The safest general approach is to thaw slowly rather than quickly. Moving frozen food from the freezer to a fridge the night before it's needed gives it time to thaw evenly without sitting at room temperature for hours, which is where bacterial growth becomes more of a concern. Where a fridge isn't practical, a sealed bag placed in room-temperature water, changed periodically as it cools, is a commonly used alternative that still avoids the extremes of very hot water or direct heat sources, both of which can affect the food unevenly and pose a burn risk if used carelessly.
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It's also worth remembering that gut-loading is one part of a wider feeding picture, alongside supplement dusting and an appropriate feeding frequency for the animal's life stage. None of these replace the others, and none of them are a substitute for professional advice if an animal's diet or condition is a genuine concern.
For anyone building frozen food into a regular routine for the first time, [checking the range of frozen food sizes and pack options](https://reptilecentre.com) is a sensible way to match portion size to the animal being fed, so thawing quantities aren't left to guesswork.
Many keepers separately notice reduced interest in food around shedding, and some notice it easing off at certain times of year. These are common observations across a lot of collections, but they're not something we can confirm or rule out for your own animal from here, which is exactly why a change in appetite is worth flagging to a reptile-experienced vet rather than waiting to see what happens.
The logic is straightforward. An insect that has been kept on nothing but its packaging for days offers less nutritional value than one that has spent time eating a varied, nutrient-dense diet. Gut-loading closes some of that gap by treating the feeder insect as a genuine part of the food chain rather than an afterthought.