The food you eat plays a critical role in hair health, and one macronutrient that may be particularly helpful for hair growth is protein.
Most of your hair is made up of protein, specifically a protein called keratin. The protein you get in your diet can help your hair grow and stay healthy, says Shani Francis, MD, board-certified dermatologist and chief wellness officer and medical director of Ashira Dermatology.
Here’s everything you need to know about protein for hair growth, including the relationship between protein and hair loss, the best protein-rich foods for healthy hair, and whether protein shakes and powders are good for hair growth.
How Does Protein Contribute to Hair Growth?
Your hair needs amino acids, the building blocks of protein, to grow. While your body can make 11 of the 20 amino acids, the remaining 9 — called essential amino acids — come from food. That’s why eating protein is key to hair growth, in addition to supporting overall hair health, says Dr. Francis.
Lack of protein can also contribute to hair loss. According to a review of research on hair loss and growth, you may experience hair loss if your diet is low in complete proteins, which contain all nine essential amino acids.
What’s more, biotin, a B vitamin found in protein you eat, helps metabolize amino acids and can support strong, healthy hair, says Francis — though you probably don’t need biotin supplements unless you’re deficient in it, according to research.
Protein is key to supporting healthy muscle tissue, and your body will prioritize that over hair growth, Francis says. So if your body isn’t getting enough protein to maintain basic muscle function, your hair will suffer first, she says.
But keep in mind that some hair loss is normal — most people lose between 50 and 100 hairs per day, according to the American Academy of Dermatology.
Other Causes of Hair Loss
Protein restriction can certainly lead to hair loss, says Francis. But according to the American Academy of Dermatology, other factors can also contribute to thinning hair. So before loading up on protein, you may need to work with a doctor to rule out other potential causes, such as:
- High levels of vitamin A
- Low iron
- Thyroid disease
- Scalp infection
- Stress
- Medication side effects
How Much Protein Do You Need for Healthy Hair?
Protein deficiency is rare in the United States — even among those who follow vegetarian and vegan diets, according to the T. Colin Campbell Center for Nutrition Studies.
Still, it’s important to make sure you’re getting enough of the nutrient. According to the U.S. Department of Agriculture’s 2020–2025 Dietary Guidelines for Americans, women need at least 46 grams (g) while men need around 56 g for hair growth and overall health.
It can take about two to three months of not getting enough protein to start noticing hair loss, according to Cleveland Clinic. According to UCLA Health, other signs of protein deficiency, which may help you identify it as a cause of hair loss, include:
- Brittle hair
- Brittle or thinning nails
- Fatigue or weakness
- Mood changes and brain fog
- Frequent illness or infection
Eating protein can help with hair loss, Francis says. So if you consistently have a hard time getting enough and are experiencing thinning hair as a result, work with your doctor or a registered dietitian to create an eating plan that includes plenty of high-protein foods.
What About High-Protein Hair Products or Topical Protein?
Research suggests topical protein treatments — like products containing keratin — could improve the quality of existing hair and help prevent breakage, but there’s no evidence to suggest they can promote hair growth.
The best way to encourage hair growth with protein, according to research, is from the inside out — through nutrition.
Protein-Rich Foods for Healthy Hair
The best way to harness protein for hair growth is to get it through whole food sources, according to Cleveland Clinic.
You can get a good dose of protein from the following foods, according to Harvard Health Publishing:
- Fish
- Lean poultry like chicken
- Eggs
- Dairy products like low-fat yogurt and cottage cheese
- Nuts and nut butters
- Seeds
- Legumes like beans and lentils
- Whole grains like whole-wheat pasta and quinoa
- Soy products like tofu and tempeh
These foods can provide the complete proteins your body needs to perform normal functions, including hair growth. Keep in mind that one serving size of animal protein is about 3 ounces, or the size of a deck of cards, in most cases.
Animal products — including chicken, fish, and bone broth — also contain large amounts of another type of protein naturally made in our bodies called collagen, according to Cleveland Clinic.
A research review suggests your body can use the amino acids in collagen to create keratin, supporting strong hair.
Protein Supplements for Hair Growth
Although Francis recommends getting your nutrients from whole foods whenever possible, she says what’s most important is getting enough protein, period. “Some people choose protein bars or shakes, and if it’s easier for them to get protein that way, I don’t discriminate.”
According to Cleveland Clinic, some people may benefit from supplementing their diet with protein powder, including those who:
- Are trying to build muscle
- Are recovering from injury or surgery
- Need to put on weight
- Need extra nutrition due to underlying illness
Adding a protein powder to your meals could also help you get your daily dose if food alone isn’t cutting it. This may help reverse symptoms of a deficiency, like hair thinning or loss.
However, protein powder isn’t a miracle hair loss cure: It’s unclear if protein supplementation helps your hair grow if you don’t have a deficiency in the nutrient, especially since little research exists to support this claim.
Still, Francis stresses the importance of getting enough protein. One popular supplement is whey protein, a type of protein found in milk. It typically comes in the form of powder that you can add to drinks, oatmeal, yogurt, and other dishes.
Various types of protein powder can help you meet your needs, including many plant-based formulas. It’s important to look at all of the ingredients to make sure you’re getting a complete protein, meaning it has all the essential amino acids that can help with hair loss.
Whey protein is generally safe to eat, but some people should avoid it, including those who are allergic to milk, lactose intolerant, or sensitive to dairy, notes Harvard Health Publishing.
If shakes are your preferred form of protein, you can still pick or make ones with natural sources of the nutrient. These recipes can help get you started.
Can Whey Protein Cause Hair Loss?
Perhaps you’ve heard that whey protein induces hair loss or negatively impacts hair, but there’s no evidence to suggest you can experience hair loss from protein powder alone.
While protein powder doesn’t cause hair loss, whey protein may have some other side effects such as digestive upset. In general, though, it’s safe to eat for those who can tolerate it.
