Micronutrients aren’t just good for your overall health. They directly influence your hair’s growth, strength, texture, and shine. Each phase of your hair growth cycle depends on having the proper nutrients available at the right time.
If your body is running low on protein, or even one key vitamin or mineral, your hair follicles can slow down, weaken, or shift into a resting (telogen) phase too early, leading to shedding, thinning, or stunted growth.
Protein: The Foundation of Strong Hair
When it comes to hair health, keratin is the backbone of your hair, making up 95% of each hair strand and giving it the strength, structure, and resilience it needs to grow and thrive.
Keratin is a fibrous protein made up of 18 left-chain amino acids, naturally produced by your body. These amino acids come together to create the tough, fibrous protein that makes up hair, nails, and the outer layer of skin.
Of all the amino acids, the most important ones for hair structure include:
- Cysteine is the most critical as it forms disulfide bonds that give hair strength and stability
- Methionine supports cysteine production
- Arginine improves blood flow to hair follicles
- Glutamic acid contributes to the hair’s protein structure
- Serine, glycine, proline, and tyrosine help form keratin’s helical shape
Cysteine makes up about 10–17% of your hair and plays a major role in how fast, thick, and strong your hair grows. But here’s the catch—your body can’t make cysteine without methionine. You need both working together to support healthy hair from the inside out.
In your hair, keratin forms the inner core and outer cuticle layer, helping:
- Strengthen the hair shaft
- Protect against damage
- Maintain shape, smoothness, and shine
This is why this powerhouse protein matters more than you think.
What Happens When Keratin Is Low?
When your body doesn’t have the right tools to produce or maintain keratin, you might notice:
- Frizzy or dull hair
- More breakage and split ends
- Thinning or loss of volume
- Slower growth or difficulty retaining length
Keratin loss can result from:
- Poor nutrition (especially low protein intake)
- Heat styling, chemical treatments, or harsh hair products
- Environmental damage, such as sun, chlorine, or pollution
- Hormonal imbalances or chronic stress
How to Support Healthy Keratin Levels
You can’t “apply” keratin from a bottle and expect lasting results unless you support it from within. Here’s how:
Eat Enough Protein
If your diet is low in it, your body will prioritize other organs before your hair. Focus on:
- Lean meats, eggs, and fish
- Legumes, lentils, and tofu
- Collagen or keratin protein supplements
If you’re not sure if you’re getting enough, you can check your daily needs using this Online Protein Calculator.
Get Key Amino Acids
These are found in:
- Chicken, turkey, eggs
- Nuts, seeds, and quinoa
- Protein powders with complete amino acid profiles
Avoid Overprocessing
Bleaching, heat styling, and excessive shampooing strip keratin from your strands. Use gentle products and heat protection to preserve the natural keratin layer.
Consider Keratin-Boosting Supplements
Supplements that combine keratin, MSM, collagen, and antioxidants can help support hair strength, especially post-surgery or during periods of shedding.
Omega-3 Fatty Acids: Nourish from the Root
Omega-3s are healthy fats that feed your follicles, reduce inflammation, and boost blood flow to the scalp. They can also help relieve dry, flaky scalp and improve hair shine and strength.
Antioxidant Vitamins: A, C, and E
- Vitamin A supports oil production in your scalp, keeping it hydrated and healthy
- Vitamin C helps your body produce collagen, a key component of your hair’s structure. It also boosts iron absorption
- Vitamin E improves blood circulation and protects hair from free radical damage
Together, these antioxidants help slow down the aging process, reduce hair loss, and support long-term scalp health.
B-Vitamins: The Energy and Growth Team
- Niacin (B3) increases blood flow to the scalp and supports keratin production
- Pantothenic Acid (B5) helps balance scalp oil and prevents premature graying
- Biotin (B7) supports keratin formation and improves strength and texture, especially if you’re deficient
- Folate (B9) helps produce red blood cells and regenerate follicle cells for healthy hair growth
- Vitamin B12 aids in oxygen delivery and supports thick, vibrant strands
Vitamin D: A Hair Growth Activator
Vitamin D plays a key role in activating your hair follicles and keeping them in the active (anagen) growth phase. Low vitamin D has been linked to several hair loss conditions, including androgenetic alopecia, telogen effluvium, and alopecia areata.
Iron: Fuel for Follicles
Iron helps carry oxygen to your hair roots and provides energy that powers the fast cell division that drives hair growth. A deficiency can lead to hair shedding, fatigue, and dull, lifeless hair.
Zinc: The Scalp’s Repair Crew
Zinc is essential for healthy oil production, tissue repair, and hormone balance. It also keeps inflammation under control. Low zinc levels are directly linked to thinning, shedding, and scalp issues.
Copper: The Color and Strength Mineral
Copper helps maintain your hair color by supporting melanin production and strengthens your strands by forming cross-links in keratin. It also improves blood flow and protects against oxidative stress.
Selenium: The Balancing Mineral
Selenium supports thyroid health, which affects the hair growth cycle. It also helps create antioxidant enzymes that reduce scalp inflammation. Too much or too little selenium can trigger hair problems, so balance is key.
Why Nutrient Deficiencies Trigger Hair Loss
When you’re low on vital nutrients, your body goes into conservation mode, redirecting energy and resources to vital organs. Hair isn’t essential for survival, so it’s often the first to suffer.
Deficiencies in nutrients like iron, certain B-vitamins, vitamin D, and zinc can throw off the hair cycle, leading to:
- Telogen Effluvium – excessive shedding.
- Alopecia Areata – autoimmune-triggered patchy hair loss.
- Slow or stunted growth, due to undernourished follicles.
Even worse, excessive intake of certain vitamins (such as A or selenium) can also cause shedding. The key is balance and personalization based on blood work.
