# The Influence of Various Types of Functional Bread on Postprandial Glycemia in Healthy Adults
## 4 Discussion
Whereas the IAUC is also lower in the group named others (where the dominant flours are mainly oat, buckwheat, or a mix with wheat and rye) than in the wheat/spelt group, we might assume that this effect is related to a significant lower carbohydrate content than in the remaining two groups. In a given group, there was also an inverse relationship between IAUC and protein content and fiber/carbohydrate ratio. Irrespective of the type of flour, we have shown that the mean glycemic index value is significantly lower in products made from whole-grain flour. In cereals, bioactive compounds (including lignans, phenolic acids, plant sterols, folates, tocopherols, and minerals) are concentrated in the germ and the bran, richest in dietary fiber. Therefore, whole-grain products exhibit several health-promoting properties, including reducing the risk of diabetes, cardiovascular disease, and weight gain, improving gut microbiome composition, and thus, boosting immune response [38; 39]. [PERSON] et al. classified two-thirds of bread as a medium- to high-GI food (the average glycemic index of bread is estimated at 64). This is the most frequently studied group of carbohydrate products and mainly concerns various types of bread made from wheat flour or wheat and rye flour or other flours, e.g., rice or corn flour, and less frequently bread with added oil seeds such as sunflower seeds, pumpkin seeds, or flax seeds. Such additives usually increase the fat content at the expense of carbohydrate content in the bread being studied, affecting their fiber content to a varying degree [40]. In our study, the most common additives to bread were sunflower, flax, pumpkin seeds, legumes such as soybeans, lentils, and chickpeas. The glycemic index of the assessed bread with oily grains in most of it was within medium borders (median 57.5, 6 out of 14 had low GI). Similarly, [PERSON] et al. observed that, for the addition of soy grain and flaxseed to wheat bread, the average GI values were close to the limit of values considered average (about 60) [41]. [PERSON] et al. observed that the addition of flax seeds to tortillas increased the fat and fiber content while reducing starch hydrolysis, which may affect the GI value [42]. Pumpkin seeds, flaxseeds, sunflower, and legumes are also a source of alpha-linolenic acid, oleic acid, as well as chromium, zinc, cobalt, nicotinic acid, fitstorels, tocopherols, lignan, trigeline, and polyphenic compounds (including p-hydroxybenzoic acid, caffeic acid), which affect insulinemia and glycemia [43; 44; 45; 46; 47]. Adding pumpkin or flax seeds to a meal reduced postprandial glycemia in healthy adults [48; 49; 50] and in people with impaired carbohydrate metabolism [46]. The addition of flax and pumpkin seeds may delay absorption within the gastrointestinal tract, improve hepatic insulin sensitivity, decrease hepatic glucose output, and increase insulin secretion [51]. In this study, it was observed that breads with added oilseeds significantly reduced blood glucose levels in the second hour after their consumption compared to breads without added grains and the change in glycemia after consumption of bread with added oilseed was positively correlated with protein and fat content. The glycemic index value of bars based on flaxseeds, rich in fiber, unsaturated fatty acids, and protein, with a significant content of lignans, was, on average, 30, with significantly higher satiety. The lignans in flaxseed can decrease blood glucose concentrations by inhibiting pancreatic alpha-amylase or by increasing the sensitivity and response of target cells to insulin [52]. The effect of flaxseed products on postprandial glycemia may also be related to the influence of active peptides contained in them, which inhibit the activity of dipeptidyl peptidase IV (DPP IV), increasing the postprandial utilization of glucose [53]. In our work, we also tested bread by adding various oilseeds. However, the averaged results do not confirm that bread with added seeds always has a lower GI.