The Science of Frizz in the Winter

Winter can be beautiful, but for our hair, it’s often the most challenging time of year. Cold air, indoor heating, and cozy hats might keep us warm, but they can leave hair dehydrated, damaged, and frizzy. Understanding the science behind these environmental changes helps us better support our hair health and keep frizz under control all season long.

Changes in the air.

Healthy hair depends on moisture balance. When the air gets cold, its ability to hold water vapor decreases dramatically, which makes it drier.¹ That dry air pulls moisture from the surface of the hair, leaving strands parched and prone to frizz. Indoor heat adds another layer of dryness, further stripping hair of hydration.

When hair loses moisture, the friction between dry hair strands produces static, causing individual hairs to repel one another and create stubborn flyaways.² Over time, the combination of dryness, static, and daily wear and tear leads to microscopic changes that weaken and roughen the cuticle, further contributing to tangling and frizz.³

Fabrics.

When choosing winter hats and scarves that touch your hair, consider two things:

Synthetic fibers like polyester tend to build more static than natural fibers, and textured fabrics create more friction than smooth weaves.^4-6

Most hair-friendly:

Good alternatives:

Less ideal:

The bottom line: For fabrics that sit directly against your hair, smoother is better. When choosing a hat, opt for one lined with a smooth material. Silk is the gold standard, with other smooth weaves as very reasonable alternatives. 

Diet.

Diet changes during the holidays also play a role. Higher intake of sugar, simple carbs, and alcohol can disrupt the balance of nutrients that support healthy hair growth and moisture retention.^7–11 Diets high in sugar can lead to resistance to insulin, which in turn can negatively impact hair health.^10,11

Porosity.

Not all hair reacts to winter the same way. A key factor is porosity, or how well hair absorbs and retains moisture. Hair porosity depends largely on the outermost layer of the strand, the cuticle, which is made of overlapping keratin scales, much like roof shingles, which vary across hair types.¹²

Straight hair tends to have a flatter cuticle that provides better moisture retention. Curly, coily, or damaged hair has a more lifted cuticle layer.³ That means high-porosity hair, whether naturally curly or chemically processed, loses moisture more easily and becomes frizzy more rapidly in dry winter air.

Structure. 

Curly and coily hair types face another challenge: their structure. Because of the twists and turns of the hair shaft, natural scalp oils can’t easily travel from root to tip, leaving ends dry and less protected from moisture loss. Even if sebum production at the scalp is normal or high, the lack of even distribution makes curly/coily hair more prone to dryness and frizz.³

When moisture enters and exits hair repeatedly, such as with humid-to-dry winter transitions, it can cause “hygral fatigue,” or repeated swelling and drying of the strands. Over time, this weakens the cuticle, increasing breakage and frizz.³ Understanding your hair’s porosity and structure can help you choose the right protective steps for the season.

Caring for strands.

Since the only living, active part of hair is the hair follicle, hair strands can’t repair themselves once damaged. Topical care and gentle habits can go a long way in visibly restoring smoothness and reducing breakage.

High-quality conditioners can help protect hair during the winter. They work by temporarily filling in tiny fractures in the cuticle and coating the strand, thus regulating moisture retention, smoothing the cuticle’s surface, and minimizing friction.¹³ Protein-based conditioners with amino acids or hydrolyzed proteins can also penetrate the strands to strengthen and fortify them more deeply.^3,13 

Equally important is minimizing friction and mechanical stress. Avoid harsh chemical treatments, aggressive brushing, and over-washing, all of which can strip or weaken the cuticle.³ 

Taking an internal approach.

Finally, nourish your hair from within. Balance winter comfort foods with options rich in protein, healthy fats, and vitamins. High-quality protein, such as meat, poultry, dairy, beans, nuts, and seeds, provides the amino acids cysteine and methionine, which are needed for keratin synthesis.¹⁰ Omega-3 fatty acids from fish, flaxseed, and walnuts help maintain the lipid layer that seals in moisture.¹⁰ Foods rich in B Vitamins, like leafy greens, beans, and whole grains, along with vitamin A (beta-carotene) from foods like carrots and sweet potatoes, support balanced oil production, protecting hair against fragility and frizz.¹⁰

Nutrafol Hair Growth Nutraceuticals provide targeted support for stronger hair from within, offering ingredients that balance oil, support healthy hair and hydration, and can help support against the stressors of the winter environment.

For external support, Nutrafol’s Strand Defender Conditioner is a lightweight, physician-formulated conditioner with glucose fibers and vegan protein to strengthen and defend hair against damage. It’s clinically tested to replenish moisture and improve elasticity, helping hair stay smooth and strong.¹⁴

Active Cleanse 2-in-1 Shampoo & Conditioner for men is physician-formulated for the bio-specific needs of men’s scalps, replenishing hydration and detangling without weighing hair down. It’s designed to strengthen and improve the visible health and quality of the hair.^15,16

Winter frizz isn’t a flaw in your hair—it’s simply a response to the environment during this time of year. Thankfully, you can take steps to reduce the impact on air, temperature, friction, and diet on your hair. An inside-and-out approach to hair care in the winter can go a long way in helping keep your locks smooth and resilient all winter long.