Worldwide, about a billion people suffer from a vitamin D deficiency. But researchers have devised an inventive way to give the tomato a real vitamin boost and thus make it even healthier.

Getting enough vitamin D is very important. For example, it plays an important role in maintaining strong bones, teeth and muscles and a good immune system. Yet many people suffer from a deficiency. For example, approximately one billion people worldwide are deficient in vitamin D, which puts them at greater risk of developing certain diseases, such as cancer, Parkinson’s disease and dementia. In addition, studies have shown that vitamin D deficiency is linked to a more severe form of COVID-19. Researchers therefore decided to look for ways to eliminate this shortage. And perhaps a genetically modified tomato will offer a solution.

Vitamin D

The sun is an important source of vitamin D. When our body catches the sun’s rays, it makes its own vitamin D. But in winter and at higher latitudes, the sun is not strong enough and the human body is unable to produce vitamin D naturally. And then people have to get it mainly from food or supplements. They are then mainly dependent on fatty fish, meat and eggs. However, this is also where the problem lies. More and more people are trying to follow a vegetarian or even vegan diet. And in addition to the foods mentioned, very few foods actually contain enough vitamin D. It means that a vitamin D deficiency is quickly lurking.

Recommended daily amount
It is recommended to get about 10 micrograms of vitamin D daily. For people over 70, an advice of 20 micrograms per day applies. Because the sun is an important source of vitamin D, it is advisable in spring, summer and autumn to sunbathe every day for 15 minutes to half an hour between 11 a.m. and 3 p.m. with at least your head and hands uncovered in the sun. to sit. When a larger part of the body is exposed, a shorter time is sufficient.

Vitamin D occurs in our diet in two different forms, namely ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3). “Currently, all vitamin D3 food sources come from animals,” researcher Cathie Martin told† “You can get vitamin D2 from mushrooms, but it’s not as effective as vitamin D3. Foods rich in vitamin D3 are therefore not suitable for vegans or vegetarians. They are therefore dependent on food supplements prepared from algae or vegan lichens. However, these are much more expensive than regular D3 supplements.”


The researchers therefore decided to look for ways to cope with the vitamin D deficiency. And they took refuge in the… tomato. In the new study Martin and her colleagues tinkered with the genome of this fruit to ensure that it contains more vitamin D. Why the tomato? Tomatoes already naturally contain one of the building blocks of vitamin D3, namely provitamin D3. However, provitamin D3 does not normally accumulate in ripe tomato fruits. “That’s because tomatoes have an enzyme that converts provitamin D3 into cholesterol,” explains Martin. “However, this means that we can switch off this activity without affecting other processes that affect the growth and development of tomato plants. Moreover, we chose the tomato because it is the most eaten vegetable in the world and it is very healthy; it contains, among other things, fiber and important vitamins. And, not unimportant, tomato is delicious!”


To delve a little deeper into the technique, the researchers edited a gene that is involved in the conversion of provitamin D3 into cholesterol. In doing so, the action of the determinant enzyme was blocked. “Using gene editing, we removed a DNA sequence in the gene that codes for the enzyme,” explains Martin when asked. “This prevented an active enzyme from being produced.” The result is the accumulation of vitamin D3 in the fruits and leaves of the tomato plant, without affecting the growth, development or yield of the plant. And after exposure to UV or sunlight, it can then be effectively converted into the highly coveted vitamin D.


The researchers state that the vitamin D you can get from their genetically modified tomatoes is equivalent to eating two medium-sized eggs or 28 grams of tuna. And that’s decent. “It’s more than we expected,” says Martin. “Currently, no vegetables contain enough vitamin D3. This is because plants naturally only produce very low concentrations.” But the genetically modified tomatoes could very well help us to get the daily amount offered.


By the way, you don’t have to worry that these processed tomatoes differ significantly from their normal counterparts. “The manipulated lines look exactly like their parents,” Martin says. “They differ only by the addition or loss of a small number of base pairs in the specific target gene. In short, they look and taste exactly like normal tomatoes.”

Acceptable Resources

So if you are unable to sit in the sun enough or eat foods that contain vitamin D3, genetically modified tomatoes may offer a solution. “Our tomatoes are vegan-friendly sources of vitamin D3,” concludes Martin. “In addition, the leaves – which are currently a waste product – are also rich in provitamin D3 and could therefore be used for the production of vitamin D3 supplements.”

It means that genetically modified tomatoes may even have the potential to make short work of the global vitamin D deficiency and be a solution for millions of people worldwide. And it is not only the tomato that can be effectively tinkered with. The researchers state that other vegetables can also get a vitamin boost. “We may be able to achieve similar changes in close relatives,” Martin says. “Think of potatoes, eggplant and peppers.”