First of all, be reassured it is an impression, it is rare that this phenomenon occurs. It can occur in case of dysregulation often due to diseases. On average, hair grows 1 cm per month, that may be more for the lucky ones
So why is your hair always the same length?
Your hair is growing but you can't see it because you have more hair that breaks than hair that grows. This scenario is very common among women who resort to aggressive chemical techniques such as the use of relaxers or bleaching products. This is why it is recommended to perform this type of service at an experienced hairdresser. He will be able to decide if your hair can handle the application of these products. He can also advise you on another softer technique.
You may have noticed the hair is wearing out: heating devices or simply friction on clothing tend to weaken the hair fiber. To prevent this wear, don't forget to apply a few drops of serum on your lengths, very effective in protecting your hair, (we said a few drops do not pour the entire bottle :-)).
Care, care, care! The drier your hair is, the more likely it is to break. I strongly recommend that you buy your treatments in specialized shops, some hair salons can also offer them to you. The products found in supermarkets are often low in active ingredients and inefficient.
Food has an important part
We can't say it enough drinking water is the best moisturizer. A varied and balanced diet will be a plus for better health of your hair, and for better health in general ... Favor foods rich in zinc, such as seafood, calf's liver, lentils, etc.
Many brands offer food supplements based on iron, vitamin B6 and zinc. They can help you boost your metabolism.