Vitamin C

Vitamin C or ascorbic acid is a water-soluble molecule that is not synthesized by the body and is eliminated more quickly than lipo-soluble vitamins. Partially eliminated in the urines, it must be ingested regularly. Vitamin C is found in many types of food however, some have a higher content of vitamin C than others. Citrus fruits, fresh fruits and green vegetables are the richest in vitamin C.

The use of vitamin C to give back strength to tired and energy-starved people has been known for a long time. Vitamin C is indeed involved in many intracellular mechanisms and participates actively in the proper functioning of the body. Subjects suffering from Vitamin C anemia typically present symptoms of fatigue and loss of energy.

The punctual catch of the vitamin C fights the state of temporary tiredness, while a prolonged cure limits the episodes of weakening. Vitamin C is known to act effectively on people in good physical condition, as well as on weakened or tired people. This is the reason it is often found in the composition of food supplements aimed at restoring vitality and energy.

When vitamin C is supplied in adequate amounts through diet, its biochemical properties translate into normal physiological functions. In case of suboptimal or inadequate nutrient status may be associated with functional deficits leading to symptoms of fatigue, irritability, low mood and muscle pain.

From a biochemical perspective, one of the main causes of fatigue is oxidative stress. Inflammatory cytokines in the body are correlated with increasing symptoms of fatigue. One study investigating the effect of intravenous vitamin C on fatigue in office workers, indicated decreased fatigue scores, higher vitamin C levels and lower oxidative stress in the vitamin C group after 2 hours and for one day compared to the control group.|1|$Suh S.Y., et al. (2012). Nutr. J., 11, 7.$ 

A clinical study examined the impact of vitamin C on physical activity and respiratory tract infections during the peak of the cold season in healthy adults with adequate-to-low vitamin C status for 8 weeks. The participants supplemented with vitamin C reported significantly less cold episodes, compared to placebo intake, and cold duration was reduced.|2|$Johnston C.S., et al. (2014). Nutrients, 6, 2572-2583.$ Vitamin C has an antioxidant activity, donating its electrons to scavenge for and neutralize reactive oxygen species (ROS).

1 Suh S.Y., et al. (2012). Intravenous vitamn C administration reduces fatigue in office workers: A double-blind randomized controlled trial. Nutr. J., 11, 7.

2 Johnston C.S., et al. (2014). Vitamin C supplementation slightly improves physical activity levels and reduces cold incidence in men with marginal vitamin C status: A randomized controlled trial. Nutrients, 6, 2572-2583.