Eggs have long been touted for being rich in vitamin D, a key nutrient for bones and the immune system. However, a habit that many consider harmless could actually reduce their intake. According to a study by the University of Newcastle, keeping eggs cold would alter the content of vitamin D3, the most active form of this vitamin. A detail that is not one, especially in winter, the period when deficiencies are most frequent.
Should you store your eggs in the refrigerator or at room temperature?
The debate has agitated egg lovers for years. But this time, science provides a clear answer. After comparing eggs kept in the fridge and others left at room temperature, the researchers observed a significant difference. “We’ve found that if you want to retain more vitamin D, it’s best to keep eggs out of the refrigerator, at room temperature.” says Tom Hill, professor of nutrition and lead author of the study.
The cold actually alters the structure of certain vitamins, including D3, which reduces their bioavailability. Result: even a food naturally rich in vitamin D can lose part of its benefits simply because of poor storage.
What cooking method best preserves the vitamin D in eggs?
The researchers also looked at cooking, another determining factor. Their ranking is unequivocal:
- Scrambled eggs: 109% retention;
- Microwave eggs: 109%;
- Poached eggs: 93%;
- Hard-boiled eggs: 80%;
- Fried eggs: 78%.
Scrambled eggs and those cooked in the microwave are therefore the champions of vitamin D. Conversely, prolonged cooking of hard-boiled or fried eggs promotes a breakdown of the fat-soluble compounds responsible for this vitamin.
Why do these gestures make all the difference?
A large part of the population has a vitamin D deficiency, accentuated by lack of sun exposure. As Tom Hill recalls: “We now know that beyond the chickens’ diet, the way you cook eggs influences the amount of vitamin D you will consume“.
In short, to fully benefit from the benefits of eggs, it is better to keep them at room temperature and favor scrambled or microwaved eggs. A simple little gesture, but with a strong nutritional impact.