Every day your skin faces a barrage of assaults: UV radiation, 污染, 其他环境毒素(如.g. fragrances, many other synthetic inactive ingredients in your cosmetics). 抗氧化剂 就像 维生素C help to fight off free radicals and the damage they wreak on your skin. 但并不是所有的维生素C配方都是一样的. What skin care benefits you can reap from 维生素C depends on how well your skin can absorb it.
On the Level: 维生素C Absorption through the Epidermis
的主要方法 维生素C 通过饮食摄入来吸收. 维生素C is readily absorbed through the intestine wall and transported throughout the body. The foods you eat determine your plasma 维生素C levels, which play an important role in many metabolic functions. 然而, the skin health benefits 维生素C provides are not always fully realized just because you have sufficient plasma 维生素C levels. 为了获得最大的利益, you need to deliver 维生素C directly to your skin, which is possible through topical applications—skin creams, 乳液, 血清, 等.
作为水溶性维生素之一, 维生素C is a small enough molecule that it can readily pass (diffuse) through cell membranes to be absorbed through the epidermis and transported to the underlying dermis where it can directly fight oxidative stress that leads to wrinkling, hyperpigmentation and development of skin cancers. 然而, 维生素C absorption through the skin greatly depends on the pH of the 维生素C application. Because the skin is slightly acidic, so, too, must the 维生素C delivery system be acidic. pH值低于4.0是理想的. The concentration of 维生素C also impacts absorption. You don’t necessarily absorb more 维生素C just because a product has a higher concentration of 维生素C in it. Maximum absorption seems to happen with 20% 维生素C. Higher concentrations will 就像ly lead to excess 维生素C being transported from the tissues into the blood where it will eventually be filtered out and excreted in urine.
One major challenge to topical delivery is getting 维生素C to live cells beneath the (dead) stratum corneum. The key to effective topical delivery of 维生素C is exfoliation—removing the uppermost layer of dead cells allows 维生素C formulas to be applied directly to live cells. 化学换肤, microderm abrasion and other gentle mechanical exfoliants will all work.
Dose and Delivery: 维生素C衍生物s and Chemical Stability
Once you have cleared the way for effective topical 维生素C delivery, you want to make sure that the 维生素C you apply to your skin will be effective. Effectiveness depends on two factors: the potency of the 维生素C derivative used in your skin care formula and its chemical stability.
维生素C的最纯形式, 天然的生物可利用性, ready to fight oxidative stress on the cellular level is L-Ascorbic酸. There are a number of other derivatives of 维生素C, which can do all the things pure 维生素C can do…后 they are converted to L-Ascorbic酸 in the body. 然而, the chemical conversion of these other derivatives ultimately means that measure for measure, these derivatives deliver less bio-available 维生素C to your cells.
The chart below summarizes the 维生素C derivatives commonly found in skin care products and their potency:
|
维生素C衍生物
|
效力
|
| L-Ascorbic酸 |
100% |
| 抗坏血酸钠 |
95% |
| 磷酸抗坏血酸镁 |
60% |
| 抗坏血酸磷酸钠 |
55% |
| Ascorbyl棕榈酸酯 |
40% |
| Tetrahexyldecyl抗坏血酸盐 |
13% |
The potency refers to the amount of 维生素C that is actually delivered to your cells. 在一克l -抗坏血酸中, one gram of 维生素C is delivered to your cells, 而是一克抗坏血酸磷酸钠, 例如, just over ½ a gram of 维生素C is delivered to your cells. That means that when skin care products use derivatives of L-Ascorbic酸, they must use a lot of the compound to deliver a sufficient amount of 维生素C that can actually help combat the signs of oxidative stress.
不管维生素C的效力如何, whether or not it will be effective on your skin depends on its chemical stability in the skin care formula. 维生素C will begin to neutralize free radicals anywhere, even in the formula that makes up its delivery vehicle to your skin—i.e. 你乳液或精华液里的其他东西. Free radicals may be introduced to the delivery compound because of natural degradation caused by heat, 光或空气暴露. 如果你的维生素C护肤品是棕色的, its antioxidant properties have already spent; it will not do any good on your skin.
稳定维生素C (i.e. suspend its antioxidant activity until it gets absorbed by your skin), 它必须仔细加工和储存. Formulations that compound 维生素C with another antioxidant, 比如维生素E, 有效地保持维生素C的稳定性. (Research also shows that Vitamin E boosts the effectiveness of 维生素C and vice versa.)
太阳集团娱乐场登陆网站品’ Commitment to Pure 维生素C
所有 维生素C新太阳集团娱乐app 所产生的 太阳集团娱乐场登陆网站品 只含有100%纯l -抗坏血酸. So, ounce per ounce, they deliver the most potent form of 维生素C to your cells. We also use cold water processing to preserve the chemical stability of the L-Ascorbic酸, and our formulas capitalize on the antioxidant synergy of 维生素C and Vitamin E.
