It is not inherently bad to use heat protectant spray everyday although it's not recommended to use heat protectant everyday.
It's best to use heat protectant only on days when you're applying heat to your hair with hair styling tools including blow dryers, curling irons and hair straighteners.
Excessive buildup of the heat protectant can occur when you use it daily.
You should also ideally only do heat styling a few times a week to prevent heat damage to the hair even with heat protectant.
The heat protectant spray that is best is EVA NYC mane magic 10 in one primer.
I use the EVA NYC mane magic 10 in one primer with great results and love it and it also provides you with UV protection and also has a great smell.
Living Proof's Restore Perfecting Spray is also good for heat protectant as well.
It's a lightweight and hydrating formula that leaves your hair feeling bouncy as well as shiny and it ensures full heat protection while styling your hair.
To not get heat damage to your hair you should use a heat protectant spray that you apply to the hair before you use a hair dryer or other hair styling tools.
The heat protectant spray protects your hair from heat damage by allowing the heat to distribute evenly through the hair.
Also avoid using the heat styling tools in one location too long to avoid heat damage.
Or use heatless styling methods for your hair like foam rollers, air drying or braiding.
And use heat styling tools with a variety of different heat settings and use the lowest heat setting possible.
Heat damaged hair will look like dry, dull, frizzy and rough hair.
When hair is heat damaged it will also tend to have visible split ends and often feel brittle and break easily.
The heat damaged hair may also have a knotted or tangled texture and lack shine and be very difficult to style as a result of the damaged cuticles which no longer reflect light properly.
If you have curly hair that is heat damaged the heat damaged curly hair may also lose it's curl definition and appear limp and straight hair that is heat damaged may look and appear unmanageable and also lack any sleekness.
To fix your heat damaged hair you can use a heat protectant and moisturize your hair and reduce heat styling.
If using blow dryers, curling irons or hair straighteners you should use a heat protectant.
Or use heatless styling methods for your hair like foam rollers, air drying or braiding.
And use heat styling tools with a variety of different heat settings and use the lowest heat setting possible.
Heat damaged hair is not permanent because the heat damage to the hair does not damage or affect the hair follicle.
Although it can take time for the heat damaged hair to return to it's healthy state of not being damaged.
Heat damage to the hair alters your hair's protein bonds and cuticles.
The heat damaged hair can also become frizzy, dull and dry and become more prone to breakage.
And split ends are a common symptom of heat damage.
Flyaways are also short strands of hair which break off near the roots.
In most cases heat damaged hair should fix itself within 2 to 3 months in which the hair should heal from the heat damage.
However if your hair is more heat damaged it may take around 6 to 12 months for the hair to heal from the heat damage and fully heal and return to normal.