{"id":252,"date":"2021-03-17T10:30:00","date_gmt":"2021-03-17T10:30:00","guid":{"rendered":"https:\/\/wellconnected.murad.com\/?p=252"},"modified":"2025-06-25T16:30:57","modified_gmt":"2025-06-25T23:30:57","slug":"sniff-tests-and-product-cocktails-what-experts-are-not-telling-you-about-vitamin-c-and-your-skin","status":"publish","type":"post","link":"https:\/\/wellconnected.murad.com\/sniff-tests-and-product-cocktails-what-experts-are-not-telling-you-about-vitamin-c-and-your-skin\/","title":{"rendered":"Sniff tests and product cocktails: What experts are *not* telling you about vitamin C and your skin"},"content":{"rendered":"\n

When it\u2019s time for glowing skin, derms agree it\u2019s time for vitamin C<\/a>. What we always hear about vitamin C: It\u2019s a clinically proven skincare powerhouse that helps brighten dark spots and boost radiance. But facts like potency, percentages and how it plays with other ingredients are still cloudy sometimes. We asked Dr. Corey L. Hartman\u2014assistant clinical professor of dermatology at University of Alabama and founder of Skin Wellness Dermatology\u2014to shine light on what we usually don\u2019t hear about this perennially popular ingredient.<\/p>\n\n\n\n

It should pass the sniff test<\/h3>\n\n\n\n

Vitamin C is notoriously prone to \u201coxidizing,\u201d or losing efficacy. Like how a sliced apple turns brown, vitamin C \u201ccan break down when it\u2019s exposed to light or air,\u201d Dr. Hartman explains. \u201cAlways check expiration dates on products. If you notice a sour smell or discoloration, it\u2019s most likely breaking down.\u201d<\/p>\n\n\n\n

It\u2019s preventative<\/h3>\n\n\n\n

\u201cCollagen production peaks at age 22 and decreases every decade thereafter,\u201d Dr. Hartman notes. Free radicals (oxidants from UV light and pollution) are one of the biggest contributors to collagen loss. Antioxidants like vitamin C<\/a> diffuse free radicals to prevent skin damage, thereby helping healthy collagen stay intact to prevent sagging and sallow skin.<\/p>\n\n\n\n

It\u2019s not the form, but how much<\/h3>\n\n\n\n

Vitamin C by any other name\u2014like ascorbic acid, ascorbate, etc.\u2014is still always l-ascorbic acid. That\u2019s why Dr. Hartman advises looking at the percentage in products, whenever possible. Based on his experience, \u201cthe ideal concentration of vitamin C in a topical form is 20%.\u201d<\/p>\n\n\n\n

It has friends in the business<\/h3>\n\n\n\n

Love to \u201ccocktail\u201d your skincare? Vitamin C plays well with other antioxidants like vitamin E (tocopherol) and ferulic acid. \u201cTogether, they have optimal absorption benefits when it comes to anti-aging, skin brightening and protection against free radical damage,\u201d Dr. Hartman says. \u201cIt also plays well with vitamin B and hyaluronic acid<\/a>.\u201d On the other hand, he points out that pH levels in retinol and niacinamide may cause incompatibility with vitamin C.<\/p>\n\n\n\n

It\u2019s worth noting, however, that dermatologists often take different stances on how vitamin C mixes with other ingredients, so if you can\u2019t bear the thought of giving up your retinol<\/a> or niacinamide<\/a>, try applying them at night and vitamin C<\/a> in the morning. If you want to use them at the same time, Hartman recommends waiting a half-hour between applications.<\/p>\n\n\n\n

It works best in leave-on treatments<\/h3>\n\n\n\n

\u201cVitamin C is best delivered to the skin via a serum<\/a> due to its thinner vehicle, and its ability to be readily absorbed into the skin,\u201d Dr. Hartman explains. \u201c[Leave-on treatments] are also meant for long-term exposure to skin and maximum absorption [in contrast to cleansers that rinse away].\u201d Vitamin C has also been shown to enhance SPF\u2019s skin-protecting benefits.<\/p>\n\n\n\n

It should be eaten, too, for optimal benefits<\/h3>\n\n\n\n

\u201cVitamin C isn\u2019t produced by the body,\u201d Dr. Hartman notes. Thus, we need to consume nutrient-rich foods and supplements to compensate. Citrus fruits are famously rich in the vitamin C, but kakadu plums, guavas, sweet yellow peppers and (gram-for-gram) thyme actually pack even more.<\/p>\n","protected":false},"excerpt":{"rendered":"

When it\u2019s time for glowing skin, derms agree it\u2019s time for vitamin C. What we always hear about vitamin C: It\u2019s a clinically proven skincare powerhouse that helps brighten dark spots and boost radiance. But facts like potency, percentages and how it plays with other ingredients are still cloudy sometimes. We asked Dr. Corey L. Hartman\u2014assistant […]<\/p>\n","protected":false},"author":21,"featured_media":257,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-252","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-skin"],"metadata":{"_edit_lock":["1750894259:21"],"_edit_last":["21"],"primary_category":["5"],"_primary_category":["field_608c33bdd26d5"],"show_featured_image":["1"],"_show_featured_image":["field_609ee1cf1ce13"],"post_views_count":["5835"],"_thumbnail_id":["257"],"adobe_analytics_repeatable":["a:1:{i:0;a:2:{s:4:\"name\";s:0:\"\";s:5:\"value\";s:0:\"\";}}"],"_wp_old_date":["2021-05-17","2021-06-08"],"mobile_image":[""],"_mobile_image":["field_60bf7692abe28"],"_post_views_count":["field_6107dfafd6a27"],"sidebar_products_use_global_default":["0"],"_sidebar_products_use_global_default":["field_63a349a11086a"],"sidebar_products_title":["Related Products"],"_sidebar_products_title":["field_6408d62123449"],"sidebar_products_items":[""],"_sidebar_products_items":["field_63a349a110878"],"sidebar_products":[""],"_sidebar_products":["field_63a349a0dadad"],"_yoast_wpseo_primary_category":["5"],"_yoast_wpseo_content_score":["60"],"_yoast_wpseo_estimated-reading-time-minutes":["3"],"_yoast_wpseo_title":["Everything you need to know about vitamin C | Murad Skincare"],"_yoast_wpseo_metadesc":["Vitamin C skincare secrets experts won't tell you. Sniff tests, product cocktails, and maximizing vitamin C benefits."]},"aioseo_notices":[],"acf":{"primary_category":{"term_id":5,"name":"Skin","slug":"skin","term_group":0,"term_taxonomy_id":5,"taxonomy":"category","description":"","parent":0,"count":238,"filter":"raw"},"show_featured_image":true,"post_views_count":"5835","mobile_image":false,"sidebar_products":{"use_global_default":false,"title":"Related Products","items":""}},"_links":{"self":[{"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/posts\/252","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/users\/21"}],"replies":[{"embeddable":true,"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/comments?post=252"}],"version-history":[{"count":6,"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/posts\/252\/revisions"}],"predecessor-version":[{"id":13517,"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/posts\/252\/revisions\/13517"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/media\/257"}],"wp:attachment":[{"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/media?parent=252"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/categories?post=252"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wellconnected.murad.com\/api\/wp\/v2\/tags?post=252"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}