Bible of Acids: Antioxidants
Part 2 of our Bible of Acids series focuses on antioxidants. Antioxidants are compounds that inhibit the oxidation of molecules in the body.
*Geek break: Oxidation is the process in which a chemical substance changes because of the addition of oxygen. Carbon dioxide is a necessary result of the oxidation of carbon compounds. You are a carbon-based life form! When we inhale oxygen we exhale carbon dioxide. The shift in balance between "oxidants" and antioxidants is called oxidative stress.
Now back to our regularly scheduled program. Antioxidants are man-made or natural substances that may prevent or delay some types of cell damage. The human body naturally produces free radicals and the antioxidants to counteract their damaging effects. Free radicals are highly unstable molecules that are naturally formed when you exercise and when your body converts food into energy. Your body can also be exposed to free radicals from a variety of environmental sources, such as cigarette smoke, air pollution, and sunlight. Free radicals can cause “oxidative stress,” a process that can trigger cell damage. Free radicals often outnumber the amount of antioxidants naturally produced. Therefore, the body needs a constant supply of external sources of antioxidants to counter the effects of free radicals.
You can and should combat free radicals on two fronts: internally and externally. Antioxidants are found in many foods, including fruits and vegetables. A well balanced diet will ensure that you are helping your body produce antioxidants. There are also antioxidant supplements. However, these have not been proven to be as effective as consuming antioxidant rich foods. Many modern cosmetics include antioxidant rich ingredients derived from the same fruits and vegetables you should be eating to fight free radicals. These ingredients often work synergistically with AHAs and BHAs to protect the outer layer of the skin.
* The antioxidants mentioned below can be used by all skin types as the serum step of your skincare routine. However, do note the caveats discussed in the Vitamin C section.
Ellagic acid is a natural phenol antioxidant extracted from oak galls and various fruits and nuts; especially walnuts, pecans, raspberries, and pomegranates. It reduces the signs of sun damage and prevents brown spots from forming. Ellagic acid can help protect skin from oxidative stress induced by UV radiation and the natural aging process. This may be due to ellagic acid’s ability to repress the effects of intercellular adhesion molecule (ICAM), a compound involved in the inflammatory response. Ellagic acid also inhibits matrix metalloproteinase (MMP), an enzyme that signals collagen breakdown (i.e. aging skin). Together, these properties encourage the maintenance and/or improvement of the skin’s elasticity, which may result in the diminishing of fine lines and wrinkles. As a tyrosinase inhibitor, ellagic acid is also an effective skin brightener and safer alternative to hydroquinone. In plants, ellagic acid provides natural UV protection as well as defense against bacterial and fungal pathogens.The same protective properties that ellagic acid provides in plants are believed to occur in humans. It also has some ability to inhibit blood flow and retard the growth of cancer cells.
Plant-based, phenolic antioxidant found naturally in the seeds of fruits like apples and oranges, as well as some vegetables, and grains like rice and bran. It fights free radicals and helps skin protect against further sun damage. It reduces wrinkles, dark spots, uneven skin, and signs of photoaging. When applied topically it enhances the stability of antioxidant vitamins C and E. There’s an eight-fold increase in photoprotection (UV protection) when ferulic acid is added to vitamins C and E! In fact, you can now find serums that do the job of combining ferulic acid with vitamins C and E for you. However, they can be quite pricey!
Hyaluronic acid is a naturally occurring humectant widely distributed throughout your connective, epithelial, and neural tissues. It's primary benefit is it's capacity to attract and hold large amounts of water. One of molecule of hyaluronic acid can hold 1,000 times its weight in moisture! The average 70 kg (154 lb) person has roughly 15 grams of hyaluronic acid in the body, one-third of which is turned over (degraded and synthesized) every day. As we age we lose the ability to retain moisture, resulting in loss of firmness, pliability, and plumpness. Topical application of hyaluronic acid replenishes moisture, reducing the appearance of fine lines by plumping the outer most layer of the skin. Moisture balance is particularly important for oily acneic skin because if hyaluronic acid can keep the moisture levels balanced the skin will not need to overproduce oil that can clog your pores. Balance, for oily skin doesn't mean perfectly matte without any oil. You need the oil your skin produces to help lock in the moisture attracted by the hyaluronic acid. Lastly, hyaluronic acid is a powerful antioxidant defense against UV radiation tissue damage. Think about it, water reflects light. If you have a healthy moisture barrier in the outermost layer of your skin then the UV rays are being reflected away from your body. Now to be clear, this isn't nearly enough to prevent sun damage. Water reflects less than 10% of incident UV radiation. This is partly why it is so easy to get burned at the beach. If you are in the ocean and the light is being reflected off of the water then your UV exposure increases. You must wear sunscreen!
Hyaluronic Acid vs. Sodium Hyaluronate: You might have seen sodium hyaluronate in some of your skincare products and wondered about it's relationship to hyaluronic acid. It is in fact a derivative of hyaluronic acid that has all the same benefits but is more easily absorbed by the skin. For maximum impact you would want a product that has both hyaluronic acid and sodium hyaluronate.
