Nutritional deficiencies, stress, and certain medical conditions can all contribute to changes in hair shape, texture, and thickness. Stress can cause premature graying due to the reduction of pigment-producing cells in hair follicles. Alopecia areata, a condition where the immune system attacks hair follicles, is also linked to stress and thyroid disease. Cushing’s syndrome, which is caused by excess cortisol production in the body, can lead to brittle and easily breakable hair. Low iron stores or anemia can also result in hair loss and should be addressed by consuming iron-rich foods like seafood, spinach, red meat, and nuts. Protein deficiency is another common cause of thinning and hair loss that can be remedied by incorporating protein sources like yogurt, beans, chicken, and nuts into your diet. Consulting with a doctor about treatment options is recommended for individuals with poor digestion or a history of gastric bypass surgery who may struggle with protein absorption.