Using oil alone may not be enough to hydrate and moisturize your hair, especially if your hair is naturally dry or damaged. While oil can help to seal in moisture and protect your hair from environmental factors, it may not be enough to provide the hydration that your hair needs.
To effectively moisturize your hair, you need to use products that contain both water-based ingredients and emollients (such as oils or butters). Water-based products can penetrate the hair shaft and provide deep hydration, while emollients can help to seal in that moisture and prevent it from evaporating.
It's also important to consider the type of oil that you are using. Some oils are better at penetrating the hair shaft than others. For example, coconut oil and olive oil have been shown to penetrate the hair shaft and provide deep conditioning benefits, while lighter oils such as argan oil or grapeseed oil may not be as effective.
In addition to using the right products, it's important to maintain a healthy hair care routine that includes regular washing and conditioning, as well as minimizing heat styling and protecting your hair from environmental factors. Drinking plenty of water and eating a healthy diet can also help to promote overall hair health and hydration.