Sweat Science: Finding Your Invisible Pores
Ages 3–9
Q-bo's Answer
Your body has millions of tiny coolers! Use a safe test to see exactly where your sweat glands are and learn how they keep you cool.
📖 Explanation
🧒 For Ages 3-5 (Simple Words)
When you get hot, tiny holes in your skin called pores let out water to cool you down—just like a sprinkler on a hot day! Today we'll make those invisible holes show up as purple dots.
🎒 For Ages 6-9 (Scientific Explanation)
How Sweat Cools You Down
Your skin has about 2–4 million eccrine sweat glands. When your body gets too hot, your brain sends a signal and these glands release sweat (mostly water and salt). As the water evaporates off your skin, it carries heat away—this is called evaporative cooling.
The Iodine-Starch Reaction
Iodine normally looks orange-brown, but when it touches starch it turns dark blue-purple. When you sweat on the starch-dusted skin, the moisture reacts with both the iodine and the starch, creating a purple dot right over each active sweat pore.
🧪 Mapping Your Sweat Glands
~30 minUse iodine and starch to turn sweat into dark purple dots.
🛒 Supplies
📋 Steps
- 1
🖌️ Apply the iodine
Paint a small patch of your palm with iodine solution and let it dry completely.
- 2
🏃 Starch and Sweat
Dust the area with cornstarch. Jog in place for 2 minutes. Look for dark purple dots appearing!
Watch the Video
How antiperspirants keep you dry - sweat glands
Sweat Science: Finding Your Invisible Pores