Study Confirms Antioxidants (C+E) Are Bad For Healthy People Who Train, But in Some Subjects C+E Increase the Fat Loss Effects of HIIT + HIT by a Whopping 60%

The anti-long-term health, but pro short term fat loss effects of vitamin C + E
I must admit that I filed the study by Paulsen et al. (2014; accepted manuscript) under "further evidence that high doses of anti-oxidants do more harm than good to active individuals" the very moment I posted the information from the corresponding press release in the SuppVersity Facebook News (read it!).

A couple of days ago, I wanted to cite the paper in a different context and took a closer look at the actual results (yeah, even I sometimes only read the abstract) and as it turns out,...

...the scientists left out some information, you may be interested in, ...

...even though it may not be relevant from a statistical perspective. How I know things about your interests?Based on the visitor statistics of the SuppVersity. I just have to take a brief look at them to know that the vast majority of you will be intrigued to hear that the "daily vitamin C and E supplementation" (1000mg vitamin C and 235mg vitamin E per day), although it may have "attenuated increases in markers of mitochondrial biogenesis following endurance training", led to an albeit non-significant, but highly conspicuous 60% increase in body fat reduction.
Figure 1: Pre- & post-levels of body fat mass (left, in kg) and relative changes in type I and type II muscle fiber size (right; in % of baseline) in the subjects in the vitamin C + E and placebo arm of the study (Paulsen. 2014)
Yes, I know. The inter-group difference did not reach statistical significance. If you look at the exact figures, though you will have to concede that the intra-group difference did. In other words: While the subjects who took the anti-ergogenic anti-oxidants lost a significant amount of body fat, those who took the placebo did not. This is because the fat loss in the supplementation groups was much more evenly distributed than in the placebo group (the corresponding standard deviations were "only" 1.6x, not 3.6x (placebo) higher than the average fat loss of -5.3kg).
Table 1: Overview of the exercise component of the study (Paulsen. 2014)
Due to the minimal loss or marginal gain of lean body mass (and fiber size; see Figure 1) in the vitamin and placebo group, respectively, the relative difference of the change in body fat % (-4.6% in the vitamin and -2.0% in the placebo group) is even more pronounced.

This does not mean that these effects on the body composition are "real", i.e. actually due to the provision of vitamin C + E. What it does mean, though is that the occurred, although there was no visible training effect on the mitochondrial capacity and thus in the absence of any visible / measurable training effects.
The fat loss effects are not significant and my ad hoc hypothesis to explain them merely speculative. Therefore I still advice against the use of high dose "kamikaze" antioxidants (mere ROS-scavenger) like vitamin C + E - not just in the vicinity of a workout, but in general.
The absence of structural changes and the corresponding long-term health benefits that will always outweigh those of temporary reductions of body fat, should be reason enough to understand that someone who is not sick and chronically inflamed as the animals and human subjects in the studies you will see referenced in the write-ups of the supplement industry not to consume copious amounts of vitamin C, vitamin E or NAC.
Bottom line: I am certainly no advocate of high dose vitamin supplements and there is accumulating and in my humble opinion convincing evidence that they blunt the adaptive response to exercise training - including the potentially life-saving changes in mitochondrial capacity.

Still, the data from the Paulsen study does also support the conventional wisdom that a high level of baseline inflammation hampers the loss of body fat and that in spite, or rather because of the fat-burning prowess of IL-6, of which Knudsen et al. (2014) have recently been able to show that it is responsible for the exercise induced increase in UCP1 expression in subcutaneous white adipose tissue that will have your love handles melt away.

That does not make sense? Well, maybe it does. If you think about it as a vitamin-induced alleviation of the IL-6 analog to insulin resistance that allows the fat cells to finally "see" the IL-6 again and would thus propel the loss of body fat in those of the 14 women and 13 men in the supplement arm of the study who had a high baseline inflammation and correspondingly low "IL-6 sensitivity", this would be similar to the beneficial effects of ALA on weight loss int he obese and their absence in lean people.
  • Knudsen, Jakob G., et al. "Role of IL-6 in Exercise Training-and Cold-Induced UCP1 Expression in Subcutaneous White Adipose Tissue." PloS one 9.1 (2014): e84910.
  • Paulsen, G, et al. "Vitamin C and E supplementation hampers cellular adaptation to endurance training in humans: a double-blind randomized control trial." Journal of Physiology (February 2014; accepted manuscript).
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