Protein vs. Moisture: Here's How to Tell Which One Your Hair Needs to Beat Damage

Damage isn't discerning. It can strike regardless of hair type. Do you color-treat your hair? It could be damaged. Do you heat-style your hair? Yep. What about travel? Have you exposed your hair to things like sun, heat, or salt water? All of these things can lead to split ends, dryness, dullness, and rough texture—the trademarks of damaged hair.

If you're like me, and you're on a journey of treating and reversing hair damage, you'll need to know what products and ingredients will benefit your hair the most. In other words, you'll need to know whether it needs protein or moisture. You see, protein and moisture are the two most critical components of healthy, shiny, expensive-looking hair, so when one (or both) is thrown out of balance, you see dreaded signs of damage appear. Ahead, learn how to tell if your hair needs protein or moisture. Then, see the best protein- and moisture-rich products to use.

The Basics of Protein and Moisture

Helen Reavey is a celebrity trichologist, hairstylist, and the founder of the scalp-care brand Act+Acre. She says to think of moisture and protein as the foundation of healthy, resilient hair—"one without the other leads to imbalance." Celebrity hairstylist Joey Scandizzo agrees, saying, "Your hair needs both moisture and protein so it can remain healthy and strong."

Both protein and moisture play specific roles in the hair strand. The former gives it strength and volume, whereas the latter gives it shine, softness, smoothness, and elasticity. Take it from Reavey, who says, "Protein strengthens the hair shaft by reinforcing its structure," she says. "Moisture keeps the hair soft, flexible, and smooth."

Jessica Hallock is a hairstylist, salon owner, and founder of Ensemble Hair. She says that, simply put, protein strengthens the hair and moisture protects the hair. "Protein can provide amino acids, which helps create keratin to strengthen the cuticle as well as generate hair growth." Moisture, on the other hand, "helps build that outer layer of protection around the cuticle to prevent split ends and withstand heat. Oftentimes, we reach for reparative products when we notice our hair is dry, when in reality we just need to replenish the moisture to get our hair back to look and feel the way we want.”

How to Tell Which One Your Hair Needs

It's easy to say that your hair needs both protein and moisture, but what if you notice damage and you can't tell which one it's lacking? Luckily, the pros have some tips for figuring it out before you spend time and money purchasing a damage-reversing hair product. Start by analyzing how your hair looks and behaves. The experts say there are signs to look out for. See some of the most common ones below.

Your hair is most likely lacking protein if you see…

• Weakness
• Limpness
• Shedding
• Tangles
• Breakage/split ends
• Excessive stretchiness
• A "mushy" feeling

Your hair is most likely lacking moisture if you see…

• Dryness
• Dullness
• Roughness
• Brittleness
• A "straw-like" feeling

Hallock has a three-step system to diagnosing your hair at-home. "See, touch, and test." Start with the first one. "Does it look dull? Does it have shine? Are there a lot of broken pieces? Do you have split ends? Does your natural curl or wave stay curled evenly or have some of your curls turned straight or stretched? If you notice your hair is dull, or your natural curl is not how it used to be, then you fall into the needing moisture category. If you notice a lot of broken pieces and or experiencing split ends pretty frequently, then you fall into the needing protein category.”

Next, touch your hair to assess it's texture. "Has your texture changed? Did it use to be soft and now it feels coarse? Is there a lot of static when you run your fingers through your hair? Does it constantly tangle? If your texture has changed and/or it feels more coarse than soft, then we need to address adding protein. If you’re experiencing static and constant tangling, and there is a difference in softness from your mid strand to ends, then we need to add more moisture."

The Stretch Test

Hallock says the third step is to test the strands (Reavey refers to this as the stretch test). "This tells us how well the hair can handle being under stress, whether it’s color services, tension, or heat styling," Hallock says. Here's how it works. Take a single strand of wet hair and gently stretch it. "If it stretches a lot and feels almost gummy before snapping, it needs protein," Reavey says. "If it feels stiff and breaks with little to no stretch, it needs moisture. If it stretches slightly and bounces back, it’s balanced."

When I tried the stretch test, I found that my hair was stiff and brittle to the touch. In fact, the ends of my hair would often break off from the rest of the strands as I was stretching them. It was a clear sign that my hair needed moisture rather than protein. That got me thinking: What are the best moisture- and protein-rich hair products for treating and reversing damage? Keep scrolling to find out!

The Best Protein-Rich Hair Products

If your hair needs protein, Scandizzo, and Reavey recommend looking for the following ingredients: hydrolyzed soy, rice, wheat, and pea protein. "It’s important to look out specifically for wheat, pea, soy, or rice proteins," Scandizzo says. There's also wattleseed (a natural source of protein in Australia), hydrolyzed silk protein, amino acids, and collagen. The latter "helps fortify hair strands and boost overall thickness," Reavey says.

Hallock says the two most common ingredients for protein are keratin and biotin, but she doesn't recommend reaching for those. "Unfortunately, so many of our products have these two ingredients in them, which leads to an over-saturation of protein and can actually do the opposite from what we are trying to achieve. Instead, I recommend finding products that incorporate amino acids to assist in building keratin."

The Best Moisture-Rich Hair Products

Hallock, Reavey, and Scandizzo say you want to look for ingredients that will both add moisture (humectants) and seal it into the hair strand (emollients) if you're dealing with dry hair. Common ingredients include hyaluronic acid, glycerin, aloe vera, avocado oil, shea butter, rosemary extract, and green tea extract.