Vitamin C and Skin
Last week we learned about oxidative damage and its negative impact on the skin. In short, exposure to things like UV radiation from the sun and other toxins, like from smoking, causes free radicals in the skin and when production exceeds our natural antioxidant defenses, damage occurs. The skin is on the forefront of our defense and comes in more contact with the outside world than any other organ; the skin therefore, is where the first signs of aging occur.
Enter vitamin C. Vitamin C is a showstopper! It’s a potent water soluble vitamin and antioxidant that helps our body defend against oxidative damage. Vitamin C can be found throughout the skin and it supports functions like stimulating collagen and protecting against UV-induced photodamage. The most compelling argument for the role of vitamin C in skin health comes from the observation that deficiency causes obvious skin problems - early signs of scurvy (ie vitamin C deficiency) for example include fragile skin and poor wound healing. Vitamin C may provide significant protection against the changes that happen to skin over time (1).
When your blood levels are low, some vitamin C can be delivered through topical application, however this is dependent on the product’s formulation. It is only when the pH is below 4 and the vitamin C is present as ascorbic acid, that some penetration occurs (1). The science behind absorption is beyond the scope of this writing, however it’s important to note that if you have adequate vitamin C levels in your blood, topical application of vitamin C does not appear to increase levels in the skin.
So this means that before we all go buy vitamin C serums in the hopes of preventing collagen loss and less oxidative damage, let’s make sure we are getting enough vitamin C in the diet. This is an ESSENTIAL vitamin, meaning that we have to get it from the diet and when there are adequate levels in the blood, there are adequate levels in the skin (1).
Vitamin C can be found in supplement form, as well as in a number of fruits and vegetables - including oranges, cantaloupe, watercress, bell peppers, strawberries, and broccoli. Getting enough of these fresh foods is vital for collagen synthesis and to combat free radical effects (2).
The current recommendation for daily intake of vitamin C is 90 mg/day for adults. Smoker’s should add an additional 35 mg/day (for a total of 125 mg/day) because smoking is associated with low vitamin C status (3). Some literature suggests that 90 mg/day is not enough and should be increased to 200 mg/day for optimal intake and to maximize the vitamin’s potential (3).
List of Foods and their Vitamin C Content (4).
Kiwi - 1 fruit - 131 mg
Grapefruit juice - ¾ cup - 94 mg
Orange Juice, raw - ¾ cup - 93 mg
Strawberries - 1 cup - 85
Orange - 1 med - 65 mg
Sweet red pepper, raw - 1 med - 65 mg
Broccoli, cooked - ½ cup - 51 mg
Grapefruit, raw - ½ med - 44 mg
Brussels sprouts, cooked - ½ cup - 37 mg
White potato with skin - 1 med baked - 22 mg
Red ripe tomato - 1 med raw - 17 mg
Raw Banana - 1 med - 10 mg
Apple raw - 1 med - 8 mg
Spinach raw - 1 cup - 8 mg
In addition to increasing your dietary intake, it is reasonable to consider supplementation. There are many options out there such as capsules powders and you can find vitamin C at most grocers. The upper limit of supplementation is 2 grams per day to avoid digestive upset (3). Consult your physician regarding supplementation if you tend towards kidney stones. You can also purchase vitamin C through my online pharmacy where you get 10% off. I’ve been using Metabolic Maintenance Vitamin C Powder for the past month.
Thanks for reading.
Resources
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579659/