Dry skin type vs dehydrated skin: How to tell the difference

Key takeaways:

• Dry skin is a skin type, while dehydrated skin is a health condition. 
• Dry skin and dehydrated skin share similar symptoms—skin that looks dry, rough, and sometimes itchy—but they mean different things. The difference between dry and dehydrated skin lies in what causes them.
• Dry skin is often associated with skin conditions like eczema, certain medical issues like kidney problems, and lifestyle factors. Genetics may also be blamed for it. On the other hand, dehydrated skin is primarily a result of the body not having enough water, possibly because it loses more water than it gains.
• A skin turgor test can help tell if a person's skin is dehydrated. However, this test isn't always reliable, so you should see a doctor if you think you're moderately or severely dehydrated. 

Dry skin and dehydrated skin are often used interchangeably; however, they're not the same. Dry skin is a skin type, while dehydrated skin is a symptom of dehydration. People with dry skin generally produce less skin oil (sebum) than people with normal skin, and their skin lacks the ability to retain moisture.

Any skin type (both normal and oily skin types) can become dehydrated when there is inadequate water intake or excess fluid loss (without proper replenishment). 

Since dry skin isn't a disease, it typically has no cure; however, it can be managed. Dehydrated skin, on the other hand, can be resolved with adequate treatment, which primarily involves taking in water and other healthy fluids like soup. 

Differences between dry skin type and dehydrated skin

The table below summarizes the differences between dry skin and dehydrated skin.

What causes dry skin?

Studies show that some people may have a genetic predisposition to dry skin. This is due to variations or mutations in the FLG gene. The FLG gene provides instructions for making a protein called profilaggrin, which is found in cells of the outermost layer of skin (the epidermis).  

The filaggrin protein is involved in producing molecules that are part of the skin's "natural moisturizing factor," which helps maintain skin hydration. The protein also plays an important role in forming the skin’s strong barrier to reduce water loss and protect the body from harmful microorganisms and substances that cause allergic reactions like eczema. 

When there are mutations in the FLG gene, the functions of the filaggrin protein, including its ability to protect against skin allergies and ability to keep the skin moisturized, become impaired. This is why dry skin is also linked to skin conditions like eczema, especially in people with this genetic mutation.

Aside from this, other things can contribute to dry skin, such as:

• Aging: Sebum is a type of oil produced by a sebaceous gland in the skin that helps keep the skin moisturized. The body starts producing less amount of sebum as a person gets older, and according to the American Academy of Dermatology, most people at 60 years have dry skin.
• Medications: Dry skin is a side effect of certain medications, like diuretics and statins.
• Occupation: Some jobs like hairdressing, housekeeping, and construction work that involve the use of harsh chemicals often cause dry skin.
• Smoking: The harmful chemicals in cigarettes cause the skin to age quickly, and so one's skin becomes dry.
• Chemotherapy and radiotherapy: These cancer treatments can cause one to develop very dry skin.
• Diseases: Different health conditions, like diabetes, HIV, kidney disease, and anorexia, can also cause excessively dry skin.
• Skin conditions: Certain skin conditions like eczema, psoriasis, and ichthyosis can be linked with dry skin.  

What causes dehydrated skin?

Losing more water than you're taking in and, ultimately, low body fluid results in dehydrated skin.

The following are potential causes of insufficient fluid in the body which may lead to dehydrated skin:

• Vomiting and diarrhea: The body loses fluids this way, which causes dehydration and can affect the skin.
• Drinking an insufficient amount of water: Reduced water intake or not drinking enough water prevents the body from replenishing the fluid it loses through sweating and urinating. 
• Medications: Diuretics, a type of medication that causes one to lose water, can cause dehydrated skin.
• Excessive sweating: This could be due to exercising or working outdoors in very hot weather. 
• Impaired sense of thirst: When the body needs water, it causes one to feel thirsty. People whose thirst mechanism is impaired tend to drink little water, which causes them to be dehydrated. Old age is a risk factor for an impaired sense of thirst. Hence, older people tend to drink less water.
• Certain illnesses: Kidney problems that cause one to lose excess fluids through urination can cause one's skin to become dehydrated.  

