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Unlocking the Secrets of Healthy Hair: Proteins and Bonds

Aug 15, 2023

Have you ever wondered what makes healthy hair strong, bouncy, and gorgeous? Proteins and bonds are the strand superheroes that give hair strength, flexibility and shine. Let’s dive into the world of proteins and bonds to learn why they are the key to shinier, smoother, and softer hair—and discover how you can rescue your hair when heat, styling, chemicals and environmental assault start to unravel those bonds.

The Building Blocks of Amazing Hair

Your hair is mainly made up of a structural protein called keratin that gives it strength, flexibility, and structure. (It’s what makes your skin and fingernails healthy, too.) Keratin, like all proteins, is built of long strings of amino acids called polypeptide chains. There are 18 different amino acids bound into the polypeptides that in turn bind to form the keratin protein.

When hair looks and feels dull and brittle, it is often an indication that the bonds between the amino acid building blocks of hair’s essential keratin have been disrupted. Amino acid rich haircare—like Bond Repair Intensive Leave-In Treatment Masque—is designed to replenish hair to help repair damage, strengthen strands, and reduce breakage.* Before we go too far down that rabbit hole, let’s take a closer look at the role of keratin proteins in supporting your hair’s structure and health.

Breaking Down the Three Layers of Hair

Think of each strand of hair as an onion with three layers. The outermost layer is the cuticle. A protective shield, it’s made up of tiny scales that overlap and guard the inner layers. These scales are formed by a keratin protein layer, and they play a vital role in keeping your hair soft and safe from damage. When the cuticle is smooth and intact, your hair shines and looks healthy. When it’s damaged or lifted? Hello, dullness and frizz!

Underneath the cuticle is the cortex, which is the middle layer of your hair. This is where the action happens. The cortex is packed with more keratin proteins that give your hair strength, flexibility, and its unique color. The way these proteins are arranged in the cortex determines your hair’s texture, thickness, and even how it curls. It’s the backbone of your hair!

At the very center of the strand is the soft and spongy medulla. Some people (often those with fine hair) actually don’t have a medulla—which is totally okay because we’re still not quite sure about its exact role! Experts think it might contribute to the overall flexibility and resilience of your hair.

The lesson here: You want your cuticle, the outermost layer of keratin proteins, to remain smooth and intact so it protects the rest of your hair from damage.

Bonds in Hair: The Magic That Holds It All Together

So where do bonds come into play? Bonds lock hair’s proteins together on a molecular level. They provide the electrochemical force that links individual amino acids into long polypeptide chains and in turn links those molecular chains into keratin proteins. There are three types of chemical bonds that work hard to keep your hair strong and healthy.

First up are the mighty disulfide bonds (or covalent bonds), the strongest and most abundant bonds in your hair. They form when two sulfur atoms, found in certain amino acids of keratin, get cozy and create a bond. They’re essential for providing strength and resilience. But beware! Chemical treatments, excessive heat styling, and even environmental factors can break these bonds, leaving your hair weakened and damaged.

How Do Disulfide Bonds Work?

  • Formation: Disulfide bonds form when the sulfur atoms in two cysteine amino acids, present in the hair’s protein structure, come in close proximity and bond together.

  • Strength: Disulfide bonds are incredibly strong, providing the hair with its tensile strength (resistance to breakage). They are responsible for maintaining the hair’s shape and resilience when faced with stretching, bending, and heat.

  • Chemical treatments: Chemical processes such as perming, relaxing, or coloring hair rely on the disruption and reformation of disulfide bonds. By breaking these bonds and then reforming them in a new arrangement, it is possible to alter the hair’s texture or color. Disulfide bonds can only be reformed under a chemical process like a perm or extreme heat like a flat iron up to 450°F.

The second type of bonds are the trusty hydrogen bonds. They aren’t as strong as disulfide bonds, but they play a crucial role in your hair health. Hydrogen bonds form between water molecules and the protein chains in your hair. They’re responsible for your hair’s elasticity and temporary shape—that’s why your hair can change shape when wet or during heat styling. These bonds are easily disrupted by water or heat, so always handle your hair with care!

