Vitamin C and Climate

 The evolutionary history of humans regarding vitamin C production and its implications for health, particularly in the context of changing climates and nutritional needs. It argues that the loss of vitamin C production in human ancestors is intricately linked to historical climate shifts and how this has impacted human health over millions of years.

1. Evolution and Vitamin C Production:

• Early human ancestors lost the ability to produce vitamin C around 40 to 60 million years ago, during a warmer period filled with abundant fruit.

• Producing vitamin C requires energy and liver resources, providing an evolutionary advantage to species that obtain it from their diet instead.

2. Impact of Climate Change:

• As Antarctica drifted to the South Pole and the climate became colder and drier, the availability of vitamin C-rich fruits decreased.

• Therefore, humans now live with a chronic deficiency in vitamin C, which impacts health across varying climates.

3. Vitamin C Needs and Deficiencies:

• Most mammals require about 20 mg of vitamin C per kilogram of body weight daily; for an average human, this translates to around 1.4 grams.

• The recommended dietary allowance (RDA) in some regions is much lower, leading to potential deficiencies in the general population.

4. Vitamin C and Health:

• Vitamin C plays crucial roles in collagen synthesis, immune function, and protection against oxidative stress.

• During infections, vitamin C levels drop significantly in humans, heightening risks like capillary leaks and oxidative damage compared to other mammals.

5. Responses to Stress:

• Many animals can increase vitamin C production significantly when stressed or infected, unlike humans who rely on dietary intake.

• Vitamin C's role as an antioxidant is powerful during infections; low levels can impair the immune system’s ability to respond effectively.

6. Vitamin C and Viral Infections:

• Vitamin C enhances interferon production necessary to manage viral replication.

• It helps stabilize iron in the body, impacting the availability of iron for viruses to use in replication.

7. Vitamin C in Cancer Treatment:

• High doses of vitamin C, especially by intravenous delivery, demonstrate potential in aiding cancer treatment by increasing oxidative stress in cancer cells.

• Early therapeutic doses are kept cautious to manage the necrotic response of dying cancer cells.

8. Synergistic Nutritional Roles:

• Vitamin C, vitamin D, and zinc work together to combat viral infections, with each having unique roles in immune response.

• Vitamin C acts fast, vitamin D has a longer-term regulatory role, and zinc is essential for antiviral enzyme function.

The history of vitamin C production in humans highlights the evolutionary trade-offs made during a warmer climate. As climates shifted and the availability of vitamin-rich foods diminished, humans adapted to survive but at a cost to health. This adaptation presents significant implications for current health, particularly regarding immune function, infection response, and disease treatment. The article emphasizes the necessity of ensuring adequate vitamin C intake to mitigate these risks, especially in the context of modern health challenges. 

https://wattsupwiththat.com/2025/12/31/vitamin-c-and-climate/