Is it true that eating hot bread is harmful?

There is widespread concern that hot baked goods pose a gastrointestinal hazard. We decided to check whether such fear has a scientific basis.

About not eating hot baked goods, report federal Russian Media, sites about health and medicine, lifestyle media, information and sports portals Kazakhstan, Azerbaijan And Ukraine, sites shopsselling kitchen utensils. The problem of the potential dangers of hot bread interested users services questions and answers and forums. Among the speakers talking in the media about the potential harm from fresh baked goods, there are both popular representatives alternative medicine, and some nutritionists, and also amateur researchers.

Archaeological excavations carried out in 2018 in Jordan, testify that humanity began to bake bread from cereals more than 14,400 years ago, during the Epipaleolithic, that is, 4,000 years before the advent of agriculture. Before this discovery, it was believed that at first people switched to a sedentary lifestyle, mastered the cultivation of cereals, and only then learned to cook baked goods. However, the discovery of a piece of bread and bread crumbs in the Natufian hunter-gatherer culture disproved this theory. It turns out that first people collected wild plants and baked bread from them, and only then, to make their work easier, they learned to grow them at home.

The ancient baked goods consisted primarily of two ground plants: Triticum boeoticum and Bolboschoenus glaucus, and also contained traces of barley and oats. From this prototype of flour, ancient people made elastic dough, which they then baked, sticking it on the walls of fireplace pits - in a similar way that flatbreads are now prepared in a tandoor. 

The bread is probably played important role in ancient cultures. Baking required collecting the desired plants, removing the husks, grinding them into flour and then kneading the dough. This product was most likely served on special occasions and only to important guests. Bread from a variety of grains widespread in the culture of almost any nation and also plays a ritual role. His served as a greeting, included in a marriage ceremony, used in funeral rites.

However, you should not be afraid to eat this important product hot. All warnings about its dangers have no scientific basis. Let's deal with each in turn.

Firstly, there is no need to be afraid of “live” yeast that can occupy our digestive tract. Media scare, that the yeast in fresh bread “is so active that, even after entering the stomach, it continues to work actively and completely destroys all the beneficial bacteria that are inside. In other words, they very quickly destroy the beneficial microflora of the stomach. There is an immediate jump in acidity, which leads to the rapid formation of gastritis.” However, this fear is unfounded. Yeast of the species Saccharomyces cerevisiae (baker's yeast) die after just 1 min. at a temperature of 57.5 °C and after 0.1 min. at a temperature of 62 °C. However, bread cannot be baked at this temperature. Although recipes vary, baking requires much higher temperatures - industrial ovens work at 260 °C and above, and for home baking in the oven need to Preheat to at least 180°C. Under such conditions, the yeast will die almost instantly, and there is no way for it to colonize the digestive tract.

The second danger, as they say Media And Internet users, is is that the human body is hot baked digest unable to: “In the stomach, hot flour is not digested, but turns into a so-called food lump.” At the same time, the belief that fresh bread is not digested is quite old. Back in the 18th century, English doctors warned: “Any bread made from grain is never good until it is completely cool. Hot bread is extremely dangerous, it floats in the stomach and stimulates the production of phlegm.” At that time, the humoral theory dominated medicine. According to it, an imbalance of four fluids (blood, phlegm, black and yellow bile) in the body causes certain diseases. The said phlegm, or mucus, according to this idea, was responsible for the occurrence of influenza, colds and coughs. However, today the humoral theory is considered outdated, and in no case should you rely on it. Sylvester Graham, early 19th century American nutritionist thoughtthat only bread that has cooled for at least 12 hours is safe. He believed that all diseases occur due to overstimulation of certain organs. Graham blamed fresh bread for causing tooth decay and indigestion, as well as giving people impure thoughts and the desire to masturbate, which, according to his teaching, led to blindness and premature death. To save people from such temptations, a nutritionist has developed an alternative to bread - dry and tasteless crackers. However, his belief that hot bread increases the desire for self-gratification is not supported by any scientific evidence.

In the mid-19th century, Dr. William Beaumont spent eight years watched for a patient with a gastric fistula - a hole in the anterior wall of the abdomen that appeared after a bullet wound. During this time, he conducted 238 experiments related to digestion. In particular, his ward Alexis Saint-Martin ate various foods, and the doctor measured the time required to digest it. Hot toast with butter and coffee, according to his observations, digested record 4 hours 15 minutes and caused the patient discomfort and heaviness in the stomach. From this, Beaumont concluded that it is better to eat bread at room temperature. In 1858 he wrote: “Hot bread is never overcooked. Keep this in mind, readers, if you are used to eating cookies with tea or warm bread that looks so delicious on your table during breakfast. After tumbling around in the stomach for a long time, it will begin to ferment and eventually exit the stomach as an unwanted tenant of this delicate organ, but it is never digested, never converted into suitable nutrition for the body. This is a recipe for indigestion. The above is completely true, as has been repeatedly proven by actual observation.”

In fresh baked goods, the starch particles from the flour are saturated with water (hence its slightly sticky texture). As the water evaporates, it turns into resistant starch. The first one is more easily absorbed by the body, since the sugars from it are more accessible. This food is faster increases insulin levels, which can stimulate appetite and promote weight gain. Resistant starch takes longer to digest, and it's also harder for our cells to absorb the sugars it contains, meaning stale bread causes a smaller spike in insulin. In 2008, British scientists analyzedhow eating white bread at different temperatures affects insulin production. Ten healthy volunteers participated in the experiment. They ate a serving (50 g) of different breads, homemade or store-bought, in one of four types:

• fresh;
• frozen immediately after cooking and then thawed at room temperature;
• fresh, toasted;
• frozen immediately after cooking, thawed at room temperature, and then toasted in the toaster.

Of homemade bread, the greatest increase in blood glucose was caused by fresh bread; the peak occurred 45 minutes after consumption. In second place were two types: frozen immediately after cooking, and then defrosted at room temperature and fresh, toasted in a toaster. Finally, frozen immediately after cooking, thawed at room temperature, and then toasted caused the smallest spike in blood glucose. However, the difference was only 1 mmol/l, and the effect lasted just over 1.5 hours. In the case of store-bought bread, fresh was again in first place, but the peak in blood glucose occurred in about the first half hour after consumption. Both toasted pieces had the least effect on glucose levels. The effect of use also turned out to be very short-lived. In terms of blood sugar control, fresh baked goods are the least beneficial, meaning that people with diabetes are better off eating toasted bread, but for healthy people there is likely to be no significant difference. At the same time, this experiment shows that there is no point in fearing that hot baked goods are not digested, otherwise no absorption of nutrients would occur and the glucose level would remain unchanged.

The only category of people for whom eating both freshly baked and cooled bread may be contraindicated are patients with celiac disease, that is, gluten intolerance. However, there is also for them exceptions - for example, bread made from corn or rice flour. People with celiac disease will experience symptoms of indigestion when consuming gluten. Perhaps Dr. Beaumont had a person with exactly this diagnosis as a patient, which is why his observations turned out to be distorted.

Thus, there is no danger in enjoying a delicious crust of freshly baked bread, a slice of hot pizza or pies just taken out of the oven, without waiting for these products to cool to room temperature. Yeast dies almost instantly at temperatures just above 60°C and does not affect the gastrointestinal tract. And beliefs about the dangers of hot bread were popular back in the 18th century, but there is no evidence that the human body cannot digest such food.

Cover image: Image by enow from Pixabay

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