Humans cannot make their own Vitamin C, as we lack the enzyme gulonolactone oxidase, the final step of the biosynthetic pathway. Thus we must obtain this crucial vitamin from our diet. In the diet, Vitamin C mainly comes from fruits and vegetables. Otherwise supplementation with a pill, powder or tablet is necessary to prevent deficiency. Vitamin C is necessary to prevent scurvy, a deficiency which leads to weakened bone and teeth.
Essential roles of Vitamin C in your body
- Collagen formation promoting healthy skin, hair, nails and bone
- Carnitine formation: a fatty acid used to generate ATP (energy for cells) in the mitochondria; the heart uses a lot of carnitine for energy production
- Supporting neurotransmitter formation including norepinephrine & serotonin
Vitamin C is important in the cellular oxidation and reduction cycles, where Vitamin C donates an electron to regenerate other substrates. In particular, Vitamin C helps to reduce Vitamin E (another potent antioxidant) so that it may continue to act as a free radical scavenger.
There was some controversy in the literature about Vitamin C being a pro-oxidant and what this means is that some in vitro studies (non human) showed that at higher dosages (we are talking 10+gms, not mg) of ascorbate mixed with blood, Vitamin C caused an increase in reactive oxygen species (ROS). ROS are present in humans and they have many functions including blood vessel dilation (NO) and free radical scavenging (H2O2, O2) which are important to our immune system. Vitamin C was shown to help promote this, which at daily RDA levels and therapeutic levels (up to 2-3 gms daily) is actually beneficial. In addition to having Vitamin C around, having other antioxidants in the body helps to negate any increase in ROS that may get out of control!
Vitamin C for treating conditions
In the research, Vitamin C has shown promise for treatment in various conditions:
- In the treatment of reducing hyperhomocysteinemia, an independent risk factor for cardiovascular disease
- Improving glutathione recycling, the body’s main antioxidant
- Used in conjunction with Vitamin E to lower the risk of Alzheimers
- Reduction in risk of stroke
- Ability to selectively kill cancer cells through increasing H202 (hydrogen peroxide) in cells, a necessary free radical initiating cell death.
Often I recommend Vitamin C to bowel tolerance (generally 1-3gm daily) to help those who are sick recover faster. This means that you can take 500mg every few hours until you notice your stools get loose. Then you can back down by 500mg and use this as your daily dose until you are 100% recovered (not just until your symptoms lessen but until you are symptom free & feeling better).
To help prevent the cold and flu, use 500-1000mg daily.
For those experiencing increased inflammation in general such as those who smoke or who have heart disease (500mg-2gm daily), for those who experience fatigue from an overstressed lifestyle (500-1000mg daily of a time released), and for those who need assistance with wound healing such as those with Diabetes (500mg-2gm daily).
Other Vitamin C Benefits
- Form an important protein used to make skin, tendons, ligaments, and blood vessels
- Heal wounds and form scar tissue
- Repair and maintain cartilage, bones, and teeth
- Block damage caused by free radicals (the buildup of free radicals over time is largely responsible for the aging process)
The following foods are rich in Vitamin C
In order from highest to lowest, all providing more than 100% per serving (RDA of 100% is 75-120mg). And no oranges aren’t on the top of the list, they are actually on the bottom. But remember ALL of the fruits and vegetables below are EXCELLENT sources of Vitamin C!
- Bell peppers
- Brussel Sprouts
For additional information check out this Vitamin C page from the National Library of Medicine.
Your Wellness Expert,
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