Woman brushing her hair
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Your hair's thickness naturally starts to wane in your mid-20s. Smoking, excessive heat and chemical treatments can make the unwanted change even more pronounced. It's tough to permanently thicken hair, but that doesn't mean you need to live with fine, limp locks. A flattering haircut or new color can give thin tresses instant volume. Pair your style with body-boosting products for a look you'll love.

Shampoo

Your quest for thicker hair starts in the shower with the right shampoo. Shampoos formulated for fine hair work by adding volume and strengthening weak strands. Buy a shampoo that's labeled "thickening" or "volumizing." If you have gray tresses, look for a product that's made for that hair type, as all-purpose thickening shampoos may not work as well for gray hair. Some shampoos also contain conditioner that smooths and softens hair. Alternatively, after shampooing, apply a leave-in conditioner so your hair stays voluminous all day.

The Right Cut

If you like layered hair, ask a stylist to cut the bottom layer of hair 1/2 inch shorter than the top layer. Have the stylist give the ends of your hair a blunted look. This makes your mane look fuller. Bangs are an option if you have thick hair in the front but thinner strands at the crown. Ideally, keep your hair cut above shoulder length. Longer hair looks thinner then tresses cut into a shorter style. Whichever cut you choose, don't let your stylist use a razor on your hair -- it can fray the ends.

Add Color

Coloring your hair makes it look thicker than it really is. Peroxide, used in many hair dyes, doubles the thickness of hair strands. Highlights give hair texture and creatures the illusion of fullness. If you have bangs, dye the bottom layer two shades darker than the rest of your hair to make them seem thicker. Permanent dye may weaken your hair, so consider using a semi- or demi-permanent color instead. Consult a salon stylist if you're not sure what colors look best on you. If you'd rather experiment or save money, use an at-home dye kit.

Styling Tips

To add instant volume to your mane, spritz damp roots with a lifting spray or apply a dab of volumizing mousse. Smooth a thickening cream from the middle of your hair strands to the ends. Look for thickening creams or sprays that contain Lilly Pilly, an Australian antioxidant that gives hair body. Avoid gels and heavy products that can weigh hair down. Let your hair air-dry until it is 80-percent dry before continuing with a blow-dryer, and then part your hair differently than how you intend to wear it before you do blow-dry, as this will add volume when you flip your hair into its usual spot. You can curl your hair at the roots to add fullness, and you can also use large hot rollers to roll up 1-inch-wide sections of hair at the top part of your head. Twist the rollers 180 degrees and use plastic clips to hold them in place. Remove them after 20 minutes.