Hyaluronic Acid and Cancer: Hyaluronic acid also plays a significant role in cell proliferation and migration. As such, it is believed to contribute to the progression of malignant tumors. To be clear, hyaluronic acid does not give you cancer! It is not a carcinogen. However, in some cancers, hyaluronic acid levels do correlate with malignancy and an adverse diagnosis. Therefore, it is often used as a tumor marker for prostate and breast cancer and can be used to monitor the progression of disease.
L-ascorbic Acid (Vitamin C)
Vitamin C, also known as ascorbic acid and L-ascorbic acid, is a vitamin found in food. The “L” in front of Ascorbic is a reference to how the molecule itself rotates to light and refers to its source. L-Ascorbic Acid comes from fruits and vegetables such as: oranges, green peppers, watermelon, grapefruit, kiwi, mango,broccoli, raw and cooked leafy vegetables, winter squash, and berries. Vitamin C should be consumed and applied topically. Five to nine servings of fruits and vegetables should give you your daily recommended dose. However, it is important to remember that vitamin C is subject to change when exposed to light, air and heat. When our vitamin C-packed foods are cooked, they lose some (and sometimes more than some) of their vitamin C power. Additionally, a study published in 2004 in the Journal of American College of Nutrition found declines in the amount of protein, calcium, phosphorus, iron, riboflavin (vitamin B2), and vitamin C over the past half century. Basically, today’s fruits and vegetables were found to contain 30% less vitamin C than that of your grandparents’ fruits and vegetables!
Don't dismay because your skin can still benefit from the topical application of vitamin C derived from these fruits and vegetables. Vitamin C is a potent antioxidant that fights free radical damage, lightens dark spots and hyperpigmentation, and rebuilds collagen. The higher the concentration of L-ascorbic acid the more potent and effective. We suggest that beginners start with serums that have a low concentration of L-ascorbic acid and work your way up. L-Ascorbic Acid found in topical skincare products carries a concentration between 5 percent to 20 percent. A higher concentration can irritate the skin. People with rosacea and sensitive skin conditions might need to avoid products with Vitamin C as it may cause irritation. Oily, dry and combination skin types can benefit greatly from L-Ascorbic Acid products. Note that for those with chronic acne, L-ascorbic acid can cause purging or a temporary increase in acne as your skin adjust to the product. This depends on the concentration and of course each person is different. There are some acne-prone people who do not experience purging.
As mentioned above, vitamin C is particularly vulnerable to light and air and must be packaged to protect it from these elements during routine use. Repeated exposure to light and or air greatly diminishes it's effectiveness. You can tell when your vitamin C is no longer effective because the oxidization process will turn your serum a copper or brownish color.
*Pro tip: Test your Vitamin C serum on a white index card as soon as you buy it to see if it has already begun to turn and if all is well periodically retest it.
Application: Opinions do vary regarding when to use Vitamin C in your skincare routine. For example, someone with sensitive skin might choose to use it after a light toner. You hear the term "serum" and assume that it should be used during the traditional serum step (post toner and essence). However, we recommend using it right after cleansing (i.e. before applying toner). This ensures that the vitamin C's potency is not diluted by other products (especially water-based products) and is allowed to fully penetrate the outer layer of skin.
Vitamin C Serums Are Not Created Equal: There are many formulations of "Vitamin C" serums on the market. In our discussion above we are referencing the true L-ascorbic acid derived from fruits and vegetables. Some serums are made of pure L-ascorbic acid but some are made of derivatives of L-ascorbic acid. Some serums are water-based and some are waterless. As we mentioned above, L-ascorbic acid is sensitive to air and light, which means it is difficult to stabilize and many serums with L-ascorbic acid have a very short shelf life. Therefore, derivatives were developed to "solve" that issue. They are more stable (i.e. last longer) than pure L-ascorbic acid. Your body naturally converts the derivatives into L-ascorbic acid. If you want to know more about the formulations of L-ascorbic acid derivatives checkout this video above from one of our favorite skincare youtubers @Gothamista. She is a great researcher!
Even among serums with pure L-ascorbic acid the formulations still fall into two categories: water-based and waterless. While the water-based formulations aren't as stable as the non-water-based serums, they are less irritating. Vitamin C is water-soluble, meaning it dissolves in water. Below are some of our favorite serums with L-ascorbic acid and or an L-ascorbic acid derivative.
Vitamin C and Niacinimide: In our research we found that there is some concern that vitamin C and niacinamide (to be discussed in part 3) interact negatively or cancel each other out when applied together. Not sure where that rumor came from but it isn't true. This combo is actually really great for oily and acne-prone skin types. It also has great anti-aging properties. So don't be afraid to pair these two powerhouse acids!
That's all folks! Well, for part 2.
We hope you take full advantage of the power of antioxidants; both in your diet and your skincare. Tune in again this Friday for the final installation of our Bible of Acids series that will focus on anti-acneic and anti-aging acids. You might be particularly interested in learning more about plant based retinol Bakuchiol.
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