Cortisol and other stress-related steroids can be measured in hair, providing a long-term indicator of hormone levels over weeks to months. This method differs from traditional blood and saliva tests, which capture short-term fluctuations. While hair analysis offers unique insights into chronic stress, research is still ongoing to fully understand how these measurements compare to those from blood and saliva, as factors like hair growth and external influences may affect results.
Hair Sample Collection Instructions
Materials Needed:
• Aluminum foil (cut into sheets as specified by the lab)
• Scissors
• Paper clip
• Sectional hair clips (appropriate size for securing hair)
• Comb
• Gloves
• Plastic bags that seal tightly to hold multiple foil packets (Ziploc)
• Cotton string (12-inch lengths, non-slip, and thick enough to securely tie around a hair section without loosening)
Preparation:
1. Lay out all materials: scissors, hair clips, comb, and pre-cut aluminum foil.
2. Prepare the string:
• Fold a piece of string in half.
• Tie a slip knot to create a loop approximately 2 inches in diameter.
• For reference, this video demonstrates how to tie a slip knot: How to Tie a Slip Knot.
Hair Collection Procedure:
3. At the back of the head, lift and secure a top layer of hair using the hair clips.
4. Approximately 2 cm below the cranial bone, use the comb to separate 2-3 strands of hair. Overall diameter of strands should be about half of a pencil.
5. Thread the selected hair strands through the loop of the string and tighten the loop securely.
6. Cut the hair as close to the scalp as possible, ensuring the tightened string remains around the sample.
7. Place the cut hair sample at the center of a piece of aluminum foil, keeping the string intact.
8. Place the strands of hair on the foil in the center, leaving the string on the sample. Using a permanent marker, mark on the foil which end of the sample was the end cut (and closest to the scalp). If the hair sample is too long for the foil, the strands can be trimmed at the end that was farthest from the scalp.
Foil Wrapping Procedure:
8. Wrap the hair sample carefully in foil:
• Fold about 1 inch of the foil over the scalp end of the sample.
• Fold the left side over the hair, then fold the right side to meet the left fold.
• Fold about 1 inch of the bottom of the foil up to secure it.
• Do not fold the hair itself.
9. Secure the foil-wrapped sample with a paper clip at the scalp end.
10. Label the sample:
• Attach the participant label to the foil.
• Place the labeled foil packet into a sealable plastic bag (e.g., Ziploc bag).
11. Storage: Store the sample in a dark, dry location until ready for shipping.