The body has to pick a fuel source overnight. According to fitness YouTuber Thomas DeLauer, many people pick the wrong one. In a video titled "You're Burning Carbs in Your Sleep Instead of Fat," DeLauer argues that a large share of people burn carbohydrates during sleep instead of fat, and that switching that fuel preference is the key to faster fat loss. The claim attached to the video is blunt: the approach it describes shrinks 41% more fat.

That figure and the protocol behind it appear in a video that DeLauer produced as a paid partnership with the supplement brand Puori. The commercial relationship does not automatically disqualify the advice, but it sets the frame for how to read it. DeLauer is promoting a supplement subscription while explaining human metabolism, and the two goals are best kept separate.

The premise: fuel choice during sleep

The core argument rests on basic fuel physiology. During sleep, the body runs on stored energy. With insulin low and glycogen stores running down, it pulls from fat tissue. With insulin still elevated from a late meal, or glycogen still loaded, it burns carbohydrates instead. The difference matters for anyone trying to lose body fat, because the overnight stretch is the longest continuous window without food intake. Waste that window on carbs, the video argues, and you waste the most efficient fat-burning period of the day.

DeLauer's framing is that most people never reach that fat-burning state overnight, and the reasons come down to when they eat, what they eat, and when they eat again. The fix comes in two parts: what you eat before bed, and how long you wait before eating again.

Protein before bed

The first and simplest recommendation is protein before bed. The video flags it as a quick tip early on, and it is the least controversial piece of the presentation. The rationale is that protein before sleep supports muscle preservation overnight. More muscle means a higher resting metabolic rate, which means more calories burned around the clock.

Protein before bed is also the one piece of advice that happens to align with a supplement sponsor's product line. That is not a reason to reject it. It is a reason to notice that the advice is simple enough to follow without buying anything.

Fasting the right way

The second and larger piece of the protocol is fasting. DeLauer dedicates a section to "fast the right way," arguing that the length and timing of the fast matter more than whether you fast at all. The overnight window is already a fast. The question is whether you extend it into the morning and, in the more advanced version, push it much further.

The video includes a walkthrough of a 36-hour fast, which DeLauer calls "Monk" fasting. That level of restriction forces the body to deplete liver glycogen and lean harder on fat stores. But a 36-hour fast is an advanced tool, not a starting point. It carries real trade-offs, including hunger, low energy, sleep disruption, and the risk of overeating once the fast breaks. For most people, the practical version is simpler: stop eating earlier in the evening, and delay breakfast long enough that the overnight fast stretches into the morning.

The 41% figure presumably comes from one of the eight studies cited in the video description, and the video walks through the reasoning in timestamped segments from intro to recap. Without access to the specific study behind the number, the honest position is that this is a marketing claim attached to a real research base. Citation lists are not proof of specific conclusions, especially when the connecting logic is a YouTube edit.

The sponsorship question

The video opens with a disclosure that it is a paid partnership, and the description leads with a discount code: THOMAS at puori.com for 32% off a first order, plus a free shaker worth $25 when you start a subscription. That tells you what the video is, commercially, before you watch a frame of it.

The dietary advice does not depend on the product. Protein before bed and a properly timed fast require no supplement purchases. If the protocols work, they work because of the physiology, not because of a particular powder.

This is a familiar pattern in the fitness corner of YouTube. A creator builds an audience, lands a sponsor, and folds the sales pitch into the education. The format works because the advice is usually reasonable and the product is positioned as optional. The risk is that the dramatic framing exists to move viewers from watching to subscribing.

The bottom line

The valuable part of the video is its reminder that sleep is a fat-burning opportunity most people ignore. Eating close to bedtime and eating again too quickly after waking keeps the body in carbohydrate-burning mode around the clock. Pushing the first meal later in the day and making the last meal protein-heavy are low-cost changes worth testing.

The part to treat with caution is the 41% figure and the implied precision. Body composition results vary widely between individuals, and aggregated study numbers rarely translate directly to one person's experience. The protocol is reasonable. The exact percentage is a hook.

Watch the video for the metabolic explanation, skip the urgency, and check the referenced studies before you commit to a subscription.