According to American Journal of Clinical Nutrition, dietary intake of 132 g per day of legume rich diet over a period of at least three weeks has a potential of significant weight loss of 0.34 kg i.e., 0.75 pounds. A meta-analysis concluding results from 21 different researches for checking the clinical effectiveness of legume rich interventions in weight reduction was published earlier this month. The work was funded by Canadian Institutes of Health Research’s Knowledge Synthesis Grant.
The effects of beans, lentils, chickpeas, and dry peas consumption on different anthropometric measures of weight loss including body weight, waist circumference and body fat were evaluated by conducting a review of the randomized controlled trials, including a total of 940 adult men and women.
Lead author Dr Russell de Souza along with colleagues searched for the controlled trials that compared the effects of interventions containing pulses rich diets with those without dietary pulse intake, by using different databases including MEDLINE, Embase, CINAHL, and the Cochrane Library.
The research was established on the previous work by St Michael Hospital’s Clinical Nutrition and Risk Factor Modification Center, stating that a daily serving of pulses makes people feel fuller than if they ate a control diet, and that eating pulses can significantly reduce “bad cholesterol”.
Findings of the study, suggested the presence of a positive correlation between high dietary pulses intake and weight-loss. The researchers noted that pulses have a low glycemic index and are broken down slowly in the body preventing excessive eating.
“Despite their known health benefits, only 13 percent of Canadians eat pulses on any given day and most do not eat the full serving,” said Dr Russell, a researcher at St Michael’s Hospital, Toronto, in a press release.
The researcher focused upon the usefulness of the high protein diet by saying that 90% of weight loss interventions fail due to the hunger and food cravings. While focusing on the satiety inducing ability of legumes, he added, “So there is room for most of us to incorporate dietary pulses in our diet and realize potential weight management benefits. Pulses increased the feeling of fullness by 31 percent which may indeed result in less food intake.” He advised swapping legumes for other sources of proteins by saying, “In another study we did, we found they may help with appetite control — eating 100 calories worth of pulses at a meal will make you feel about one-third more full than 100 calories from another food.”
Two effective tools like Heyland Methodologic Quality Score and Cochrane Risk of Bias tool were used for assessing the quality of the study and eliminating risk of biasness respectively. The data from all the studies was combined by the help of inverse-variance random-effects models. Moreover, results of six studies showed reduction in body fat percentage by switching to pulse rich diet.
The epidemic of obesity is increasing at a very fast pace worldwide. Keeping this issue under consideration the United Nations and the Food and Agriculture Organization labeled 2016 as ‘the International Year of Pulses’, with an aim of increasing awareness of plant based foods. Increased ingestion of pulse rich diet can prove to be a beneficial step.
Dr de Souza insisted upon adding the pulses in diets and concluded the research work by saying, “Though the weight loss was small, our findings suggest that simply including pulses in your diet may help you lose weight, and we think more importantly, prevent you from gaining it back after you lose it.” He believed that the scientific evidences were not enough for characterizing legume rich diets as a sustainable weight loss approach.
Since the study was carried out in Canada first, the author called it an additional bonus to eat locally available leguminous crops. “So eating more pulses means eating local, being more sustainable and receiving many health benefits,” he said.
The importance of including whole grains to the food regime was also strengthened by the latest version of ‘Eatwell Guide’, proposed by PHE. Lentils, chickpeas, baked beans, kidney beans and butter beans were suggested as good alternatives to meat because they are naturally very low in fat and high in fiber, protein, vitamins and minerals.
Legumes Reduce Central Obesity
Another study published in the Journal of Research in Medical Sciences by Alizadeh et al revealed that eating a legumes-rich diet for six weeks reduced anthropometric measures associated with central obesity in 84 healthy premenopausal women. The waist, hip, triceps, biceps, subscapular and suprailiac skin fold thicknesses reduced considerably.
The weight reducing effect of legumes was also validated by a research on 30 obese subjects intervened with a legume enriched diet for eight weeks, four days/week who lost weight due the presence of L-Arginine and selenium present in hypocaloric leguminous diet.
Legumes Improves Metabolism Of Overweight Persons
According to another study, positive effects of legume-based diet on lowering of inflammation causing markers and improving metabolic features in overweight obese subjects were seen. Eight week-long trial consisting of legumes consumed in four servings per week resulted in reduction of CRP and C3, the proinflammatory markers, improvement in lipid profile and BP in overweight-obese subjects.
Protein Diets Should Be Taken With Care
Furthermore, a negative effect of protein rich diet was confirmed by a prospective study conducted by the researchers from Department of Medicine in collaboration with University of Vermont, Burlington VT, USA. Legume consumption of protein rich food resulted in increasing the values of C-reactive protein (CRP), leading to increased risk for coronary heart disease in older men and women.
The research work covering the anti-obesity effects of black soy peptides provided evidences of decreased appetite and diet-induced body weight gain through leptin-like STAT3 phosphorylation and AMPK activation along with daily exercising.
The research work conducted by Canadian scientist was a meta-analysis of 21 different researches which supported the fact that legume rich food aids in effective weight loss due to high protein levels from plant sources like beans, lentils, chickpeas and dry peas. The mechanism of action of such high protein diets work by increasing the secretions of satiety inducing hormones GIP, GLP-1 and reduced secretions of appetite stimulating hormone ghrelin. The foods high in protein increase the thermic effect in the body due to which more calories are burned. Thus, metabolic activities are boosted and result is weight loss.