Pretty interesting read from Dr. Serrano
Vitamin C
Sources: The best sources are fruits like: strawberries, cantaloupes, peppers, oranges, lemons, and grapefruits.
Absorption and Storage: Vitamin C is easily absorbed. Average absorption is 90%. For intakes between 20 and 120 mg; however, at very high intakes absorption rates decrease. Persons that regularly use Vitamin C supplementation have much higher serum levels of Vitamin C than non users.
Maximal absorption is attained by the ingestion of several spaced dosages of 500 mg to 2 grams throughout the day. Vitamin C's half-life is 3 to 4 hours. This means you need to take Vitamin C every 4 to 6 hours to keep your levels elevated. Peak serum concentration is obtained in about 2 1/2 hours. To increase serum level of Vitamin C by a factor of two you have to increase the oral dose by a factor of 10. For example: going from 50 to 500 mg per day doubles serum levels. Going from 500 mg to 5 g (5000 mg) per day doubles the serum level again. So going from 50 mg daily to 5000 mg raises your serum level of Vitamin C to four times the original amount.
Functions and Biological Activity of Vitamin C
Listed below are ten claims that have been made in the research for Vitamin C. Next to each claim I will give a letter grade to coincide with what research tells us and a number grade that tells what my personal experience has indicated (see the grading key below):
Research:
A - adequately backed up by research
B - backed up but still not enough
C - controversial 30% say it works 60-70% it doesn't
My Grading:
1 - definitely see results with my patients > 70%
2 - some results, 50%
3 - nothing
4 - unable to grade
Cost:
$ - No way Jose, I will not spend money.
$$ - If I've extra money
$$$ - Definitely, I will spend the money even if I don't have it.
1) Vitamin C Increases Iron absorption [A,1] - Especially important for women, since menstrual periods decrease iron levels. Low iron levels can result in decreased stamina and performance.
2) Aids in Collagen Synthesis [A,4] - In theory this could be very important for a bodybuilder. However, I have not been able to document this benefit in my practice one way or the other so I give it a grade of 4.
3) Aids in the Synthesis of Carnitine [A,4] - Theoretically this should help the bodybuilder to mobilize more fat. I, personally, do not have enough data or experience with my patients to agree or disagree with the research.
4) Helps Reduce Soreness and Joint Pain [A, 1] - This is one benefit related in the scientific data that I've definitely seen with my patients.
5) Acts as an Antioxidant [A, 1] - Antioxidants are vitamins or minerals that prevent free radical build up in the body. Exercise causes an increase in free radical build up which limits the body's ability to repair. Free radicals can cause DNA damage, muscle soreness and disease. Vitamin C has excellent marks here.
6) Reduces Susceptibility to Injuries and Disease [A, 1] - Free radicals can cause your immune response to decrease, which in turn increases your susceptibility to disease and injuries. All my patients respond well to higher doses of Vitamin C. White blood cells increase and viral infections decrease in almost every instance.
7) Aids in Production of Serotonin [B, 3] - Increased Serotonin levels in the brain have a positive effect on one's ability to sleep soundly, depression and the natural secretion of growth hormone. This sounds good, but higher serotonin levels can also lower your threshold for fatigue.
8) Reduces Cholesterol and Prevents Arteriosclerosis [A, 1] - Everybody should use Vitamin C because it help prevents hardening of the arteries while reducing cholesterol by 30%. Enough said!
9) Reduces Asthma / Allergies Susceptibility [A, 1] - New research shows that people can decrease asthma attacks and allergic reactions by just increasing Vitamin C uptake by as little as 200 mg. I've seen a number of my patients discontinue their allergy medication by simply increasing their intake of Vitamin C.
10) Reduces Cortisol Levels [A, 1] - Very important for bodybuilders, research shows that Vitamin C intake of 2 to 5 grams, up to 15 grams a day definitely reduces the Cortisol response to stress (training). Thus Vitamin C helps prevent catabolism.
Conclusion
I use Vitamin C and definitely recommend it to my patients. I recommend that you start with 1500 mg to 6000 mg divided into three daily doses and go up to a maximum of 5 to 10 grams per day. The most important times to take Vitamin C are one hour prior to training and two hours after your workout is completed. By ingesting 2 to 4 grams at these times the Cortisol response will be minimized and the antioxidant effect of Vitamin C maximized. Your Vitamin C should be time released to keep serum levels constant. Never buy chewable tablets as this form will destroy your tooth enamel. Back off the dosage if you experience diarrhea or stomach upset. These symptoms are an indicator of the maximum dosage you can tolerate.