doses of 1,500–2,000 IU for all men and women over 18, including breastfeeding and pregnant women, especially when a vitamin D deficiency has been confirmed.
It Pays to Choose Truly High-Quality Sources
There is a huge number of products on the market that differ both in the source used to make them and in its quality. Many of them also contain a whole list of ingredients that are hard to decipher, and consuming them over the long term may have an adverse effect on health. It should also be added that manufacturers are not required to list many additives on the label (they are considered part of the production technology). A suspiciously low price, a long shelf life or a striking colour or taste can all indicate additives whose safety profile is debatable. For the average consumer, it is often not easy to find their way through the options. So let us look at the basic sources used to produce vitamin D and how they differ.
Animal-Origin Vitamin D Supplements
A common raw material for producing vitamin D, used for most products on the market, is lanolin. The term comes from the Latin lana (wool) and oleum (oil), although chemically it is classed as a wax. It is a secretion produced by the sebaceous glands of sheep that protects the wool from rain and other adverse environmental influences. Although collecting lanolin from the fleece during shearing does not harm the sheep (if done correctly and gently), it is an animal source, so products made from it are not suitable for people who follow a vegan lifestyle.
A Brief Look at How Vitamin D Is Made from Lanolin
The shorn wool is first washed in hot water with detergent to remove any parasites or impurities, producing crude lanolin. A process called saponification, followed by centrifugation, then separates the fatty component from the non-fatty one. Crude cholesterol is isolated using extraction agents and solvents. After further chemical processing, 7-dehydrocholesterol (provitamin D3) is finally produced. It is chemically identical to the provitamin under our skin that reacts with sunlight to form vitamin D3. In the last step, 7-dehydrocholesterol is exposed to light to create the final stable form of vitamin D3, ready for supplement production.
An Animal Source Is Not Just a Question of Ethics, but Also of Chemicals
Other undesirable substances involved in producing vitamin D from lanolin can include pesticides or preservatives.
Sheep's wool can be contaminated with pesticides it comes into contact with on pastures from chemically treated plants, and the animals and their skin are also dipped in disinfectant baths against ticks and other pests.
Because lanolin is a fat, it can go rancid or oxidise on contact with air. To extend its shelf life, many manufacturers add BHT (butylated hydroxytoluene) to lanolin, the most widely used synthetic antioxidant for slowing the rancidity of oils and fats. Although BHT is considered safe in appropriate amounts, trace amounts remain in human fat tissue, and some animal studies have raised questions about its effects on health.
Plant Sources: Sustainability and Respect for Nature
There is no doubt that the world is moving towards sustainability, and ethics plays a big role in choosing products. If you have decided to follow a plant-based diet, or want to live more sustainably to be kinder to the planet and respect nature and animals, products made from lanolin extract are certainly not the right choice.
For a long time, the non-animal alternative was vitamin D from mushroom extract. Chemically, this form corresponds to vitamin D2 (ergocalciferol), which is now considered a less effective source of vitamin D than D3. A 2011 study published in the Journal of Clinical Endocrinology & Metabolism compared vitamin D2 with vitamin D3 and concluded that vitamin D3 was approximately 87% more potent and maintained serum 25(OH)D concentrations for much longer. [1]
Lichen: A Breakthrough Plant Source of Vitamin D3
Lichens are fascinating organisms formed in nature by a symbiosis of an alga and a fungus. Thanks to this unique partnership, lichens in the wild can naturally synthesise and accumulate high amounts of nutrients, including vitamin D3.
Vitamin D3 extracted from lichen is chemically identical to the vitamin D3 obtained from lanolin or produced in our skin in sunlight.
What Are the Main Benefits of Vitamin D from Lichen?
- Suitable for vegetarians and vegans
- Purity without chemicals: cultivation and processing take place under strictly controlled conditions, in a closed cycle, without pesticides, harsh chemical solvents or synthetic preservatives
- An ecological and sustainable production method that is gentle on nature and animals
- Energy saving (the production process is not energy-intensive)
- Our product contains no chemical preservatives
The only disadvantage of this plant source is its higher price, which is balanced by the unique cultivation process, technological processing and the purity of the product. And last but not least, the ethical aspect plays an important role too.
Sources:
[1] Heaney RP, Recker RR, Grote J, Horst RL, Armas LAG. Vitamin D3 is more potent than vitamin D2 in humans. J Clin Endocrinol Metab. 2011;96(3):E447–E452. doi:10.1210/jc.2010-2230. https://doi.org/10.1210/jc.2010-2230
