27/09/2025
Why do we need to have vitamin C in our daily diet?
You have probably heard that vitamin C is great for your immune system, but this powerful nutrient does so much more for your body than you might think. Unlike most animals, humans can’t make their own vitamin C, which is why it is considered an essential nutrient. We have to get it from our diet every single day. It’s thought that we lost this ability because our ancestors’ diets were so rich in this vitamin that we no longer needed to produce it.
So, what exactly does vitamin C do for us?
- Immune System Support: Vitamin C helps your body produce white blood cells, which are essential for fighting off infections and diseases. It also has antiviral, antifungal, and antibacterial properties, and can even help reduce the severity of allergic reactions.
- Collagen Production: This vitamin is critical for creating collagen, a vital protein for healthy skin, hair, nails, bones, teeth, and blood vessels. It’s also needed to produce elastin and other key components of your body’s connective tissues.
- Antioxidant Properties: As a powerful antioxidant, vitamin C helps protect your cells from damage caused by harmful molecules called free radicals. This can help lower your risk of chronic diseases like cancer, heart disease, and arthritis.
- Nutrient Absorption: Vitamin C is necessary for your body to properly absorb iron from plant-based foods and supplements. This is key for producing red blood cells and preventing anemia. It also helps your body use other nutrients, like B vitamins.
- Neurotransmitter Synthesis: Vitamin C is crucial for making neurotransmitters like dopamine, noradrenaline, and acetylcholine, which regulate your mood, focus, motivation, and even your sex drive.
- Metabolic Functions: It plays a role in regulating blood sugar and converting cholesterol into bile acids, which helps your body process toxins and break down dietary fats.
What Happens If Your Vitamin C Is Low?
While severe vitamin C deficiency, known as scurvy, is rare today, having low levels of this nutrient can contribute to a variety of chronic health issues. Historically, scurvy was a common killer of sailors on long voyages without fresh produce. We’ve known since the 1500s that fresh fruits and vegetables could prevent it, and in 1747, a controlled trial by James Lind proved that citrus fruits were the key. Vitamin C was the first vitamin ever discovered in 1912.
Today, you might be at a higher risk of deficiency if you:
- Can’t eat fresh or minimally processed foods (due to income, age, or health issues).
- Are exposed to large amounts of toxins (heavy metal toxicity, mold exposure, chronic infections).
- Take a lot of pain relievers like Advil or aspirin.
- Are undergoing chemotherapy.
- Suffer from conditions like autoimmunity or cancer.
- Smoke, drink alcohol, or use drugs.
- Have a condition that affects nutrient absorption, such as celiac disease, IBS, or Crohn’s disease.
Preserving and Supplementing Vitamin C
Because vitamin C is a water-soluble nutrient, it’s sensitive to heat, light, and air. It can lose anywhere from 10% to 90% of its potency during food processing. This is why focusing on fresh foods and avoiding overcooking is so important.
While many people take vitamin C supplements, it’s important to be mindful of your intake. The Upper Limit (UL) for vitamin C is set at 2,000 mg/day – 4,000 mg/day to avoid side effects like diarrhea, nausea, and stomach cramps. Since vitamin C is water-soluble, your body simply excretes the excess.
However, be aware that chronic, high-dose supplementation can lead to issues like excess iron absorption, which increases oxidative stress, or can even contribute to vitamin B12 deficiency and dental enamel erosion. It’s always best to get as much of your vitamin C as you can from a balanced diet and consult with a healthcare professional before starting any high-dose supplement regimen.
