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Common hair dyes and henna often contain chemicals and metals that may harm your hair in the long run. Using natural solutions to darken your hair color will allow you to not only avoid possibly harmful substances, but to use environmentally friendly alternatives. Substances such as coffee, black tea, ground cocoa and sage work to naturally dye your hair.

Brew a strong pot of black tea, either with loose tea or two or more tea bags in boiling water. Strain. Let it cool completely before applying to your hair. Let the tea soak in for an hour before washing off.

Stir a mixture of yogurt and a teaspoon of ground coffee. Stir this mixture into a cup of cold, strongly brewed coffee. Apply the mixture to your hair and let it sit for about an hour before rinsing off.

Mix half your shampoo with ground, unsweetened cocoa. Lather the mixture into your hair as you would when normally shampooing. Do this daily to retain your dark hair color.

Add 1 cup of dry sage into 2 cups of boiling water and let it sit for at least 8 hours. Apply to hair and let the mixture sit until hair is dry. Rinse off.