Conclusion
Strawberries for a fact do not lift stains from your teeth. The whitening effect that strawberries give on teeth is temporary and would likely fade off before the day is over.
It is much better and safer to opt for Over-the-counter products for whitening your teeth at home.
The best way to keep your teeth white is to brush them twice daily with a fluoride toothpaste for two minutes and to floss at least once a day. It is best to discuss with your dentist about other alternatives if you are still searching for another option.
Reference:
[1] https://www.healthline.com/nutrition/foods/strawberries
[2] https://www.healthline.com/nutrition/citric-acid
[3] https://www.webmd.com/beauty/ss/slideshow-beauty-baking-soda-health
[4] https://www.ada.org/
[5] https://www.webmd.com/oral-health/guide/dental-health-cavities