“Looking good doesn’t affect your success” is one of those pernicious anti-advices like “elite university degrees don’t matter” and “family connections are worthless in our meritocratic society.”

Let's not engage in quakery and resort to knowledge instead.

Oral and transdermal (topical) application of Vitamin C (and other molecules in general) follow completely different routes with different absorption rates and accompanying nuances.

Oral intake. Absorption rate is dosage dependent:

  – At moderate doses (≤ 250 mg/day): 70–90 per cent of ascorbate is absorbed into the bloodstream. Bloodstream means just that – Vitamin C will be distributed throughout the entire body, which includes tissues, internal organs and skin. Active absorption takes place in the small intestine predominantly by SVCT1 and SVCT2 sodium-ascorbate co-transporters.

  – At high doses (≥ 1g a day): passive diffusion takes over and also takes place in the small intestine although now via GLUT transporters that become saturated and absorption efficiency drops to 50 per cent or lower.

The half-life of Vitamin C taken orally is approximately four hours anyway, after which any excess of it still circulating will be rapidly excreted via the renal route (kidneys). Studies report that significantly less than 0.1 per cent makes into the epidermal (skin) layer.

Transdermal (topical) application. Depends on the concentration and several factors, but a 20% concentration serum (not a cream) can achieve a > 80% absorption rate through the skin into receptor fluid after 24 hours. Half-life of Vitamin C applied topically is approximately 4 days.

Recap: less than < 0.1 % / 4 hours half-life for the oral route vs more than 80 % / 4 days half-life for the transdermal route.

  L-ascorbic acid must be formulated at pH levels less than 3.5 to enter the skin. Maximal concentration for optimal percutaneous absorption was 20%. Tissue levels were saturated after three daily applications; the half-life of tissue disappearance was about 4 days. Derivatives of ascorbic acid including magnesium ascorbyl phosphate, ascorbyl-6-palmitate, and dehydroascorbic acid did not increase skin levels of L-ascorbic acid.

Red light, or something more chemical?

I know this was a joke, but I can't really understand the worldview that says people should accept physical decline in a passive way. The fact is, we actually have a lot of control over how quickly and how well we age. Just using sunscreen can prevent a lot of the age-related loss of skin structure. And interventions like topical retinoids or collagen induction (e.g. microneedling) can even restore some thickness and elasticity that have already been lost. This also goes for fitness, joint health, and a lot of other things. Caring for your body is actually well aligned with the goals of psychotherapy.

This is a weird video to see after one of my son's doctors told me I should supplement him with zinc. Of course I'm following dosage recommendations.

The effects can be significant, even if not due to vit C but something else in the oranges.