There are two main reasons why people get a rash on their hands after washing. The first one, and the more rare one, is allergy. If your skin gets red, itchy, or a rash appears after using soap and water, you might be allergic to some of the ingredients in the hand wash. If you are allergic to an ingredient, you will always get a reaction from a contact with it, even if the concentration is very low.
The second, and more widespread reason for getting a hand rash from washing is irritation. Unlike allergy, irritation is not always connected to one ingredient. A combination of different factors usually triggers an irritation. A major factor in developing an irritation is weak skin barrier. The same ingredients that make hand washing work against bacteria and viruses - so called surfactants, or detergents (including soap) - interfere with lipids in the skin's natural protective top layer, weakening the skin's defenses against potential irritants. Because of the weakened barrier, the skin is more likely to develop a reaction to fragrances, plant extracts, preservatives, and other ingredients in hand washes and hand creams. It is possible that, at one time, the skin reacts with a violent irritation, for example, to a hand soap fragrance. Once the skin barrier heals though, the same person can tolerate the same fragrance without a problem.
The trouble is that for the most part, skin allergy and irritation can look and feel the same. What do you need to do in practice if you have a rash from hand washing, and are not sure whether it is an irritation or allergy?
Skincare industry is full of overblown marketing promises. There are lots of products on the market that are outright harmful to your skin. To figure out what's good and what's not, it is definitely helpful to know a little bit about the science of skincare.
The word "science" sounds intimidating to many of us. What it means though, in a nutshell, is that we test if something is true, instead of assuming or believing it is. This is why science-based skincare follows evidence. Take an anti-aging serum. If you are following a science-based approach to skincare, you will ask two questions. The first one is: "Did someone test this product and was able to confirm that it reduces wrinkles in real people?". The second question comes if there is no positive answer to the first one. This question is: "Did someone test the main ingredients in this product and was able to confirm that they reduce wrinkles in real people?".
You do not need to have a PhD to adopt science-based skincare. You need to follow a few simple principles.
If you are interested in skincare, and especially if your skin is acne-prone, you probably have heard that some ingredients are considered comedogenic. People believe that skincare products containing these comedogenic ingredients “break them out” or, in other words, cause acne spots and comedones (blackheads and whiteheads). Many consumers go to great lengths to check the ingredient lists of the products they use against comedogenicity ratings to make sure that their skincare does not contain the “offenders”.
In reality, ingredient comedogenicity ratings tell us little about the actual potential of a product to cause or aggravate acne. Here is why.
First of all, when people say that a product “breaks them out” they usually mean that they notice pimples a day or two after using it. This is simply not enough time for comedones to form (it takes over two weeks). If a product “breaks you out”, it is most likely due to the irritant reaction in your skin rather than the product “clogging pores”. An ingredient and a product can be irritating (and therefore lead to breakouts) but not comedogenic. And the opposite is true: a product or an ingredient can be comedogenic without being a high-risk irritant.
In addition to photo-aging (sun damage) and intrinsic skin aging (changes in the skin cell functioning as the organism’s age increases) that hits both male and female sexes, women also experience a so called “hormonal aging” that comes with menopause.
Changes in the female body that lead to menopause also lead to a permanent decline in production of a number of hormones, including estrogen and testosterone. These hormones regulate the skin functioning. Reduced estrogen level, in particular, leads to a sharp decrease in collagen content, skin elasticity, thickness and moisture levels, as well as worsening of the wound healing capacity. About 30% of collagen content in skin can be lost within the first 5 years following the menopause.
Reduced water content in the menopausal skin means that the skin barrier can become weaker. As a result, the skin can suddenly become more sensitive and reactive. Acne spots can also appear because of the hormonal changes.
Sensitive skin is not a skin type but rather a symptom of a weakened skin barrier function. Skin behaves as sensitive (with dryness, tightness, itchiness, redness, frequent inflamed breakouts) when the balance in the upper layer of the skin is disturbed, and the skin struggles to protect itself from external “aggressors” (for example, irritating ingredients, pollutants, allergens, weather conditions) and from evaporating too much water.
There are multiple possible causes of sensitive skin. It makes sense to split them into “external” (relating to all things the skin comes in touch on the outside) and “internal” factors (genetic conditions and things that “touch” the skin from within the body like medicine or food).
Sensitive skin is prone to irritant and allergic reactions. Dryness, breakouts, dull complexion, tightness, peeling, redness, and even excessive oiliness at times can all be signs of sensitive, reactive or “intolerant” skin. Dermatologists strongly recommend treating acne-prone skin as sensitive skin.
It is more accurate to refer to sensitive, or reactive skin as a skin condition rather than a skin type. Our skin becomes sensitive when the natural skin barrier is compromised. In the majority of cases, the skin barrier becomes compromised because of the external environment (for example, dry heated air, cold temperatures, wind) and substances we expose our skin to (cosmetics and cleaning products). Once we remove the “offending” factors (for example, use a humidifier in a room, start using protective gloves when cleaning the house, and/or stop over-washing, over-exfoliating our skin, or remove irritating ingredients from our skincare routines), the skin barrier starts healing and usually returns to normal within a couple of weeks.
