Supermarket shoppers often bypass the yellow-stickered bread nearing its sell-by date, but a surprising scientific insight suggests we should be grabbing these bargains. Experts are now advocating a simple two-step kitchen process that can transform ordinary bread into a far healthier option for your gut and blood sugar levels.
The Science Behind the Freezer Hack
The advice stems from a study published in the European Journal of Clinical Nutrition by researchers P. Burton and H. J. Lightowler. Their work discovered that putting bread in the freezer before toasting it significantly alters its impact on the body. The key lies in a process called retrogradation.
As explained by dietitian Abbey Sharp to her one million TikTok followers (@abbeyskitchen), when starchy foods like bread, rice, or pasta are cooled, their starch molecules rearrange. This transformation creates a type of fibre known as resistant starch. "Resistant starch is resistant to our digestion, but our gut microbes can use them as fuel," Sharp noted.
What the Research Revealed
The study involved testing both commercial supermarket bread and homemade white bread on ten participants, comprising three men and seven women aged between 22 and 59. The results were compelling.
Scientists measured the blood glucose response, finding a marked reduction when bread was frozen and then toasted. For homemade white bread, toasting after freezing and defrosting led to a 39.4% reduction in the glycaemic response. The same process with commercial white bread showed a 26.1% reduction.
"Freezing and then defrosting bread reduces the glycaemic response by 30%, while freezing, thawing and then toasting reduced it by 40%," Abbey Sharp summarised from the research.
A Dual-Purpose Life Hack
This finding turns a common money-saving practice into a powerful health strategy. The advice is clear: buy discounted bread about to expire, freeze it immediately, and defrost slices as needed by popping them directly into the toaster.
Online commenters have echoed the benefits, particularly those managing blood sugar levels. One user with type 2 diabetes stated, "I meal prep meals with rice and they don’t spike my BS the way they do if I eat them fresh." Another with type 1 diabetes confirmed a similar effect with reheated pasta. A third simply celebrated: "I've been freezing bread for yearssss to save money. I’m glad it’s a little hack for your health too."
This simple method of freezing and toasting bread offers a practical, evidence-based way to support gut health, manage blood sugar spikes, and reduce food waste—all while saving money at the till.
