Washing machine never wash your laundry at 40°C. That’s the reason!

At 40°C, many common bacteria, viruses, and allergens are not fully eradicated, especially those that can thrive in warmer environments. So, if you’re hoping to remove germs, mold, or bacteria from your laundry, washing at 40°C could leave you at risk of re-contaminating your clothes.

Why 40°C Might Not Kill Germs

1. Temperature Range and Bacteria Growth: Bacteria and viruses, like those from bodily fluids or food stains, require a higher temperature to break down effectively. Washing at 40°C may not generate the necessary heat to kill harmful microorganisms thoroughly. In fact, many viruses and bacteria are more resilient to temperatures around this range.
2. Not Hot Enough for Full Disinfection: While washing clothes at 40°C can remove visible dirt and odors, it often fails to reach the higher heat needed to disinfect items, especially bedding, towels, and underwear. To eliminate germs and allergens, a temperature of 60°C (140°F) or higher is typically recommended. Studies show that washing at 60°C significantly reduces bacterial contamination compared to washing at 40°C.
3. Allergens and Dust Mites: Washing your sheets and towels at 40°C might not be enough to fully eliminate dust mites, pet dander, and other allergens. These tiny creatures thrive in fabrics and are resistant to low temperatures. A hotter wash at 60°C or higher can help remove dust mites and other allergens effectively.

The Impact on Your Laundry and Washing Machine

While washing at 40°C may seem like a gentler option, it can also have a few unintended effects on your laundry and the washing machine:

• Stains Set In: At lower temperatures, certain stains, especially grease-based ones, may not break down as effectively. This can lead to stains being set into fabrics, making them harder to remove later.
• Detergent Performance: Many detergents are formulated to work best at higher temperatures. At 40°C, some detergents may not dissolve properly, reducing their effectiveness in cleaning clothes. This can leave detergent residues on fabrics, leading to a less thorough wash.
• Washing Machine Build-Up: When you wash at lower temperatures regularly, detergent residues and bacteria can accumulate in your washing machine. Over time, this may lead to unpleasant smells or even mold growth within the drum and hoses.

What Temperature Should You Wash At?

To get the most out of your washing machine and ensure both cleanliness and disinfection, consider the following guidelines:

1. Wash Bedding, Towels, and Underwear at 60°C: For these items, a hot wash is recommended to kill bacteria, dust mites, and germs. Towels and sheets, in particular, benefit from the disinfecting power of higher temperatures.
2. Cold Water for Delicates: For delicate fabrics such as wool, silk, and certain synthetics, cold water (around 30°C) is usually best. Cold washing reduces the risk of shrinking or damaging these fabrics, while still removing dirt effectively.
3. Use the Right Detergent: If you must wash at 40°C, make sure to use a high-quality detergent designed to work in lower temperatures. Some modern detergents are formulated to break down stains and bacteria at cooler temperatures.
4. Occasional Hot Washes: Even if you typically wash at 40°C for energy savings, consider running an occasional hot cycle (at 60°C) with your towels or gym clothes to remove bacteria and keep your washing machine fresh.

The Bottom Line

While 40°C might seem like the perfect middle ground for laundry, it’s important to understand its limitations when it comes to cleaning power and hygiene. For more effective cleaning, particularly if you’re concerned about germs, allergens, or stubborn stains, washing at higher temperatures—such as 60°C—can make a significant difference. However, balance is key: remember to also wash delicate items in cooler water and avoid over-washing at high temperatures to preserve the longevity of your clothes and fabrics.

By reassessing your laundry routine, you can ensure your clothes are truly fresh, clean, and free from harmful microorganisms. So, the next time you load up the washing machine, think twice before selecting that 40°C setting—it might not be as effective as you think!