Will My Skin Care Products Go Bad If Left In The Heat?

heat and your skincare products

What happens if your skincare products get hot?

If you shop from our website, your order is shipped directly from our warehouse in Austin, Texas. If there are two words that can describe Texas, it’s HOT SUMMERS. (And fall, too!) This means that the box we ship to you may sit in a hot mail truck for hours and depending on where you live, it also might sit on your doorstep in the heat. What if your cleanser or moisturizer is a thinner consistency when it first comes out of the box? Are they ruined?

The answer is no. Heat should not affect the performance of your skin care products. Let me explain why.

How a skincare product is made to hold up against heat

It’s important to know what goes into how a product is made. When products are made in a certified laboratory, chemists will do what is called the “oven test.” This is where a product is put into an oven with temperatures around 115 degrees Fahrenheit with 70 percent relative humidity. The products are kept in there anywhere from six weeks to three months. The purpose of the oven test is to determine if a product can stay stable and maintain its integrity since products can often be left in hot mail trucks or in less-than-desirable conditions. Heat can also mimic the long-term shelf life of a product to determine if the product will remain constant for a two-year shelf life and if the ingredients will separate or change consistency. All of the Renée Rouleau products go through this oven test, exposing them to heat over long periods of time to ensure their safety, performance, and longevity. So when your skincare products get hot, this should not affect the product at all.

Note: The oven test does not factor in UV light, so if a product sits out for long periods of time in UV light or sunlight, this most likely will weaken the performance of ingredients such as antioxidants and sun protection (which tend to break down in light). So definitely keep your products in a closed cosmetic bag and try not to subject them to long periods in the sun.

Not all skincare products are made in the same way

The type of skincare products that may not be made to hold up in hot conditions include:

  • “All natural” products
  • Small batch products that are meant to be refrigerated and used up quickly
  • Homemade products made in a kitchen that you might find on sites like Etsy

Many products certainly do not undergo rigorous testing for stability so this is something to keep in mind or inquire about before you make a purchase.

I can speak for my own product line. When the Renée Rouleau skincare products get hot, you don’t need to worry about their performance being affected. We’ve got you covered in all of life’s inevitable situations.

I hope you found this helpful! Want to learn more about products? Find out if your skin can get used to products and stop working!


Post a comment
  1. Avatar

    I still have a question, I have some products from the sisley collection and they say it’s all natural! But I left it in my car and it hot overheated:(
    It smells a tiny bit off but can I still use it?

    Posted By: Chloe  | 

    • Renée Rouleau

      Hi Chloe, it’s hard for me to comment on other products since I am not involved in their formulation. I would reach out to Sisely’s customer support for the most accurate answer!

      Posted By: Renée Rouleau  | 

  2. Avatar

    PERFECT timing!!! I have been wondering about leaving products in my car…by accident of course!! : )

    Posted By: tracy  | 


Post a Comment:

Find your
skin type

Great skin starts with knowing your skin type. Take our quiz to get personalized tips and product recommendations.

Take the Quiz