This deep conditioner is aimed at people with dry, curly or damaged hair who need a periodic protein-and-moisture treatment, for example after braids, twists, heat styling or frequent detangling has left strands weak or brittle.

Because it's a straightforward apply-wait-rinse treatment rather than a leave-in or multi-step protocol, it suits both first-time deep conditioner users and more experienced curl-care routines that already alternate protein and moisture treatments.

The main reason to reach for this over a plain moisturizing conditioner is the amino-acid content: hair that's been through braiding, twisting or regular heat styling loses protein along with moisture, and a conditioner built around glycine, alanine, serine and related amino acids is meant to replace some of that lost protein at the same time the babassu and acai oils replace lost lipids, rather than treating dryness and protein loss as two separate problems.

Best used right after shampooing, while hair is still clean and damp.

• Section damp, freshly shampooed hair into four parts.
• Apply the conditioner generously from root to ends in each section.
• Leave on for 15 minutes, or sit under a dryer for about 30 minutes for a more intensive treatment.
• Rinse thoroughly with cool water and style as usual.

The conditioner's strength is its amino-acid and oil combination: babassu, acai and pracaxi oils supply fatty acids for slip and shine, while the run of amino acids (glycine, alanine, serine, valine and others) works as a light protein boost, and the formula is flexible enough to use as a quick 15-minute rinse-out or a 30-minute heat-assisted treatment for more damaged hair.

The trade-offs are the fragrance load and the mint: peppermint, spearmint and grapefruit oils give the tingling, cooling sensation some users like, but that same essential-oil blend can be irritating for a fragrance- or mint-sensitive scalp, and the 8 fl. oz. bottle is on the smaller side for anyone using it as a regular weekly treatment on long or thick hair.