In cold winter weather, many people turn to insulated cups to keep their tea or other beverages warm while enjoying a dose of healthiness.

The primary function of these cups is to maintain the heat of the drink, and they come in various brands.

In conducting an experiment with various brands of insulated cups, pouring water, tea, and milk into them and leaving them untouched for three days, a surprising discovery was made.

Some of these cups displayed varying degrees of corrosion on their inner walls.

Upon closer inspection, we found an excessive presence of heavy metals, such as chromium and manganese, in the liquid stored in these cups.

Therefore, it is crucial for individuals who prefer using insulated cups for their beverages to invest in high-quality and reputable products to ensure their safety.

How to choose a reliable insulated cup:

1. Check the Brand: The market is flooded with a plethora of insulated cup options, making it easy to become overwhelmed. To make a confident choice, consider the brand. Trusted and well-known brands are often more reliable, despite the higher price tag. Investing a little more in your health is worth it.

2. Examine the Material: For those not well-versed in the market, determining the quality of the insulated cup's liner can be challenging. It's essential to ensure that the liner is made of "food-grade" stainless steel, which means that it meets strict safety standards regarding harmful substances.

3. Check for Odor and Workmanship: Open the cup's lid and take a whiff. If you detect a pungent odor, likely, that the liner is not made of food-grade stainless steel. Insulated cups with no odor meet national standards. Additionally, inspect the cup's workmanship. If the interface is impeccably crafted and free of defects, it's a sign of a more reliable insulated cup.

How to properly clean an insulated cup:

1. Thorough Cleaning: Cleaning an insulated cup isn't a simple task; it requires attention to detail. You must clean the cup surface, liner, and cap without leaving any area untouched.

2. Salt and Warm Water: Start by adding a small amount of edible salt to the cup and fill it with warm water. Shake the cup to ensure the salt dissolves and covers all surfaces inside. Leave this solution for approximately 10 minutes to effectively kill bacteria.

3. Lid Cleaning: Remove the lid and use a toothbrush with toothpaste to scrub the crevices and all parts of the lid meticulously. Toothpaste has some antibacterial properties, which can help maintain cleanliness.

4. Eggshell Cleaning: Crush some eggshells and place them in the cup. Fill the cup with cool water, seal it with the lid, and hold it securely. Shake the cup in all directions for about 20 seconds. Afterward, remove the lid, discard the eggshells, and rinse the cup thoroughly with water.

5. Final Rinse: Rinse the cup, both inside and outside, with water two to three times to ensure all residues are removed.

6. Drying: After washing, allow the cup and the lid to air dry separately. Avoid immediately covering the lid, and if possible, place them in sunlight to eliminate any odors.