Final answer:
The vacuum machine should not be used on dry and sensitive skin, as it can cause irritation and damage the skin barrier. It can be used cautiously on oily and acne-prone skin with care to avoid excessive suction.
Step-by-step explanation:
On what skin type would you not use the vacuum machine?
The vacuum machine is a skincare device that is commonly used to unclog pores by suctioning out dirt, oil, and other impurities from the skin. However, it is not suitable for all skin types. The vacuum machine should not be used on dry and sensitive skin as it can cause irritation, redness, and even damage the skin barrier.
For oily and acne-prone skin, the vacuum machine can be used cautiously, but it should be used with care to avoid excessive suction that could lead to skin damage. It is always important to consult with a dermatologist or skincare professional before using any new skincare device.