What causes new hair growth?
Nov 28, 2025
Source: Cainiu Health
Dr. Liu Wenmin
Introduction
Adequate nutrient supply: When the body receives sufficient nutrients such as protein, B vitamins, vitamin C, zinc, and iron, it provides the necessary building blocks for hair follicle growth. For example, protein is the main component of hair, and B vitamins are involved in hair metabolism. With adequate levels of these nutrients, hair follicle activity increases, promoting the growth of new hair.
New hair growth may generally be caused by factors such as hair follicles entering the growth phase, sufficient nutrient supply, restored regular作息 (daily routine), relieved stress, and improved scalp environment. The specific reasons are analyzed below:
1. Hair follicles entering the growth phase: Hair follows a natural cycle of growth, regression, and resting phases. When hair follicles exit the resting phase and enter the growth phase, new hairs gradually emerge. This initially appears as fine, soft vellus hair on the scalp, which later thickens and darkens—a normal physiological process.
2. Adequate nutrient supply: Sufficient intake of nutrients such as protein, B vitamins, vitamin C, zinc, and iron provides essential building blocks for hair follicle development. For example, protein is a primary component of hair, while B vitamins play a role in hair metabolism. When these nutrients are abundant, follicle activity increases, promoting new hair growth.
3. Restored regular daily routine: Chronic sleep deprivation disrupts endocrine rhythms, negatively affecting hair follicle health and leading to hair loss. When daily routines become regular again and 7–8 hours of sleep are consistently obtained, hormone levels stabilize, follicles receive adequate rest, and their normal growth function resumes, resulting in new hair growth.
4. Stress relief: Prolonged mental stress activates the sympathetic nervous system, inhibiting hair follicle growth and triggering hair loss. When stress is reduced through methods like exercise or meditation, nervous system regulation returns to normal, the inhibition of follicle growth is lifted, and new hair gradually begins to grow.
5. Improved scalp environment: Excessive sebum production or inflammation on the scalp can impair follicle health. By properly cleansing the scalp and treating inflammatory conditions, sebum buildup and bacterial proliferation are reduced, improving the scalp's microenvironment. Once follicles regain a healthy state, they can support new hair growth.
In daily life, it's important to maintain a balanced diet rich in nutrients essential for hair health. If abnormal hair shedding or slow growth occurs, one should pay attention to scalp condition and consult a professional when necessary.
