No, lemon itself does not straighten hair. While lemon juice has some properties that might indirectly affect hair's appearance, it does not chemically alter the hair's structure to make it straight.
How Lemon Juice Affects Hair
Lemon juice contains citric acid, which has a slight cleansing and potentially straightening effect when used in conjunction with other ingredients. The reference stating that "Lemon juice has a cleansing and straightening effect" should be interpreted cautiously. This effect is likely indirect, as it might temporarily smooth down the hair cuticle, giving the illusion of straighter hair. However, this is not a permanent straightening effect like that achieved with chemical treatments.
A diluted lemon juice rinse (pH 4-6) can help the hair cuticle lay flat, which can improve shine and manageability, potentially making the hair appear slightly straighter. However, the actual hair structure remains unchanged.
Several references mention using lemon juice in combination with other ingredients, such as coconut milk or oil, for hair treatments. These recipes often aim for hair conditioning and softening rather than permanent straightening.
Important Note: Using lemon juice on your hair, especially in direct sunlight, can lead to significant damage and lightening of hair color, as the citric acid acts as a natural bleaching agent. This is not hair straightening; it is a bleaching effect.
In summary: Lemon juice does not straighten hair in the way chemical relaxers or keratin treatments do. While it may contribute to a temporary smoothing effect due to cuticle flattening when used in conjunction with other conditioning agents, it will not permanently change the hair's natural texture.