In some cases, skin sensitivity is caused by an internal factor (for example, genetics) that leads to an abnormality in the skin barrier function, in other words, skin sensitivity can be caused by a chronic medical skin condition such as atopic dermatitis (eczema), psoriasis or rosacea. If your skin sensitivity is severe (the skin shows signs of irritation frequently, even if you remove most potential external “offenders” such as harsh cleansers, exfoliators, essential oils and perfumed cosmetics), it is best to seek a consultation with a dermatologist to identify the cause of the reactivity and work out a skincare regimen that suits your skin. Even if your skin sensitivity is caused by an internal medical condition, a gentle minimalist skincare routine can help you support your skin barrier and minimize unwanted symptoms.
Azelaic acid is present in our skin naturally: it is produced by normal skin’s microbiome. In skincare, it is an effective and relatively gentle ingredient that helps reduce hyperpigmentation, calm down inflammation and can help neutralize free radicals. It is successfully used for treatment of acne, melasma, and rosacea. It has a mild exfoliating effect. It might also be able to help regulate sebum production in skin and help speed up the skin cell turnover.
Azelaic acid does not absorb UV and visible light, meaning that it is highly unlikely to cause sun sensitivity (in other words, a photoirritative or photosensitive reaction). At the same time, there are rare reports of photosensitivity when using topical medications (creams, gels) with azelaic acid. It is possible that these reactions are caused by other ingredients in the formula.
While azelaic acid is highly unlikely to lead to sun sensitivity, it is still a good idea to be extra cautious when it comes to sun exposure if you are using azelaic acid. The main reason is that if you are using azelaic acid, you are probably concerned with hyperpigmentation and/or acne, blackheads and clogged pores. Sun is not your skin’s friend in these conditions, and you need to limit the UV exposure as much as possible. This is why it is a great idea to wear a broad spectrum sunscreen with high SPF daily, avoid direct sun and wear sun-protective hat and clothing if you are using azelaic acid. If you want to be extra-cautious, you might prefer to use products with azelaic acid at night. It is not strictly necessary, especially if you are not going to spend your day in a direct sunlight, but many people prefer doing it anyway because the texture of products with azelaic acid does not always work great under sunscreens and makeup.
Oleanolic acid is an antioxidant (triterpenoid) that can be extracted from many plants, for example from olive oil, apples, and garlic. Early research shows that oleanolic acid has a potential to influence different processes within the skin, even though most of the research has been done in vitro (in a petri dish) or using animals. For example, the research has shown that oleanolic acid might reduce scarring because it reduces the overproduction of collagen type I and III in wounded skin. There is also preliminary evidence that oleanolic acid might work against acne because it can block the synthesis of a specific form of testosterone in skin that triggers an increase in sebum production. Oleanolic acid might also be able to improve the skin barrier function and reduce inflammation, and has a promise in treating atopic dermatitis and helping sensitive skin types. While all this research is promising, there is too little data on how oleanolic acid works in human skin to confirm if it is indeed effective, in what concentrations, and if there are adverse effects.
Check out skincare products with oleanolic acid here .
Should you avoid SLS in your cosmetics if you have sensitive skin? This question has spurred quite some debates in skintellectual circles recently. The line of debate primarily lies between dermatologists and cosmetic formulators. Dermatologists (including our advisor Dr. Sandy Skotnicki) have been advising for a while to avoid SLS-containing products if you have a sensitive, reactive skin. Cosmetic chemists, on the other hand, insist that products with SLS can be formulated to be non-irritating. Here are our thoughts on the matter.
SLS is the industry standard skin irritant. It is the go-to irritant researchers use as a control group for skin irritation studies. It is also used to evaluate the sensitivity and accuracy of different methods used to detect irritant skin response. For example, in this in-vivo study , different patch test systems were evaluated for detection of irritant skin reaction to water, 0.06% concentration of SLS, and two cosmetic products. The choice of the patch test system mattered: while the first one tested did not show a meaningful difference between the skin reactions to water and 0.06% SLS, the second one detected the stronger reaction to the SLS.
What does it mean for us, consumers? We think that in the case of the SLS debate, it is more prudent to follow the advice of the dermatologists and err on the side of caution - that is avoiding SLS in your products if your skin is sensitive. We have data to confirm that SLS is irritating to the skin even in small concentration, even though not all test methods used can detect it. Besides that, most cosmetic products are not tested using the cumulative irritancy testing - so we are not sure what data do cosmetic formulators have to show that their SLS-containing products are indeed less irritating than, let's say, the 0.06% SLS emulsion used to induce skin irritation in the study cited above.
The diagnosed incidence of cosmetics-related skin reactions in North America has increased by 2.7 times in North America over the decade between 1996 and 2006, finds a study recently published in the Journal of the American Academy of Dermatology. This study did not include irritant and allergic reactions to sunscreens.
In 1996-1998, out of people referred to patch testing, 22% of females and 17% of males had an irritant or allergic reaction to cosmetic ingredients. These numbers more than doubled in 10 years, when 49% of females and 49% of males tested had a positive patch reaction to cosmetic ingredients.
Other data from Europe confirms the trend A Danish study found that contact sensitization to cosmetic allergens doubled from 1990 to 1998. In a 2013 survey, European dermatologists noted a 5-year increase in males reporting sensitive facial skin.