You may have also heard that InFa can preserve more muscle mass. These are strong claims with loose research to back it up. From the research that is available, we can’t conclusively say that this is true. These claims are essentially being derived from subjective evidencepieced together with other evidence and research. When we fast, our growth hormone (GH) levels go up, and when we feed they go down. This increase in GH is the underlying mechanism of reason to suggest that there is a preservation of lean muscle mass in a InFa based diet.
The metabolic effects of GH are complex and involve increased lipolysis and hyperinsulinemia (increased insulin levels) both which have protein anabolic properties. Between these potential secondary mediators, lipid intermediates have been shown to stimulate protein synthesis and insulin to inhibit breakdown to act through both mechanisms. These effects have also been observed in long fasting periods (16-40hrs) showing that the raw evidence is certainly there, and very easy to make a case defending the ideology that InFa preserves lean muscle mass and burns predominately fat mass. However, we still can’t say for certain, what we do see from literature is that it can induce weight loss.
Is it better than other methods? I believe that the answer to that question is subjective and based on the individual. So long as the caloric ratio is proper, you will experience weight gain or weight loss, and how you go about that in terms of quality of nutrients and timing of intake is up to the person.What we do know from animal models is that alternative day fasting (24h+) can promote life span longevity, lower risks of cancer, promote brain health and reduce risks of brain disease, improve cognitive function and positively influence metabolic pathways. When it comes to doing modified nutrition timing/intermittent fasting, we can’t support these claims. Like many diets, there are subjective claims of improved cognition, weight loss, sleep quality and energy/performance levels. There is some minor research out there to back these things up, but there are similar improved outcomes with other dietary lifestyles as well (Keto, Vegan, etc).
So, is it the diet? Is it placebo? Probably both. The best way to go about choosing a diet, in the end, is finding what is most sustainable for your lifestyle!
Tyler Baron, Student at CMCC, Physique Competitor