I Tried Collagen Fasting for 36 Hours, Here’s What Happened (and my protocol)

DeLauer designed this protocol as a reaction to fad 'sugar diets' and his dissatisfaction with bone broth fasts. He wants to combine the benefits of fasting (mental clarity, gut rest) with the restorative properties of collagen and glycine. He believes that by eliminating all other food, the collagen peptides are more efficiently directed toward connective tissue and gut repair. He emphasizes that glycine's antioxidant and calming effects counter the stress response of fasting, and that working out is essential to still trigger autophagy. He also suggests sauna. He used Bubs collagen for its purity and grass-fed sourcing. The protocol is meant to be simple and inexpensive.

DeLauer emphasizes that pure glycine is the key component for the calming effect. He cites established literature supporting 3g for sleep and memory. He adds it to his protocol specifically to counteract the mental 'loudness' and norepinephrine surge of fasting. The cost is low and the evidence is strong, making it a easy add-on.

DeLauer describes his protocol as a 'restorative fast' rather than a 'breaking down' fast. He argues that collagen's high glycine content (33%) acts as an antioxidant, reduces reactive oxygen species, and provides a calming effect that counters the typical norepinephrine spike from fasting. He also notes that collagen peptides act as signaling molecules for connective tissue protein synthesis, not just as generic protein. By eliminating other foods, he believes the body can direct these peptides more efficiently. He acknowledges a lack of direct scientific evidence but connects existing research on glycine, collagen, and gut mucosal support. He contrasts this with 'sugar diets' and sees it as a more metabolically productive alternative.

DeLauer admits that collagen and glycine blunt autophagy, which is one of the primary benefits of fasting. However, he reframes glycine as having cytoprotective effects, specifically in the liver, that protect cells without necessarily recycling them. He suggests that exercise—whether resistance training or cardio—independently induces autophagy, so by working out during the fast, one can still achieve cellular cleanup. He also mentions sauna as another autophagy trigger. This reframing allows the protocol to be seen not as losing autophagy but shifting to a different form of cellular maintenance: building and protecting instead of just clearing out.

DeLauer explains that during fasting, the brain's prefrontal cortex is highly active because it's signaling to find food, leading to a 'loud' brain and difficulty turning off the default mode network. This results in high norepinephrine and adrenaline, causing insomnia. Glycine, being an inhibitory neurotransmitter and antioxidant, helps calm the nervous system. He took 3g of glycine before bed, the dose supported by literature for sleep and memory. He notes that having collagen and glycine allowed him to sleep, unlike his usual multi-day fasts where he gets very little sleep. The improved sleep likely contributed to feeling better overall.

He contrasts collagen powder with bone broth, noting that while bone broth contains collagen, the concentration is much lower and it's expensive. Collagen powder provides a more affordable, higher-concentration source of the amino acids needed for gut mucosal repair. He speaks from a history of gut issues (ulcerative colitis, IBS) and says that the targeted amino acid support during the fast left his gut feeling 'smoother' and calmer than ever, akin to an extended water fast. He also speculates that collagen aids gut mucosal hydration. This direct gut-soothing effect, combined with the absence of other food irritants, might be the mechanism behind the dramatic gut relief.