Why You Should Rethink Your Shampoo Ingredients

For decades, shampoo has been marketed around shinier hair, bigger volume, and fewer bad hair days. Rarely has the conversation focused on the scalp itself or the ingredients behind those promises. But as ingredient transparency becomes a bigger priority across wellness, more people are starting to rethink the products they use every wash day.

The scalp requires specific care

Carly Ferrarese, founder of Under Luna, has built her brand around that very idea. She says the future of healthy hair starts with the scalp, which she describes as skin that has many of the same needs as facial skin. Ferrarese believes people have historically viewed hair care as cosmetic while skincare became synonymous with self-care and ingredient awareness.

“Haircare has traditionally focused on surface-level results: more shine, more volume, less frizz,” Ferrarese explains. “But scalp care asks a different question: what’s happening at the root?” She notes that people are becoming less interested in quick fixes and more interested in understanding the underlying causes of issues like excess shedding or flakes. The connection between hormones, inflammation, gut health, stress, and diet often shows up through the scalp.

Historically, the hair care industry has prioritized the visual appearance of hair over the biological health of the scalp. This focus on immediate results like shine and volume often overlooks the root causes of hair concerns. In contrast, a scalp-first approach treats the scalp as a living organ that requires specific care to function properly. By addressing the scalp, the hair itself becomes healthier, leading to more sustainable results than surface-level treatments.

Defining truly non-toxic hair care

Many consumers are starting to realize that “clean” doesn’t always mean transparent. For Ferrarese, “truly non-toxic hair care starts with the ingredients.” She explains that her brand was born from a need for shampoo and conditioner she could feel good about using. Under Luna focuses on formulas where every ingredient has a purpose and nothing is hidden behind vague claims.

Ferrarese avoids adding ingredients as fillers or choosing items because they look good on a label. She works with trusted suppliers and sources many locally grown herbs. The brand does not rely on buzzwords like “clean,” “natural,” or “non-toxic” without a clear definition behind them. Instead, the company focuses on formulas that are transparent, thoughtful, and support the scalp and hair.

Under Luna’s formulas lean heavily on herbs and roots like white willow bark, horsetail, yarrow, chamomile, and yucca root. Ferrarese did a tremendous amount of research before creating her first shampoo samples. She kept coming back to questions about what shampoo really is and how people used it before the industry became commercialized.

Yucca root and the search for balance

Yucca root is one ingredient that appears throughout Under Luna’s shampoos and isn’t something most consumers are familiar with. Traditionally, yucca root was crushed or worked against stone to release its natural saponins, creating a gentle, soap-like lather. What makes yucca different from many cleansing agents is that it helps cleanse without stripping the scalp of its natural oils.

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Our shampoos are designed to remove dirt, buildup, and excess oil while still protecting the scalp barrier and supporting pH balance. This is why yucca appears throughout the shampoos. It is gentle, effective, and foundational to the way the company formulates.

Ferrarese avoids synthetic fragrance, harsh surfactants, silicones, and preservatives that do not meet her standards. Fragrance is a big one because it can hide undisclosed aroma compounds under a single word. She also avoids harsh cleansing agents that can strip the scalp barrier and leave people stuck in a cycle of dryness, irritation, and overproduction of oil. Silicones are another category she avoids entirely because they can create the temporary feeling of softness and shine while masking what the hair and scalp actually need.

Shampoos designed for specific scalp needs

Under Luna’s shampoos each seem to support different scalp needs and hair textures. The company starts with the scalp, designing shampoos around those needs while conditioners are designed around the needs of the hair itself. Because the shampoos are built around intelligent plants, different herbs are layered in depending on the type of support the scalp needs.

For someone who is more oily or dandruff-prone, the brand created Warrior Shampoo with herbs traditionally used to decongest the scalp and help rebalance oil production. For someone experiencing dryness, sensitivity, or irritation, Luna Clear Shampoo leans into herbs known for their soothing and restorative properties. For balanced or fluctuating scalps, especially during periods of hormonal change like pregnancy, postpartum, and perimenopause, the brand created Tulsi Bloom Shampoo.

The goal isn’t to aggressively correct the scalp but to help bring it back into balance. Warrior Shampoo was the very first formula created for the scalp that feels oily, congested, itchy, or dandruff-prone. Ferrarese wanted to create something that could deeply cleanse and help rebalance the scalp without stripping it. People with oily or flaky scalps often reach for harsh shampoos that over-strip the scalp, leaving it feeling tight, irritated, and even more reactive. Warrior was designed to support that cycle differently, to help lift buildup, calm a flaky, itchy scalp, and leave it feeling clean, balanced, and like it can breathe again.

If readers take away just one thing from this conversation, Ferrarese hopes they become more in tune with their scalp. The scalp tells a story. Just like people learn to read their skin, they can begin to read the scalp in the same way. Oiliness, flakes, itch, buildup, sensitivity, or shedding can all be signals worth paying attention to.

When under stress, she often notices a small dry patch appear right at her hairline. It serves as a reminder that the scalp is part of an incredible system and often reflects what is happening internally. When a routine is nourishing and supportive, washing your hair isn’t something to avoid. It becomes something you can turn to when your scalp feels out of balance. The more people learn to listen to their scalp, the more they understand what it needs and what their body may need, too.