Questions for ‘The truth about zits’

P. acnes

P. acnes (dyed-purple squiggles above) is the most common type of bacteria on human skin. 

Bobby Strong/ CDC

To accompany feature “The truth about zits”


Before reading

1.    What’s a pimple and why does it form?

2.    Why do adolescents tend to have more breakouts than adults?

During reading

1.    What share of people will ultimately suffer from acne at some point?

2.    Why can washing your face too much make acne worse?

3.    How do whiteheads and blackheads differ in terms of their cause?

4.    Why are adolescents at greater risk for acne breakouts, and what is the potential role of hormones?

5.    What is ribotyping?

6.    What did scientists learn about the different acne bacteria from their ribotyping studies?

7.    What is a retinoid and why is it sometimes useful in treating acne?

8.    What is photodynamic therapy?

9.    Why is photodynamic therapy sometimes useful in treating breakouts?

10. What are probiotics and why might they be promising in treating acne?

After reading

1.    Look up the definition of an infection. Do acne breakouts seem to fit the explanation of an infection? Explain your argument.

2.    Explain the role inflammation can play in acne. Now read up on inflammation. Name four other medical conditions you learned about for which inflammation is an important feature.


1.    The story identified how many people in every 20 will develop acne at some time? Convert this proportion to a percent. Show your work.