There are several effective home remedies for gray hair available, which include the use of natural ingredients such as Indian gooseberries, neem oil, henna, amaranth, black tea and salt, ginger and honey, sesame, and chyawanprash. Other home remedies include a healthy intake of food containing protein, iron, vitamins, and the application of oils like coconut oil.
Home Remedies & Treatments for Gray Hair
There are several home remedies for gray hair that can be easily undertaken without burning a hole in your pocket. These home remedies include:
As hair is made up of a protein called keratin, a protein-rich diet will help increase its production and will improve hair growth. Protein is found in meat, eggs, and cereals, such as whole wheat and lentils. 
Vitamin and Mineral Intake
Vitamin A, vitamin B12, iron, copper, and zinc are some of the very important nutrients. Lack of these nutrients may also catalyze graying of hair. Food such as meat, poultry, fish (including shellfish), nuts, legumes, raisins, and prunes are good sources of these vitamins and minerals. 
Iodine is a must, to stop graying of hair. Iodine is the element that influences the thyroid gland. Any diseases of the thyroid gland such as hypothyroidism or hyperthyroidism can result in graying of hair. Iodine is not only found in salt, but also in other foods such as bananas, carrots, and fish. 
Mix three teaspoons of lemon juice with coconut oil then apply it to hair. Let your hair absorb it for around an hour and then wash your hair with a shampoo. Repeat the same process weekly and see improvement.
You can also use potato peel to darken your hair, as potato peel has starch in it, which directly helps in this process.
As we have already discussed how smoking leads to graying of hair, it is very important that you completely get rid of smoking from your life. This will not only be beneficial in reversing gray hair but will also have a good impact on your overall health.
Indian gooseberry, also known as amla in Hindi, is considered a wonder fruit. It is used to treat a variety of ailments in Ayurveda. The dried powder of Indian gooseberry mixed with coconut oil applied on the scalp can be good for reversing gray hair. Consumption of Indian gooseberry improves hair growth and is also good for digestion, respiratory disorders, diabetes, heart diseases, diarrhea, and dysentery. Excessive intake of raw Indian gooseberry is to be avoided. The best way to have it is in powdered form.  
The leaves of amaranth or amaranthus are known to be one of the best home remedies for gray hair. The extract from its leaves is helpful in restoring hair color. Apply juice of amaranth leaves to hair after shampooing and then rinse.
Black Tea with Salt
Applying black tea along with salt is a recommended remedy for gray hair. Take a cup of strong black tea and add a teaspoon of salt. Cool this solution and apply it to hair roots. Leave it for an hour and then rinse off. Do not shampoo it. 
Many people think this is grandma’s old trick, but studies have shown that the regular application of oils such as coconut oil help in reducing hair damage and slowing down graying of hair. 
Stress is also related to graying of hair. Avoiding or overcoming stress is very important in slowing down the process of graying. Regular exercise, meditation, spending quality time with family and friends can also help. 
Application of henna paste on hair is another popular home remedy for gray hair. A natural henna paste can be made directly by making a paste of henna leaves with yogurt and fenugreek seed paste. This paste can then be applied to the hair. It is also used for natural skin dying with no side effects that are usually associated with artificial hair colors.
In Ayurveda, the ancient science of Indian medicine is stated that a dried powdered mix of Bhringaraja (Eclipta alba), black sesame seeds, and Indian gooseberry in 2:1:1 proportion is good for the hair. This powder must be taken along with milk twice daily for positive results.
Ginger with Honey
Consumption of ginger and honey is also believed to be effective in treating gray hair. This mixture has often been prescribed in traditional Chinese medicine. 
A ribbed gourd is another remedy for gray hair. The vegetable should first be cut into pieces, should be shade-dried and boiled with coconut oil and the remaining black residue can be applied on hair roots. 
Butter made from cow’s milk is believed to be an effective cure for gray hair. Apply it to the hair roots. The enzymes in cow’s milk and butter are believed to prevent and reverse the process of graying. 
Neem or Azadirachta indica tree is of great significance in Ayurveda. The essential oil obtained from neem can be used as a remedy for various problems including gray hair. The oil is also helpful to eliminate head lice and dandruff. 
Sesame seeds, particularly black sesame seeds and sesame oil are also considered good for reversing gray hair, according to Ayurveda. Massage sesame oil on your scalp regularly. One can also include sesame seeds in their diet. 
Chyawanprash is an Ayurvedic preparation said to be prepared by a sage named Chyawan. It has fruit jam-like consistency. Up to 50 herbal, fruit, oil, and spices are added to this mixture. The final product gives various benefits including hair growth. A study conducted by Parle M and Bansal N has emphasized on the benefits of chyawanprash.  
Things to Avoid: Smoking, excessive tea, and coffee consumption, using strong detergents, very hot water and hot dryers on hair, and hair dyes at an early age are some of the things that can be avoided to prevent early hair graying.
With such remedies in hand, one can make sure that gray hair is a thing of the past.