Vitamin C as an Energy-Booster
Fatigue is reported anywhere between 7 and 45% of the population in the United States. With our busy and increasingly stressful lifestyles, many of us are looking for any way possible to optimize our energy levels. According to one study of almost 30,000 adults in the U.S., nearly 40% of workers experience fatigue on a daily basis. What if, instead of grabbing that 3 pm Red Bull, you could optimize your nutritional status and have sustained energy? Well, research suggests that diet may be an important factor in energy levels.
Aside from the fact that food directly provides calories to be used for energy, several micronutrients play an important role in offsetting fatigue. For example, anti-oxidants like vitamins C and E can decrease oxidative stress in the body, which has been considered a biomarker for fatigue. In fact, after a 2-week period of overworking, subjects showed increases in oxidative stress. (Fukuda et al. 2016)
Vitamin C as an Energy-Booster
Vitamin C is a potent anti-oxidant, and therefore has the ability to decrease the oxidative stress related to fatigue. It has been studied for both its ability to boost energy levels and to reduce fatigue and offers promising results.
In one study, 10 g of intravenous vitamin C was given to office workers between the ages of 20 and 49. After 2 hours, the vitamin C–treated group showed significantly lower fatigue scores than the control group, and the scores remained lower for an entire day. The vitamin C group also had lower oxidative stress than the control group. (Suh et al. 2012)
Vitamin C Status and FatigueA study at the University of Alabama Medical Center looked at the connection between vitamin C intake and fatigue in 411 dentists and their spouses.
- Those who consumed less than 100 mg/day of ascorbate (vitamin C) had an average exhaustion index of 0.81, whereas those ingesting more than 400 mg reported an exhaustion index of 0.41.
- So, individuals consuming just the RDA reported about twice the fatigue as those taking as much as 7x the RDA.
- This study also found that the average 57 year old ingesting nearly 7x the RDA for vitamin C showed a mean exhaustion score less than the average 33 year old who was consuming just the RDA. (Cheraskin et al. 1976)
Are Kiwis the New Coffee?Kiwis are known to be very high in vitamin C. In fact, 100 g of kiwi contains 3X the amount of vitamin C as you would find in 100 g of an orange! Because of this, researchers set out to see if supplementing diet with kiwi could have positive impacts on mood and energy in college students with suboptimal diets. 134 male college students were supplemented with a ½ kiwi per day or 2 kiwis per day in addition to their average intake of 3 servings of a fruit or vegetable per day, and their mood disturbance scores were calculated at baseline and after the intervention.
- The 2-kiwi group saw a 35% decrease in total mood disturbance (TMD), and a 32% decrease in depression score.
- In the portion of the group with higher baseline mood disturbance scores (split at mean), supplementing with 2 kiwis showed a 38% decrease in TMD score, a 38% decrease in fatigue, and a 31% increase in vigor. (Carr et al. 2013)