How Do Hydrogen Bonds Work?

  • Formation: Hydrogen bonds are temporary and easily broken or reformed with changes in moisture, temperature, or pH levels. When hair is wet or exposed to humidity, the water molecules disrupt the hydrogen bonds, causing the hair to become pliable.

  • Styling impact: Hydrogen bonds are responsible for the temporary changes we make to our hair, such as styling with hot tools or using wet-setting techniques. Heat or moisture from styling tools or products can break the hydrogen bonds, allowing the hair to be reshaped. Once the hair cools or dries, the bonds reform, holding the new shape temporarily.

  • Importance in perm and curling processes: When hair is permed or curled, the disulfide bonds are first broken, allowing the hair to become more flexible. The hair is then wrapped around curlers, and hydrogen bonds are formed between adjacent hair strands, creating the desired shape. Neutralizing the hair reforms the disulfide bonds, locking the hair into the new curled pattern.

Lastly, we have salt bonds, also known as salt linkages or ionic bonds. These bonds form when positive and negative ions attract each other. They’re not as strong as disulfide bonds, but they still contribute to your hair’s structure and stability. The pH of your hair products can affect these bonds, so it’s good to choose products that balance the pH for happy and healthy hair.

How Do Salt Bonds Work?

  • Formation: Salt bonds are influenced by pH levels. When hair is exposed to an alkaline environment (aka a high pH), the hydrogen atoms in the amino acid groups accept additional electrons, resulting in a positive charge. These positively charged amino acid groups attract and form bonds with the negatively charged amino acid groups in adjacent protein chains.

  • Impact on hair health: Salt bonds contribute to the overall strength and elasticity of the hair. They are easily disrupted by changes in pH levels, such as using alkaline hair products or exposure to chlorine in swimming pools. These disruptions can lead to weakened hair, causing it to become brittle, frizzy, or prone to breakage.

Love Your Hair, Love Yourself!

While the science behind hair proteins and bonds might be a bit complicated, finding a science-backed solution to restore strength, smoothness and shine to damaged hair couldn’t be easier. Alterna’s revolutionary Bond Repair Intensive Leave-In Treatment Masque is designed to transform damaged hair into healthy-looking hair after just one use. It dramatically strengthens and smooths hair, reduces and prevents breakage, and significantly improves shine, even after repeated washes*.

In addition to our exclusive Caviar Bond Enforcing Technology and Age Control Complex (which bathes strands in essential lipids, proteins and minerals), Bond Repair Intensive Leave-In Treatment Masque is infused with naturally derived amino acids to help moisturize, protect, and repair surface damage, fight frizz and create a glass-like shine. Reach for this all-in-one-treatment-masque whenever you notice damage to your hair. Just replace your conditioner with a pea-sized dab of the masque and activate it by heat styling. Learn exactly how to use it here.

Intensive Leave-In Treatment Masque is the newest addition to our Bond Repair collection, which is perfect for anyone looking for a hair glow-up. These multi-benefit products are designed to fight damage by helping to seal cracks and fissures in the cuticle, restoring smoothness strength and shine so hair looks healthier and more youthful. Try Caviar Bond Repair products in your haircare routine and then follow these tips to keep your hair healthy and looking fabulous:

  • Always treat your hair with love and care. Be gentle when brushing and styling. Avoid tight hairstyles that can strain your precious strands.

  • Follow a balanced diet with protein, vitamins, and minerals to nourish your hair from the inside out. Dig into lean meats, fish, eggs, legumes, nuts, fruits, and veggies!

  • Keep your hair hydrated by using moisturizing hair products and protecting it from excessive sun, heat, and harsh chemicals. Healthy hydration maintains the integrity of each strand’s cuticle for less breakage and more shine.

  • Regular trims are your hair’s best friend! Trims help prevent split ends and breakage to keep your hair looking and feeling healthy.

Remember, your hair is unique, just like you! Reach for products that restore your hair’s proteins and bonds, maintain a healthy lifestyle, and keep a positive attitude to look and feel your absolute best!

* Against combing breakage on untreated virgin healthy hair


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