How to tell whether you have dry or dehydrated skin

It can often be difficult to distinguish between dry skin and dehydrated skin. However, certain symptoms make one more likely than the other. To be certain, see a dermatologist or your family doctor. 

The following symptoms are indications of dry skin:

• Rough skin texture 
• Cracks in the skin, especially at the back of one's feet
• Shedding or peeling of one's skin
• Raw and painful skin
• Loose and wrinkled skin
• Itchy and scaly skin, especially on the arms and legs 
• It is usually associated with eczema or psoriasis 

Here are some symptoms that may indicate you have dehydrated skin:

Dehydration doesn't just cause dry and itchy skin or fine lines on the skin. It usually occurs with the following:

• Dry mouth
• Sunken eyes
• Fever
• Reduced sweating and urinating
• Feeling of thirst
• Loss of skin elasticity

The skin tugor test

Skin elasticity, also known as skin turgor, can be used to show that one's skin is dehydrated. A skin turgor test is usually done by a doctor, but you can also do it at home if you're worried that you might be dehydrated. Below are the steps to check for skin turgor:

• Use two fingers to pinch your skin.
• Pinch the skin on the lower arm or abdomen. 
• Hold the pinched skin for a few seconds. 
• Then let go and observe how quickly your skin returns to its initial position. 

If your skin is not dehydrated, it will immediately return to its initial position after a skin turgor test. However, if there's moderate to severe dehydration, the skin doesn't immediately return to its normal position; rather, it takes a few seconds. 

The skin turgor test isn't a definitive test for dehydrated skin, so you should see a doctor if you have concerns about your skin.

The best skincare products for moisturizing dry skin

Moisturizers that contain ceramides, urea, hyaluronic acid, lactic acid, or glycerol in the right amounts can help keep the skin hydrated. Some moisturizers that are great for dry skin include:

1. CeraVe Moisturizing Cream: This moisturizer adds and preserves more water in the skin than the lotion. Some of its ingredients are ceramides and hyaluronic acid, which help lock in moisture.
2. Neutrogena Hydro Boost Water Gel Moisturizer: This skin moisturizer contains active ingredients like hyaluronic acid and glycerin, which are good for dry skin. Dermatologists recommend it, and the reviews are great.
3. Cetaphil Moisturizing Cream: This cream contains glycerin, petrolatum, and other active ingredients for dry and sensitive skin types. It is also fragrance-free and hypoallergenic.
4. Aquaphor Healing Ointment: This uniquely formulated ointment contains glycerin and petrolatum. Dermatologists sometimes advise using it because it is great for dry, cracked skin.
5. Vanicream Moisturizing Cream: The Vanicream moisturizer contains petrolatum and is ideal for dry, sensitive, and eczema-prone skin. It doesn’t clog one's pores. It also has the National Eczema Association seal of acceptance.

How to treat dehydrated skin

Since dehydrated skin is caused by dehydration, its underlying cause, which is dehydration, has to be treated in order for the skin to get back to the right hydrated state. 

Consider speaking with a healthcare professional if you suspect you are dehydrated or show symptoms of dry skin. If you are indeed dehydrated, your treatment will depend on the severity of your condition. In the meantime, ensure you are taking enough water, as your body needs water to thrive.

For mild dehydration, do these:

• Drink lots of water. The Institute of Medicine of the National Academies recommends that adult females drink up to 2.7 litres of water (11 cups) daily and about 3.7 litres (15 cups) for adult males.
• Use oral rehydration solutions (ORS) for children. 
• Take small sips of water if you're vomiting.

For moderate-to-severe dehydration, healthcare providers will often take these lines of action:

• Rapid replacement of fluids: Normal saline or other types of fluids can be given intravenously to the patient at the hospital.
• Proper diagnosis: Doctors may need to identify the main cause of dehydration and have it addressed.
• Checking for fluid levels and vital signs: Blood pressure, heart rate, and the volume of urine produced may be monitored to determine how much fluid has been lost and how effectively treatment is going. 

To have healthy skin, use the appropriate moisturizer for your skin type, drink adequate amounts of water, and avoid using chemicals that could harm your skin.