Group 1 - Different locations of white hair reflect various health issues: white hair at the forehead is related to spleen and stomach, at the temples is associated with liver and gallbladder, and at the top and back of the head is linked to kidney health [1][22] - White hair at the forehead is primarily due to spleen and stomach disorders, often caused by fatigue or excessive eating leading to stomach heat [2] - White hair at the temples is connected to liver and gallbladder dysfunction, often resulting from staying up late, stress, or blood deficiency in women [3][4] Group 2 - White hair at the top and back of the head is associated with kidney deficiency, which may also present symptoms like lower back pain and hair loss [8] - Various remedies are suggested for each type of white hair: for forehead white hair, a mixture of Poria, dried tangerine peel, and Job's tears is recommended [2][5]; for temple white hair, a blend of sophora flower, peony root, and bamboo leaves is advised [5]; for top and back white hair, a mixture of black rice, black beans, and black sesame is suggested [9][10] Group 3 - The concept of "white hair injection" is commercial and not clinically proven to reverse white hair, with potential causes for early white hair including genetics, stress, and nutritional deficiencies [11] - It is advised not to pluck white hair as it may damage hair follicles, while cutting them is a safer option [12][13] Group 4 - Four hair care tips are provided: use gentle shampoo, adjust washing frequency based on hair type, avoid high water temperatures, and limit hair dyeing [13][14][16][18] - A balanced diet rich in protein, zinc, iron, and vitamins is recommended, along with adequate sleep and regular scalp massages to promote hair health [19][20][21]

Core Viewpoint - The article emphasizes that proper hair washing techniques and the selection of effective ingredients are crucial for hair health and growth, rather than relying solely on new shampoos [1]. Group 1: Hair Washing Techniques - The effectiveness of shampoo ingredients requires sufficient contact time with the scalp, typically 3-5 minutes for active components like caffeine and saw palmetto [2]. - Washing frequency should be tailored to individual needs; for oily scalps, washing every 1-2 days is recommended, while dry scalps can extend to 3-5 days [3]. - Proper scalp cleaning is essential, involving techniques such as using warm water to open hair cuticles and massaging the scalp to enhance blood flow by up to 20% [4]. Group 2: Active Ingredients in Shampoos - Salicylic acid, a beta-hydroxy acid, is effective in removing scalp oil and dead skin cells, suitable for oily scalps, and should be used 1-2 times a week [5]. - Caffeine has been shown to inhibit hair follicle miniaturization and promote hair growth by increasing energy signals within follicle cells [5]. - Herbal ingredients like cedar leaf and he shou wu (fo-ti) can improve scalp circulation and prolong hair growth phases, with specific usage recommendations for their extracts [7].