Major Research Findings

Epidemiological studies have shown that fiber intake is associated with a lower body weight. 1 . This effect could be explained by satiety and energy intake. However, the types and doses of fiber that effectively reduce appetite and energy intake are not yet clear. 1 .

Transglutaminase treatment has been found to affect the digestibility of proteins. 3 . This treatment may enhance gastric digestion while suppressing initial intestinal digestion. 3 .

The effect of adopting a low-fat versus a low-carbohydrate weight loss diet on fiber intake is of interest but not well documented, especially when both approaches promote high-quality food choices. 2 . The DIETFITS study showed that the low-fat group consumed more dietary fiber than the low-carbohydrate group over 12 months. 2 . However, the low-carbohydrate group still consumed reasonable amounts of fiber from plant-based protein and fat sources, such as nuts and seeds. 2 .

Different dietary protein levels during 12 to 26 weeks were found to improve growth performance, bone quality, and testosterone levels in male guinea fowl. 4 . The higher protein group exhibited enhanced growth performance, improved bone density and strength, and increased testosterone levels. 4 . On the other hand, the lower protein group showed improved bone robustness. 4 .

Treatment Summary

While fiber intake is considered a potential way to increase satiety and reduce energy intake, 1 , most fibers did not reduce appetite or energy intake in short-term study designs. 1 . β-glucan, lupin kernel fiber, rye bran, whole grain rye, or a mixed high-fiber diet showed satiety-enhancing effects in multiple studies. 1 .

Transglutaminase treatment can affect the digestibility of proteins, enhancing gastric digestion but suppressing initial intestinal digestion. 3 . Soybean protein is more susceptible to the effects of transglutaminase treatment compared to myofibrillar protein, possibly due to its higher glutamine content. 3 .

The DIETFITS study showed that the low-fat group consumed more dietary fiber than the low-carbohydrate group over 12 months. 2 . The low-carbohydrate group still consumed reasonable amounts of fiber from plant-based protein and fat sources, such as nuts and seeds. 2 . Non-starchy vegetables were the primary source of dietary fiber in both diet groups. 2 .

Feeding guinea fowl with 19% crude protein from 12 to 26 weeks improved growth performance, bone density and strength, and reproductive organ size. 4 .

Benefits and Risks

Benefits Summary

Fiber intake is associated with weight loss, 1 , and β-glucan, lupin kernel fiber, rye bran, whole grain rye, or a mixed high-fiber diet showed satiety-enhancing effects in multiple studies. 1 . Appropriate protein levels in the diet can improve growth performance, bone quality, and testosterone levels. 4 .

Risks Summary

Most fibers did not reduce appetite or energy intake in short-term study designs. 1 . Transglutaminase treatment may suppress initial intestinal digestion. 3 .

Comparison Between Studies

Similarities

Multiple studies have shown that fiber intake is associated with weight loss. 1 . Also, protein levels have been shown to affect growth performance, bone quality, and testosterone levels. 4 .

Differences

The effects of fiber on satiety and energy intake are not consistent across studies. 1 . The effects of transglutaminase treatment vary depending on the type of protein. 3 . The effects of low-fat versus low-carbohydrate diets on fiber intake are not conclusive. 2 .

Consistency and Contradictions of Results

The results regarding the association between fiber intake and weight loss are consistent, 1 , but the results regarding the effects on satiety and energy intake are contradictory. 1 . The results regarding the effects of protein levels on growth performance, bone quality, and testosterone levels are also consistent. 4 .

Real-Life Application and Precautions

If you are looking to lose weight, consider increasing your intake of foods rich in fiber. 1 . However, keep in mind that not all fibers increase satiety or reduce energy intake. 1 . To improve growth performance, bone quality, and testosterone levels, ensuring adequate protein levels in your diet is essential. 4 .

Limitations of Current Research

The effects of fiber on satiety and energy intake are not consistent across studies. 1 . Therefore, the types and doses of fiber that effectively reduce appetite and energy intake are still unclear. 1 . Further research is needed on the effects of transglutaminase treatment. 3 .

Directions for Future Research

More research is needed to clarify how different types and amounts of fiber affect satiety and energy intake. 1 . The effects of transglutaminase treatment should be investigated with different proteins. 3 . Long-term studies are needed to investigate whether low-fat or low-carbohydrate diets have a greater impact on fiber intake. 2 .

Conclusion

Fiber intake has been shown to be associated with weight loss. 1 . However, further research is needed regarding its effects on satiety and energy intake. 1 . Adequate protein levels in the diet can contribute to improved growth performance, bone quality, and testosterone levels. 4 . To maintain a healthy diet, consuming fiber-rich foods and maintaining appropriate protein levels are essential. 1 4 .

Treatment List

• Dietary fiber

• Transglutaminase treatment

• Low-fat diet

• Low-carbohydrate diet

• High protein diet

• β-glucan

• Lupin kernel fiber

• Rye bran

• Whole grain rye