Microdermabrasion does work for many surface skin issues.
Microdermabrasion modestly rejuvenates skin and can reduce the appearance fines lines and wrinkles, pore size, hyperpigmentation, age spots, acne and acne scars, and stretch marks. 
How Microdermabrasion Works
Microdermabrasion is a procedure in which surface skin is exfoliated by the use of a special professional instrument. There are currently two methods by which this achieved, crystal and crystal-free. With crystal microdermabrasion, aluminum oxide is blasted onto the face through an instrument with suction. The crystals exfoliate the skin’s surface then the vacuum sucks up the crystals as well as the dead skin cells removed by the process. As this process tends to dry the skin, it is a good choice for those with oily skin. With crystal-free microdermabrasion, a diamond tipped instrument is used to exfoliate the skin. This method can exfoliate the entire face, but is beneficial in fine-tuning areas that may be difficult to reach with the crystal method, such as areas around the eyes and sinuses. 
Mechanism by Which Microdermabrasion Works
The microdermabrasion process abrades the skin causing the body to react as if it were healing a wound. During the wound healing process the body produces oxygen-rich red blood cells to build new tissue. It also stimulates collagen production. Collagen is a fibrous protein that determines the structure of the skin. As you age, collagen production decreases and the skin loses elasticity resulting in wrinkles and sagging skin. The increased collagen production produced by microdermabrasion help to remodel the outer layer of the skin. 
What Conditions Does Microdermabrasion Treat?
Note that microdermabrasion results in modest rejuvenation of the skin surface and seems to reduce the appearance of fine lines, pore size, and mild pigmentation. The procedure should not be expected to remove issues that lie deep beneath the surface of the skin.
Results will vary from patient to patient and will also vary based on the frequency that the procedure is performed. Exfoliating the surface layer of dead skin cells and the increased collagen production resulting from the microdermabrasion procedure can result in the reduction of the appearance of:
Hyperpigmentation. The body contains cells called melanocytes that produce melanin, which is responsible for the coloration of the skin. Exposure to sun, hormonal changes, or certain medications can cause overproduction of melanin causing such conditions as age spots, melasma, and chloasma. Several sessions may be required for desired results on age spots. Melasma and chloasma may see minimal lightening and may benefit from more aggressive procedures. 
Acne Scarring. When acne breakouts occur deep below the skin’s surface it can cause damage to the skin. Those with inflammatory acne and those that pick at their acne are at a higher risk of developing scars. Microdermabrasion may work for mild acne scarring by increasing collagen production to the scarred area. 
Fine Lines and Wrinkles. As you age the outer layer of the skin thins, you produce less collagen, and changes in the body’s connective tissue reduce strength and elasticity resulting in fine lines and wrinkles. Exfoliating the outer layer of skin coupled with increased collagen production can help to minimize their appearance.
Pore Size. A skin pore is the surface opening of the duct of a sweat gland. The average human has over 2 million sweat glands.  Anything clogging the pores tends to cause them to stretch and make them appear even larger. Microdermabrasion does not actually shrink the natural size of the pore, but it does help to clean out the pores, which in turn can help them to appear smaller. 
Microdermabrasion has also been shown to facilitate the absorption of topical creams, which can be beneficial for additional treatments and prevention.
Studies Measuring the Effects of Microdermabrasion
Several studies have been conducted to test the efficacy of microdermabrasion with positive results. For example, a 2001 study, published in the journal Dermatologic Surgery, analyzed the onset and extent of the dermatologic changes associated with microdermabrasion. Ten participants ranging from 31-62 years of age were given a series of six aluminum oxide microdermabrasion facial treatments. Compared to the control group that did not receive the treatments, the study concluded that the microdermabrasion produced a clinical improvement. 
A 2009 study published in the journal JAMA Dermatology investigated the dermal remodeling effects of crystal-free microdermabrasion on photodamaged skin. In this study, 40 adult participants aged 50-83 with photodamaged forearms, received microdermabrasion treatments with a diamond-studded handpiece of varying coarseness. They observed that the course grit treatments induced a wound-like healing response, which resulted in significant remodeling of the dermal layer of skin. 
When Microdermabrasion Does Not Work
Though this surface exfoliating procedure does help to reduce minor skin surface problems, it isn’t the cure-all for all skin issues. Result expectations should be based on the minimally invasive nature of the procedure. Those with unrealistic expectations are often disappointed in the results. It also should be understood that for microdermabrasion to realize full benefits, the procedure should be performed in several sessions. Deeper skin issues that are generally not resolved by microdermabrasion include:
- Deep Stretch Marks
- Inflamed Acne
- Capillary Damage
Who Is Not Eligible for Microdermabrasion?
Though a mild, non-invasive procedure, there are certain skin conditions that cannot tolerate microdermabrasion. The friction on the skin’s surface resulting from the microdermabrasion process stimulates the skin’s inflammatory response, which can aggravate conditions such as inflamed acne, rosacea, or those with capillary damage already present. 
Why People Choose Microdermabrasion
If you are looking for a quick, freshen-up, microdermabrasion may be a good option for you.
- Sessions usually last from 5 minutes to an hour
- No downtime
- Virtually painless
- Side effects rare
- Effective for most skin types
The question as to whether or not microdermabrasion works is open ended. Microdermabrasion does work as long as your expectations are realistic and understand what effects the procedure will produce. If you are looking to eliminate deep skin issues, another procedure would be preferable.
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