Lowest calorie protein sources
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Low-Calorie Protein Sources: An Overview
Introduction to Low-Calorie Protein Sources
When aiming for weight loss or maintaining a healthy weight, selecting low-calorie protein sources is crucial. Proteins not only help in muscle maintenance but also play a significant role in satiety, which can aid in reducing overall calorie intake. This article synthesizes findings from various studies to highlight the most effective low-calorie protein sources.
Whey Protein: A Superior Low-Calorie Option
Whey protein has been shown to be highly effective in very-low-calorie ketogenic diets (VLCKDs). In a study comparing whey, vegetable, and animal proteins, whey protein led to significant weight loss and improved metabolic parameters. Additionally, it was more effective in maintaining muscle performance compared to other protein sources1. This makes whey protein an excellent choice for those looking to lose weight while preserving muscle mass.
Soy Protein: Effective and Heart-Healthy
Soy protein is another low-calorie protein source that has demonstrated significant benefits. A study comparing a soy-based low-calorie diet to a traditional low-calorie diet found that the soy-based diet led to greater reductions in body fat percentage and improved lipid profiles, including lower total and LDL cholesterol levels5. These findings suggest that soy protein not only aids in weight loss but also offers cardiovascular benefits.
High-Protein Diets for Weight Maintenance
High-protein diets have been shown to be effective in preventing weight regain after initial weight loss. A large European study found that diets with a modest increase in protein content led to better weight maintenance and higher study completion rates compared to low-protein diets4. This indicates that incorporating higher protein intake can be beneficial for long-term weight management.
Protein Needs During Caloric Restriction
For resistance-trained athletes undergoing caloric restriction, higher protein intake is essential. A systematic review recommended protein intakes of 2.3-3.1g/kg of fat-free mass to preserve muscle mass during periods of energy restriction3. This highlights the importance of adequate protein consumption to prevent muscle loss while dieting.
Very-Low-Calorie Diets: Safety and Efficacy
Very-low-calorie diets (VLCDs) that include high-quality protein sources are effective for significant weight loss. These diets, when medically supervised, have been shown to be safe and can lead to average weight losses of 20 kg in 12 weeks6. However, the choice of protein source is crucial, as it can impact nitrogen balance and overall health outcomes7.
Conclusion
Selecting the right low-calorie protein sources is vital for effective weight loss and maintenance. Whey and soy proteins stand out as superior options due to their efficacy in promoting weight loss, preserving muscle mass, and improving metabolic health. High-protein diets are also beneficial for long-term weight maintenance and are particularly important for athletes and individuals undergoing caloric restriction. When considering very-low-calorie diets, it is essential to choose high-quality protein sources and ensure medical supervision to achieve the best outcomes.
Sources and full results
Most relevant research papers on this topic
Very-Low-Calorie Ketogenic Diets with Whey, Vegetable or Animal Protein in Patients with Obesity: A Randomized Pilot Study.
VLCKDs lead to significant weight loss and improved metabolic parameters, with whey or vegetable protein-based diets being safer and promoting a healthier gut microbiota composition than animal protein-based diets.
RCT
Very Rigorous Journal
Highly CitedTHE LOW PROTEIN DIET
A low protein diet should be individualized for each individual, focusing on whole grains, fruits, vegetables, and low-fat dairy products.
A systematic review of dietary protein during caloric restriction in resistance trained lean athletes: a case for higher intakes.
Energy-restricted resistance-trained athletes need 2.3-3.1g/kg of protein to maintain leanness and maintain muscle mass during caloric restriction.
Systematic ReviewHighly CitedDiets with high or low protein content and glycemic index for weight-loss maintenance.
A modest increase in protein content and a modest reduction in glycemic index improve study completion and weight loss maintenance in overweight adults.
RCTHighly CitedApplied nutritional investigation Effectiveness of a soy-based compared with a traditional low-calorie diet on weight loss and lipid levels in overweight adults
Soy-based low-calorie diets significantly lower cholesterol and body fat percentage, providing health benefits in reducing weight and blood lipids compared to traditional low-calorie diets.
RCTHighly CitedVery low calorie diets: their efficacy, safety, and future.
Very low calorie diets for treating obesity are effective and safe when limited to 3 months under careful medical supervision, but maintaining weight loss remains a challenge.
Highly CitedMetabolic effects of very low calorie weight reduction diets.
Very low calorie weight reduction diets require higher protein intake to maintain nitrogen balance, but peripheral amino acid metabolism may be affected.
RCTHighly CitedThe effect of a low-calorie, high-protein diet on psychometric variables in obese individuals: a Randomized Clinical Trial
A low-calorie, high-protein diet can significantly improve psychometric variables in obese individuals, including depression, stress, and anxiety.
RCTA comparison of two very-low-calorie diets: protein-sparing-modified fast versus protein-formula-liquid diet.
A protein-sparing-modified fast (PSMF) is more effective in reducing hunger and preoccupation with eating than a protein-formula-liquid diet for moderately overweight individuals.
RCT