From my experience, people think they know their skin type, but they don’t. In 80% of cases, they think their skin is dry, but it’s actually dehydrated.
What’s the difference, and why is this important to you?
First, because you need to be able to choose the right skin care products based on your TRUE skin type, otherwise skin problems (blackheads, bumps, oiliness, flaking, sensitivity) may arise.
Second, because product texture (serum vs. lotion vs. cream) is extremely important in making a skin type feel comfortable. If the product is too thick for your skin type, the skin feels and looks greasy (and can even cause more acne), if the product is too thin for your skin type, the skin feels tight, dry and looks parched and dull.
“Skin types are based on the amount of OIL they produce”.
Marie Bertrand, microbiologist & skin scientist
There are 4 different skin types:

1. DRY SKIN: by definition, dry skin is skin that is not producing enough oil. The skin can feel tight all day and you see skin flaking and lack of radiance. Pores are barely visible and there is no blackheads. (10% of the population).
SOLUTION FOR DRY SKIN: choose products that contain oils to compensate for lack of natural oils in the skin.
2. NORMAL SKIN: by definition, normal skin produces the right amount of oil – not too much, not too little. It is not super shiny at the end of the day, not dry and tight, it’s just perfect. Pores are normal and the blackheads are usually very small, if they are present. (10% of the population).
SOLUTION FOR NORMAL SKIN: maintain healthy skin and healthy amounts of oils.
3. COMBINATION SKIN: by definition, combination skin produces a different amount of oil in the T-zone then on the cheeks. There are different levels of combination skin. The T-zone can be oily and the cheeks normal, the T-zone can be oily and the cheeks dry. Overall, the Tzone produces more oil than other parts of the face and is shiny at the end of the day. Pores are more visible on the nose and cheeks, blackheads are usually visible. Combination skin is often associated with acne. (70% of the population).
SOLUTION FOR COMBINATION SKIN: do not add extra oils via skin care products. Look for oil-free and silicone-free products to hydrate skin.
4. OILY SKIN: by definition, oily skin produces an excess of oil all over. It can be very shiny a few hours after washing it in he morning. Large pores, blackheads and oiliness are characteristics of oily skin. (10% of the population).
SOLUTION FOR OILY SKIN: Avoid oil-based skin care products. Look for oil-free and silicone-free products to hydrate skin.
“All these skin types (dry, normal, combination, oily) should be differentiated from DEHYDRATED skin, which is by definition skin that lacks WATER or HYDRATION. In general, all skin types (dry, normal, combination, oily) can also be dehydrated (lacking water)”.
Marie Bertrand, microbiologist & skin scientist
As a rule of thumb, everybody experiences some level of dehydration no matter what their skin type is.
Problems arise when people who have combination/oily skin cleanse their skin and it feels tight and they think it’s dry. They then reach for products that are labelled for “dry skin” (ie: contain added oils to compensate for the dry skin condition) but adding oils on their skin will cause them to be shiny and breakout. Their combination skin is not dry, it’s simply dehydrated – so they need HYDRATION ie. additional water NOT additional oils.
Now that you can analyze your skin type, and if it is dehydrated or not, here are the ingredients you should be looking for to feel comfortable.

If you have true dry skin, you can reach for skin care products that contain ingredients from both the left and right columns. (oils are ok if you have true dry skin)
If you have normal, combination or oily skin, you should steer clear of ingredients for dry skin (left column) and look for ingredients from the right column.
In healthy skin,
If you have true dry skin, you can reach for skin care products that contain ingredients from both the left and right columns. (oils are ok if you have true dry skin)
If you have normal, combination or oily skin, you should steer clear of ingredients for dry skin (left column) and look for ingredients from the right column.
In healthy skin,
Marie
– See more at: https://skinscience.md/blog/Is+your+skin+DRY+or+DEHYDRATED%3F#sthash.LdIbUt4E.dpuf

