Dr. Khanna: “It’s a pleasure to be here. The answer is quite simple, yet profound. Hair follicles are among the most metabolically active cells in the body. [5, 16] They are constantly in a cycle of growing, resting, and shedding. This high rate of cellular turnover requires a steady and rich supply of nutrients. Think of your hair follicles as tiny factories. If you don’t provide them with the right raw materials—proteins, vitamins, and minerals—production slows down, and the quality of the final product, your hair strand, suffers. A poor diet can lead to brittle, dull hair, slowed growth, and even significant hair loss. [1] So, truly, the journey to healthy hair begins on your plate.”

Dr. Khanna: “First and foremost, protein. Hair itself is made up almost entirely of a protein called keratin. [1] If your diet lacks adequate protein, your body will ration it for essential functions, like organ repair, and hair production will be put on the back burner. [26] This can lead to a condition called telogen effluvium, where hair shifts prematurely into the shedding phase. [16] Ensuring you have high-quality protein sources at every meal is the cornerstone of any hair-healthy diet. This includes lean meats, poultry, fish, eggs, dairy, and for plant-based individuals, legumes, tofu, quinoa, and nuts.” [25]

Dr. Khanna: “Next up is iron. Iron deficiency, with or without anemia, is a major and often overlooked cause of hair loss, particularly in women. [16, 27] Iron is essential for producing hemoglobin in your blood, which carries oxygen for the growth and repair of cells, including the cells that stimulate hair growth. [13] When your iron levels are low, oxygen delivery to your follicles is impaired, disrupting the hair growth cycle. Great sources of easily absorbable heme iron are red meat and oysters. [13, 4] Plant-based non-heme sources include lentils, spinach, and fortified cereals, which should be consumed with a source of Vitamin C, like citrus fruits or bell peppers, to dramatically enhance absorption.” [5, 27]

Dr. Khanna: “Biotin, or Vitamin B7, is famously marketed for hair growth. It plays a key role in producing keratin. While a true biotin deficiency is rare in those with a balanced diet, ensuring you have enough is important. [1, 21] You can find it in eggs, salmon, sweet potatoes, and almonds. [1, 4] But it’s not just about biotin; other B-vitamins like Folate (B9) and B12 are also critical. They help create red blood cells, which, as we discussed with iron, are the oxygen carriers for your entire body, including your scalp and follicles.” [24, 25]

Dr. Khanna: “Zinc is a powerhouse mineral for hair health. It plays a crucial role in hair tissue growth and repair. It also helps keep the oil glands around the follicles working properly. [26] Hair loss is a classic symptom of zinc deficiency. [28] Oysters are the most potent source of zinc, but you can also get it from beef, pumpkin seeds, and lentils. [6, 7] Selenium is another vital trace mineral that acts as an antioxidant, protecting against oxidative stress, and is involved in hair production. Brazil nuts are an incredible source—just one or two a day can meet your daily requirement. But be cautious, as too much selenium can also cause hair loss.” [Source Needed]

Dr. Khanna: “Absolutely. It’s one thing to know the nutrients, but another to know the foods. Here are ten of my top recommendations:”

1. Eggs: The perfect package of protein and biotin. [1, 4]
2. Berries: Loaded with hair-protective Vitamin C and antioxidants. [1]
3. Spinach: A fantastic source of folate, iron, and Vitamins A and C. [1, 4]
4. Fatty Fish (like Salmon): Packed with omega-3 fatty acids, protein, selenium, and Vitamin D. [1, 5]
5. Sweet Potatoes: Rich in beta-carotene, which the body converts to hair-moisturizing Vitamin A. [4, 7]
6. Avocados: An excellent source of Vitamin E, which supports scalp health, and healthy fats. [6]
7. Nuts and Seeds: Think almonds for Vitamin E, walnuts for omega-3s, and pumpkin seeds for zinc. [5, 8]
8. Oysters: The undisputed champion of zinc. [4, 6]
9. Beans and Lentils: A superb plant-based source of protein, iron, zinc, and biotin. [1]
10. Greek Yogurt: High in protein and Vitamin B5 (pantothenic acid), which helps with blood flow to the scalp. [4]

Dr. Khanna: “Critically important. It’s often the missing link. Water makes up almost a quarter of the weight of a single hair strand. [23] Dehydration can immediately halt hair growth. [2] When you’re dehydrated, your body prioritizes water for vital organs, and your hair follicles get cut off. [2, 23] This can lead to dry, brittle hair that is prone to breakage and a dry, itchy scalp which is not a healthy environment for growth. [13, 18] Proper hydration ensures that nutrients are efficiently transported to the hair follicles. Aiming for at least 8 glasses, or about 2 liters, of water per day is a foundational step in the best diet for hair growth.” [22]

Dr. Khanna: “Yes, definitely. The main culprits are sugar and highly processed, simple carbohydrates. [22] A diet high in sugar leads to spikes in blood sugar and insulin. This can increase androgen (male hormone) activity, which can cause follicles to shrink, leading to a condition known as miniaturization and eventual hair loss. High sugar intake can also create an inflammatory environment in the body, which is not conducive to healthy hair growth. [22] Additionally, excessively low-calorie and restrictive crash diets are a disaster for hair. They can trigger massive shedding (telogen effluvium) because the body goes into survival mode and shuts down non-essential functions like hair production.” [Source Needed]

Dr. Khanna: “This is a key part of any interview with a nutritionist on the best diet for hair growth because it’s such a common question. My philosophy is always ‘food first.’ Whole foods provide a complex matrix of vitamins, minerals, fiber, and phytonutrients that work synergistically in a way a single pill cannot replicate. [30] Supplements can be very useful to correct a diagnosed deficiency, like low iron or Vitamin D. [28] However, taking them without a deficiency is often unhelpful and can sometimes be harmful. For instance, as I mentioned, excessive Vitamin A or selenium can actually cause hair loss. [16, 27] So, supplements can be a targeted tool, but they are not a substitute for a consistently nutritious diet. Always consult with a healthcare provider before starting any new supplement regimen.”

Dr. Khanna: “Absolutely. Diet is paramount, but it doesn’t exist in a vacuum. The number one factor is stress. [3, 9] Chronic stress elevates cortisol levels, a hormone that can push a large number of hair follicles into the resting (telogen) phase, leading to noticeable shedding a few months later. [10, 11] Managing stress through mindfulness, exercise, or therapy is crucial. Secondly, lack of sleep. Sleep is when our body undergoes repair and regeneration. Poor sleep disrupts hormonal balance and cellular repair processes, which can impact your hair cycle. Aim for 7-9 hours of quality sleep per night. Finally, be gentle with your hair. Harsh chemical treatments and excessive heat styling can cause physical damage that no diet can fix.” [14]

Dr. Khanna: “This is where patience is key. Hair growth is a slow process. On average, hair grows about half an inch per month. [17] Since the changes start at the follicle, under the skin, it will take time for that new, healthier hair to grow out and become visible. You might start to notice less shedding and improved scalp health within 2-3 months. [10] To see a noticeable difference in the length, thickness, and shine of your hair, you should give it at least 6 months to a year of consistent effort. It’s a long-term commitment, not a quick fix. But the results are not just better hair; they’re a better, healthier you.”